muramidase and Bacterial-Infections

In 2013, Dr. Lora Hooper and colleagues described the induction of antibacterial macroautophagy/autophagy in intestinal epithelial cells as a cytoprotective host defense mechanism against invading Salmonella enterica serovar Typhimurium (S. Typhimurium). Canonical autophagy functions in a primarily degradative capacity to safeguard cells and ensure survival during stress conditions, including pathogen infection. In contrast, secretory autophagy has emerged as an alternative nondegradative mechanism for cellular trafficking and unconventional protein secretion. More recently, a study by Bel et al. from Dr. Hooper's lab describes how intestinal Paneth cells exploit the endoplasmic reticulum (ER) stress response to release antibacterial lysozyme through secretory autophagy in response to S. Typhimurium infection.

Topics: Animals; Autophagy; Bacterial Infections; Humans; Intestines; Muramidase; Salmonella Infections; Salmonella typhimurium

Bacterial infections remain a major public health concern. However, broad-spectrum antibiotics largely target redundant mechanisms of bacterial survival and lead to gained resistance owing to microbial evolution. New methods are needed to attack bacterial infections, and we have only begun to seek out nature's vast arsenal of antimicrobial weapons. Enzymes offer one such weapon, and their diversity has been exploited to kill bacteria selectively through unique targets, particularly in bacterial cell walls, as well as nonselectively through generation of bactericidal molecules. In both approaches, microbial resistance has largely been absent, which bodes well for its potential use in human therapeutics. Furthermore, enzyme stabilization through conjugation to nanoscale materials and incorporation into polymeric composites enable their use on surfaces to endow them with antimicrobial properties. Here, we highlight the use of enzymes as antimicrobial agents, including applications that may prove effective in new therapeutics and through control of key societal infrastructures.

Topics: Animals; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Bacteriophages; Biocatalysis; Drug Discovery; Drug Resistance, Microbial; Enzymes; Humans; Hydrolases; Laccase; Muramidase; Peptide Hydrolases; Peroxidases

Lysozyme is a cornerstone of innate immunity. The canonical mechanism for bacterial killing by lysozyme occurs through the hydrolysis of cell wall peptidoglycan (PG). Conventional type (c-type) lysozymes are also highly cationic and can kill certain bacteria independently of PG hydrolytic activity. Reflecting the ongoing arms race between host and invading microorganisms, both gram-positive and gram-negative bacteria have evolved mechanisms to thwart killing by lysozyme. In addition to its direct antimicrobial role, more recent evidence has shown that lysozyme modulates the host immune response to infection. The degradation and lysis of bacteria by lysozyme enhance the release of bacterial products, including PG, that activate pattern recognition receptors in host cells. Yet paradoxically, lysozyme is important for the resolution of inflammation at mucosal sites. This review will highlight recent advances in our understanding of the diverse mechanisms that bacteria use to protect themselves against lysozyme, the intriguing immunomodulatory function of lysozyme, and the relationship between these features in the context of infection.

Topics: Animals; Anti-Infective Agents; Bacteria; Bacterial Infections; Humans; Immune System Phenomena; Muramidase; Peptidoglycan

As the interactions of phage with mammalian innate and adaptive immune systems are better delineated and with our ability to recognize and eliminate toxins and other potentially harmful phage gene products, the potential of phage therapies is now being realized. Early efforts to use phage therapeutically were hampered by inadequate phage purification and limited knowledge of phage-bacterial and phage-human relations. However, although use of phage as an antibacterial therapy in countries that require controlled clinical studies has been hampered by the high costs of patient trials, their use as vaccines and the use of phage components such as lysolytic enzymes or lysozymes has progressed to the point of commercial applications. Recent studies concerning the intimate associations between mammalian hosts and bacterial and phage microbiomes should hasten this progress.

Topics: Animals; Anti-Bacterial Agents; Bacterial Infections; Bacteriophages; Disease Models, Animal; Humans; Muramidase; Vaccines

Bacterial pathogens that colonize mucosal surfaces have acquired resistance to antimicrobials that are abundant at these sites. One of the main antimicrobials present on mucosal surfaces is lysozyme, a muramidase that hydrolyzes the peptidoglycan backbone of bacteria. Cleavage of the peptidoglycan backbone leads to bacterial cell death and lysis, which releases bacterial fragments, including peptidoglycan, at the site of infection. Peptidoglycan fragments can be recognized by host receptors and initiate an immune response that will aid in clearing infection. Many mucosal pathogens modify the peptidoglycan residues surrounding the cleavage site for lysozyme to avoid peptidoglycan degradation and the release of these proinflammatory fragments. This review will focus specifically on peptidoglycan modifications, their role in lysozyme resistance, and downstream effects on the host immune response to infection.

Topics: Animals; Anti-Infective Agents; Bacteria; Bacterial Infections; Muramidase; Peptidoglycan

This paper presents some processes of the antibacterial effect of serum, which mainly results from the activities of complement (C) and lysozyme (muramidase, LZ). The C system consists ofa group of serum proteins and tissue fluids which are activated in a particular order. Complement,operating together with lysozyme, constitutes the main protection from microorganisms entering the body. Pathogenic microorganisms are able to avoid natural protective mechanisms by, among others, molecular mimicry, binding complement control proteins, or secreting proteolytic enzymes.The effectiveness of the cytolytic action of C proteins and LZ also depends on the surface structures of the microorganisms. Imbalance between the activation and deactivation of inflammatory reactions in the presence of pathogens can lead to various pathological states, such as autoimmunological diseases.

Topics: Animals; Bacterial Infections; Blood Bactericidal Activity; Complement Activation; Complement System Proteins; Host-Pathogen Interactions; Humans; Molecular Mimicry; Muramidase; Serum

Peptidoglycan is the major structural component of bacterial cell walls. In this era of increasingly antibiotic resistant pathogens, peptidoglycan hydrolases that degrade this important cell wall structure have emerged as a potential novel source of new antimicrobials. Included in this class are bacteriocins (lysostaphin), lysozyme, and bacteriophage endolysins. Bacteriophage are viruses that infect and utilize bacteria as their host. They can reside in the bacterial genome as a prophage, or enter the lytic phase, take over the bacterial gene expression machinery, synthesize new phage particles, lyse the host, and release up to hundreds of phage progeny. Lysis occurs during the late phase of the lytic cycle when the phage endolysin and a holin molecule are produced. The holin creates holes in the cells lipid bilayer allowing the phage endolysin (peptidoglycan hydrolase) to escape and degrade the structural portion of the cell wall. These (and other phage encoded proteins) have been shown to inhibit bacterial growth. The ability to inhibit growth or kill bacteria make both the bacteriophage and their gene products a rich source of potential antimicrobials. This review summarizes the recent resurgence of these potential antimicrobials as both diagnostic and therapeutic agents and identifies recent patents that describe these technologies.

Topics: Anti-Infective Agents; Bacteria; Bacterial Infections; Bacteriophages; Cell Wall; Drug Resistance, Bacterial; Endopeptidases; Humans; Muramidase; Patents as Topic; Peptidoglycan; Viral Proteins

The mucosal surface of the gastrointestinal tract represents a major entry point and ecological niche for many microbes. It forms an important immune barrier, absorbing nutrients, whilst preventing invasion by organisms. Of the extra-ordinarily diverse species that comprise the microbial world, relatively few organisms are able to succeed in breaching this barrier in an otherwise healthy host. The production and secretion of antimicrobial peptides (AMPs) from surface epithelia and circulating immune cells are likely to play a key role in host protection and homeostasis. A number of these peptides are constitutively produced providing resident protection, whereas others are induced during infection and inflammation. In addition to directly eradicating microorganisms, it is becoming increasingly apparent that AMPs are multi-functional with diverse immuno-modulatory properties. This review focuses on three families of AMPs, defensins, cathelicidins, and lysozyme, and discusses their role in mucosal defence.

Topics: Antimicrobial Cationic Peptides; Bacterial Infections; Cathelicidins; Defensins; Gastrointestinal Tract; Humans; Immunity, Innate; Muramidase

Topics: Adult; Age Factors; Aged; Antimicrobial Cationic Peptides; Bacterial Infections; Female; Humans; Immunoglobulins; Lactoferrin; Male; Middle Aged; Muramidase; Phospholipases A; Sensitivity and Specificity; Tears

Many different genetic strategies have been proposed to engineer plant resistance to bacterial diseases, including producing antibacterial proteins of non-plant origin, inhibiting bacterial pathogenicity or virulence factors, enhancing natural plant defenses and artificially inducing programmed cell death at the site of infection. These are based on our knowledge of the mechanisms of action of antibacterial compounds and of the successive steps in plant-bacterial interactions. This article presents the different approaches and demonstrates that, even though several of these ideas have already been applied, no commercial applications have yet been achieved.

Topics: Animals; Anti-Bacterial Agents; Apoptosis; Bacteria; Bacterial Infections; Genes, Plant; Genetic Engineering; Insecta; Muramidase; Peptides; Plant Diseases; Plants, Edible; Plants, Genetically Modified

In the first section the assay methods of lysozyme are reviewed. It is pointed out that there is no method using the hydrolysis of NAM- > beta-1, 4-glycoside bond- > NAG, So to clarify relation between methods will lead to discovery of new isozymes. In the second chapter serum or urinary lysozyme levels are discussed in the states of diseases. The high levels are induced by cell proliferation which are producing lysozyme. The type of cells and their nature may infer different lysozymes that has no clear evidences yet. In the third part lysozyme is reviewed as protein and product of gene. In the final, enzyme kinetics are the subject of investigation, and further studies may by chance conduct us to find out new isozymes of lysozyme in near future.

Topics: Bacterial Infections; Clinical Enzyme Tests; Humans; Isoenzymes; Leukemia; Muramidase

In the mammary gland of cattle there is a complex defense system of non-specific and specific reactions available preventing the invasion of pathogenic bacteria. Most infections occur via the teat canal, so teat canal keratin (SKK) is of particular importance in non-specific defense of the gland. The SKK serves as a physical barrier, and bacteriostatic and/or bactericidal effects of SKK lipids and proteins against certain mastitis bacteria could be demonstrated. By increasing the concentrations of lactoferrin and lysozyme in milk a reduction of mastitis frequencies could be observed. However, those high concentrations in the proteins occur only during the dry period of the cow. An improvement of the mastitis situation would also appear possible by increasing phagocytosis. The numerous trials intended to reduce mastitis by improving specific protection showed no significant success. Therefore, the most successful and cheapest means to achieve udder health remains the strict and consistent hygiene of housing, animals and mammary glands.

Topics: Animals; Bacterial Infections; Cattle; Female; Keratins; Lactoferrin; Lipids; Mammary Glands, Animal; Mastitis, Bovine; Milk; Milk Proteins; Muramidase; Phagocytosis

Extracellular killing provides an attractive hypothesis to explain the rapid alveolar killing of inhaled bacterial pathogens in the absence of conventional opsonins for phagocytosis. Some evidence of extracellular killing of inhaled pneumococci has been obtained using histologic studies and bronchoalveolar lavage. Although studies of the antimicrobial activity of lung lavage fluid in vitro have given variable results, a variety of antimicrobial factors have been detected in lung lavage fluids. Studies of lysozyme, peptides, iron binding proteins, free fatty acids and other factors that are found free in lung lavage fluid indicate that some of these factors could be a part of extracellular pulmonary host defenses. However, their precise role is not known. A survey of mechanisms of extracellular killing shows that granulocytes, monocytes, macrophages, and T lymphocytes all have the capacity to kill extracellularly in vitro in some circumstances. It remains to be determined which of these diverse mechanisms operate within the lung and how they function in relationship to other host defenses.

Topics: Animals; Bacterial Infections; Bronchoalveolar Lavage Fluid; Fatty Acids, Nonesterified; Humans; Lactoferrin; Leukocytes; Lung; Muramidase; Pancreatic Elastase; Peptides; Phagocytosis; Pulmonary Alveoli; Pulmonary Surfactants; Transferrin

Bacterial infection may be responsible for mild self-limiting disease, chronic disease or acute and devasting ocular destruction. This paper and those that follow deal with some of the clinical forms of disease which are encountered, the bacteria responsible, the mechanism of invasion and the natural defences and clinical management, including selection and delivery of antibiotics.

Topics: Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Bacterial Infections; Bacteriolysis; Blood Proteins; Ceruloplasmin; Complement Activation; Eye Diseases; Humans; Immunoglobulin A; Lactoferrin; Muramidase; Proteins; Tears

Topics: Administration, Oral; Animals; Bacterial Infections; Bacterial Vaccines; Gastric Acid; Humans; Immunity, Cellular; Immunity, Innate; Immunization, Passive; Immunoglobulin A; Interferons; Intestinal Diseases; Intestinal Diseases, Parasitic; Intestinal Mucosa; Intestines; Lactoferrin; Muramidase; Vaccination; Vaccines; Vaccines, Attenuated

The portal of entry for most pathogens is at the mucosal surface, and mucosal defences afford the host the earliest opportunity to ward off infection. The vagina is exposed to considerable trauma, and harbours a complex microflora, but only a small number of microorganisms are associated with disease. It seems likely that mucosal defenses are important in this process. Mucosal secretions contain mucus, lysozyme, lactoferrin, zinc, fibronectin, and complement, all of which afford non-specific protection. In addition, secretory immunoglobulin A (IgA) concentration in these secretions increases in response to specific pathogens. Blood leukocytes migrate onto mucosal surfaces during infection with some microorganisms, and the interaction between phagocytic cells and genital pathogens has been the focus of intense investigation. Improved understanding of mucosal defences is crucial for prevention of infection.

Topics: Aging; Antibody Formation; Bacterial Infections; Female; Fibronectins; Humans; Iron; Mucous Membrane; Muramidase; Phagocytosis; Pregnancy; Pregnancy Complications, Infectious; Vagina; Vaginitis; Zinc

Topics: Animals; Bacteria; Bacterial Infections; Blood Bactericidal Activity; Cell Membrane; Complement Activation; Complement System Proteins; Guinea Pigs; Humans; Hydrogen-Ion Concentration; Immunity; Immunoglobulins; Lipopolysaccharides; Muramidase; Plasmids; Polysaccharides, Bacterial; Rabbits; Rats

Topics: Bacterial Infections; C-Reactive Protein; Complement System Proteins; Female; Fetomaternal Transfusion; Humans; Immunity, Cellular; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature; Leukocytes; Maternal-Fetal Exchange; Muramidase; Phagocytosis; Pregnancy

Topics: Adolescent; Adult; Age Factors; Aged; Bacteria; Bacterial Infections; Cells, Cultured; Female; Gingivitis; Humans; Male; Mastication; Middle Aged; Muramidase; Periodontal Diseases; Periodontitis; Phagocytosis; Polysaccharides, Bacterial; Saliva

Topics: Animals; Animals, Newborn; Bacterial Infections; Blood Bactericidal Activity; Body Temperature; Chick Embryo; Chickens; Egg Proteins; Egg Shell; Female; Infections; Intestines; Muramidase; Mycoses; Ovalbumin; Phagocytosis; Skin; Transferrin; Virus Diseases; Vitelline Membrane

Topics: Animals; Bacteria; Bacterial Infections; Central Nervous System Diseases; Circadian Rhythm; Diagnosis, Differential; Hepatitis A; Leukemia; Lysosomes; Muramidase; Periodicity; Rabbits; Rats; Virus Diseases

Topics: Bacterial Infections; Burns; Chediak-Higashi Syndrome; D-Amino-Acid Oxidase; Glutathione; Glutathione Reductase; Hexoses; Humans; Infant, Newborn; Leukocytes; Lipids; Muramidase; NAD; NADP; Neutrophils; Oxidation-Reduction; Peroxidases; Phagocyte Bactericidal Dysfunction; Proteins

Topics: Animals; Autolysis; Bacterial Infections; Cephalosporins; Clostridium; Crystallography; Drug Stability; Escherichia coli; Guinea Pigs; History, 20th Century; Humans; Mice; Microbial Sensitivity Tests; Micrococcus; Muramidase; Penicillanic Acid; Penicillins; Penicillium; Rabbits; Salmonella; Streptococcal Infections

Matrix metalloproteinases (MMPs) are crucial for tissue remodeling and immune responses in insects, yet it remains unclear how MMPs affect the various immune processes against pathogenic infections and whether the responses vary among insects. In this study, we used the lepidopteran pest Ostrinia furnacalis larvae to address these questions by examining the changes of immune-related gene expression and antimicrobial activity after the knockdown of MMP14 and bacterial infections. We identified MMP14 in O. furnacalis using the rapid amplification of complementary DNA ends (RACE), and found that it was conserved and belonged to the MMP1 subfamily. Our functional investigations revealed that MMP14 is an infection-responsive gene, and its knockdown reduces phenoloxidase (PO) activity and Cecropin expression, while the expressions of Lysozyme, Attacin, Gloverin, and Moricin are enhanced after MMP14 knockdown. Further PO and lysozyme activity determinations showed consistent results with gene expression of these immune-related genes. Finally, the knockdown of MMP14 decreased larvae survival to bacterial infections. Taken together, our data indicate that MMP14 selectively regulates the immune responses, and is required to defend against bacterial infections in O. furnacalis larvae. Conserved MMPs may serve as a potential target for pest control using a combination of double-stranded RNA and bacterial infection.

Topics: Animals; Bacterial Infections; Immunity; Larva; Matrix Metalloproteinase 14; Moths; Muramidase

Sustainable methods that increase farmed fish yield while controlling infections are required to prevent economic losses in aquaculture farms. In this study, we evaluated the effects of betaine-supplemented (0%, 0.1%, 0.5%, and 1.0%) feed on the growth and immunity of the olive flounder Paralichthys olivaceus. Feed conversion ratios, post-infection cumulative mortality rates and innate immune responses were monitored. Weight gain was significantly higher with 0.5% and 1.0% than with 0% and 0.1% betaine-supplemented feed. Lysozyme activity was highest with 1.0% betaine. Respiratory burst activity was highest with 0.5% and 1.0% betaine. Serum bactericidal activity against Edwardsiella tarda was highest with 1.0% betaine (40% increase in survival rates compared with those in the control). Furthermore, serum virucidal activity against the viral haemorrhagic septicaemia virus (VHSV) was higher with 1.0% betaine than with other concentrations. With 0.5% and 1.0% betaine, the survival rates against VHSV were higher than those in the control until day 11, after which they declined. Our study suggests that betaine is a promising agent for promoting the growth of and enhancing immunity against E. tarda in olive flounders. Our findings may further contribute to developing necessary alternatives to conventional antibiotics in fish farming.

Topics: Animals; Anti-Bacterial Agents; Bacterial Infections; Betaine; Edwardsiella tarda; Enterobacteriaceae Infections; Fish Diseases; Flounder; Immunity, Innate; Muramidase

In this study, we isolated and characterized natural antibodies found in serum samples from Bester sturgeon (Huso huso × Acipenser ruthenus). Natural antibodies specifically detected hen egg lysozyme (HEL), keyhole limpet hemocyanin (KLH), and several species of pathogenic bacteria. Interestingly, we detected no antibodies with similar specificity in serum samples from rainbow trout (Oncorhynchus mykiss) or from Japanese flounder (Paralichthys olivaceus). Binding capacity of the sturgeon natural serum antibodies increased slightly at 7 months compared to 3 months after hatching. Antigen-specific antibodies against KLH, Aeromonas hydrophila and Streptococcus iniae were affinity-fractionated from naive sera of Bester sturgeon; specific detection of the corresponding antigens was observed. We conclude that Bester sturgeon are capable of generating unique natural antibodies including those that are pathogen-specific.

Topics: Aeromonas hydrophila; Animals; Antibodies; Bacterial Infections; Biological Evolution; Chromatography, Affinity; Epitopes; Fish Proteins; Fishes; Flounder; Gene Expression Regulation; Hemocyanins; Immunity, Humoral; Muramidase; Oncorhynchus mykiss; Phylogeny; Reproduction; Streptococcus iniae

Topics: Animals; Aquaculture; Bacterial Infections; Bacteriophages; Muramidase; Penaeidae; Phage Therapy; Salinity; Seawater; Vibrio

Lactic acid bacteria (LAB) play an important role in pig health and performance that arises from their beneficial impacts on the balance of gastrointestinal microbes, ability to fight enteric pathogens, and capacity to support the immune system. The aim of this study was to evaluate the functional and safety aspects of five previously isolated autochthonous LAB strains, (Lactobacillus plantarum 22F, 25F and 31F, Pediococcus acidilactici 72N and Pediococcus pentosaceus 77F) from pig faeces as potential probiotics for a pig feed supplement. The functional and safety properties of the strains were assessed by in vitro tests. The functional properties tested were their abilities in tolerating low pH values under simulated gastric conditions, their cell surface properties (hydrophobicity, auto- and co-aggregation), antibacterial activity against the common enteric pathogenic bacteria in pigs (such as pathogenic Escherichia coli, Salmonella Choleraesuis and Streptococcus suis), and diacetyl production. The safety of the strains was analyzed based on the absent of haemolysis on blood and bile salt hydrolase activity. Although all strains demonstrated diacetyl production, good survivability and antibacterial activities, L. plantarum 22F and 25F showed the best performance with the strongest antibacterial actions against the indicator pathogens. Of the strains, only P. pentosaceus 77F exhibited haemolysis or bile salt hydrolase activity. Furthermore, a principal component analysis revealed that L. plantarum 22F possessed superior functional and safety aspects compared to the other four autochthonous strains and to reference strains L. plantarum JCM 1149 and P. acidilactici DSM 20284. Further in vivo studies using oral administration of the strains are justified to assess their effectiveness as feed supplements for pigs.

Topics: Amidohydrolases; Animals; Anti-Bacterial Agents; Bacterial Infections; Bile Acids and Salts; Enterobacteriaceae; Feces; Gastric Juice; Gastrointestinal Microbiome; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Lactobacillales; Lactobacillus plantarum; Muramidase; Pediococcus acidilactici; Pediococcus pentosaceus; Phenol; Probiotics; Swine; Thailand

β-glucan has been shown to increase non-specific immunity and resistance against infections or pathogenic bacteria in several fish species, but information regarding its trans-generational immune-enhancing effects is still rather limited. Lysozyme is a maternal immune factor playing an important role in the developing embryos of zebrafish. Here we clearly showe that β-glucan enhanced the level of C-type lysozyme in eggs of zebrafish, and the embryos derived from β-glucan-treated zebrafish were more resistant to bacterial challenge than control embryos. Moreover, the transferred lysozyme was apparently linked with the antimicrobial defense of early embryos. In addition, we also showed that β-glucan induced a significant increase in the synthesis of C-type lysozyme in previtellogenetic oocytes. Therefore, we show for the first time that β-glucan can enhance the lysozyme level in offspring via both inducing the transfer of the molecule from mothers to eggs and stimulating its endogenous production in oocytes.

Topics: Animals; Anti-Bacterial Agents; Bacterial Infections; beta-Glucans; Cells, Cultured; Diet; Eggs; Female; Fish Diseases; Gene Expression Regulation, Developmental; Immunity, Innate; Muramidase; Oocytes; Up-Regulation; Zebrafish; Zebrafish Proteins

Black rockfish (Sebastes schlegelii), an important aquaculture species in Korea, has been affected by bacterial diseases leading to a drastic decline in production. Goose-type lysozyme (LysG) is a key enzyme of the innate immune system to eradicate bacterial infections. In this study, two isoforms of LysG from black rockfish, designated as RfLysG1 and RfLysG2, have been identified and characterized at the molecular, transcriptional, and functional levels. The deduced amino acid sequences had the LysG family characteristics and exhibited conserved properties, including active residues and domains. The cDNA sequences of RfLysG1 and RfLysG2 were 1514 bp and 900 bp in length, respectively. The 567-bp open reading frame (ORF) of RfLysG1 encoded a protein of 188 amino acids with molecular mass 20.11 kDa, and the 600-bp ORF of RfLysG2 encoded a polypeptide with 199 amino acids and molecular mass of 22.19 kDa. Homology studies indicated that RfLysG1 showed the highest identity (84.6%) with LysG-B of Oplegnathus fasciatus, while RfLysG2 showed the highest identity (74.4%) with LysG of Siniperca chuatsi. Both sequences possessed a soluble lytic trans-glycosylase domain. Both lacked signal peptide and they were not identified as proteins secreted by non-classical pathway by the SecretomeP server. Transcriptional analysis of the two genes showed constitutive expression, where both genes were highly expressed in blood under normal physiological conditions. In response to the immune challenges lipopolysaccharide (LPS), Streptococcus iniae, and poly I:C injection, the expression of RfLysG1 and RfLysG2 was significantly upregulated in blood and spleen tissues in a time-dependent manner. Turbidimetric assays indicated that both recombinant proteins tagged with maltose-binding protein (MBP) were reactive against several Gram-positive and Gram-negative bacteria, but MBP was inactive. Optimum temperatures for the recombinant RfLysG1 and RfLysG2 were 40 °C and 50 °C, respectively, and both were highly active at pH 3.0. The results provide evidence for the vital immunological role and bacteriolytic potential of RfLysG1 and RfLysG2.

Topics: Amino Acid Sequence; Animals; Bacterial Infections; Fish Diseases; Fish Proteins; Fishes; Gene Expression Regulation; Gram-Negative Bacteria; Gram-Positive Bacteria; Immunity, Innate; Muramidase; Phylogeny; Sequence Alignment

Topics: Autophagy; Bacterial Infections; Humans; Immunity, Innate; Intestines; Muramidase; Paneth Cells

Lysozyme is an important defense molecule of the innate immune system. Known for its bactericidal properties, lysozyme catalyzes the hydrolysis of b-(1,4)-glycosidic bonds between the N-acetyl glucosamine and N-acetyl muramic acid in the peptidoglycan layer of bacterial cell walls. In this study, the complete coding sequence of four g-type lysozymes were identified in Ciona intestinalis. Phylogenetic analysis and modelling supported the hypothesis of a close relationship with the vertebrate g-type lysozymes suggesting that the C. intestinalis g-type lysozyme genes (CiLys-g1, Cilys-g2, CiLys-g3, CiLys-g4) share a common ancestor in the chordate lineage. Protein motif searches indicated that C. intestinalis g-type lysozymes contain a GEWL domain with a GXXQ signature, typical of goose lysozymes. Quantitative Real-Time PCR analysis results showed that transcripts are expressed in various tissues from C. intestinalis. In order to determine the involvement of C. intestinalis g-type lysozymes in immunity, their expression was analyzed in the pharynx, showing that transcripts were significantly up-regulated in response to a challenge with lipopolysaccharide (LPS). These data support the view that CiLys g-type are molecules with potential for immune defense system against bacterial infection.

Topics: Animals; Bacterial Infections; Bacteriolysis; Biological Evolution; Cells, Cultured; Ciona intestinalis; Cloning, Molecular; Evolution, Molecular; Geese; Immunity, Innate; Lipopolysaccharides; Muramidase; Pharynx; Phylogeny; Transcriptome

Healthcare-associated infections (HAIs) are the infections that patients get while receiving medical treatment in a medical facility with bacterial HAIs being the most common. Silver and gold nanoparticles (NPs) have been successfully employed as antibacterial motifs; however, NPs leaching in addition to poor dispersion and overall reproducibility are major hurdles to further product development. In this study, the authors design and fabricate a smart antibacterial mixed-matrix membrane coating comprising colloidal lysozyme-templated gold nanoclusters as nanofillers in poly(ethylene oxide)/poly(butylene terephthalate) amphiphilic polymer matrix. Mesoporous silica nanoparticles-lysozyme functionalized gold nanoclusters disperse homogenously within the polymer matrix with no phase separation and zero NPs leaching. This mixed-matrix coating can successfully sense and inhibit bacterial contamination via a controlled release mechanism that is only triggered by bacteria. The system is coated on a common radiographic dental imaging device (photostimulable phosphor plate) that is prone to oral bacteria contamination. Variation and eventually disappearance of the red fluorescence surface under UV light signals bacterial infection. Kanamycin, an antimicrobial agent, is controllably released to instantly inhibit bacterial growth. Interestingly, the quality of the images obtained with these coated surfaces is the same as uncoated surfaces and thus the safe application of such smart coatings can be expanded to include other medical devices without compromising their utility.

Topics: Bacterial Infections; Coated Materials, Biocompatible; Delayed-Action Preparations; Gold Colloid; Humans; Kanamycin; MCF-7 Cells; Muramidase; Nanoparticles; Silicon Dioxide

The recruitment of neutrophils by endothelial cells during infection has been extensively studied, but little is known about the regulation of neutrophils activity by endothelial cells. To examine the role of microvascular endothelial cells in neutrophil killing, we established a transmigration model using rat intestinal microvascular endothelial cells (RIMVECs) and measured the extracellular and intracellular killing of Escherichia coli, Lactobacillus acidophilus, and Staphylococcus aureus by transendothelial neutrophils. We observed that blood neutrophils engulfed bacteria but did not kill them, and lipopolysaccharide- or hemolysin-injured RIMVECs inhibited the extracellular and intracellular bactericidal activity of transendothelial neutrophils. In comparison, interleukin-1α-induced RIMVECs promoted the extracellular and intracellular killing activity of transendothelial neutrophils and significantly increased MMP-9 concentration and lysozyme activity in transendothelial neutrophils (p < 0.01 and p < 0.001, respectively). Our results demonstrated that activation of endothelial cells enhanced bactericidal activity of transendothelial neutrophils and bacterial toxin damage of endothelial cells led to reduction in bactericidal activity of transendothelial neutrophils. These findings offered new insight into the role of endothelial cells in the bactericidal activity of neutrophils.

Topics: Animals; Bacterial Infections; Cells, Cultured; Cytotoxicity, Immunologic; Endothelial Cells; Gene Expression Regulation; Host-Pathogen Interactions; Interleukin-1alpha; Lipopolysaccharides; Matrix Metalloproteinase 9; Muramidase; Neutrophils; Rats; Rats, Inbred Strains; Transendothelial and Transepithelial Migration

Lysozymes are important defense proteins of the innate immune system and possess high antibacterial activities. In the present study, a full-length c-type lysozyme cDNA (HtLysC) was cloned and characterized from taimen (Hucho taimen, Pallas). The cDNA contains an open reading frame (ORF) of 432 bp encoding 143 amino acid (aa), with 97% identity to LysC of Rainbow trout (Oncorhynchus mykiss). The amino acid sequence possessed a LYZ1 domain (16-140 aa) which contained two conserved residues (Glu 50 and Asp 67), eight conserved cysteine residues and a calcium binding site. RT-PCR analysis showed that HtLysC transcripts were most abundant in liver and less in muscle. The expression of HtLysC was up-regulated in the liver when challenged with Yersinia ruckeri. The recombinant HtLysC (rHtLysC) had lytic activities against Micrococcus lysodeikticus, Aeromonas salmonicida and Y. ruckeri. Enzyme assay showed that the optimal temperature and pH of rHtLysC were 55 °C and 6.0, respectively. Taken together, these results indicated that HtLysC might play an important role in innate immune defense against bacterial pathogens as a functional lysozyme.

Topics: Aeromonas salmonicida; Animals; Anti-Infective Agents; Bacterial Infections; Cloning, Molecular; Fish Proteins; Immunity, Innate; Lectins, C-Type; Liver; Micrococcus; Muramidase; Muscles; Salmonidae; Transcriptome; Yersinia ruckeri

Topics: Animals; Bacteria; Bacterial Infections; Cloning, Molecular; DNA, Complementary; Fish Diseases; Fish Proteins; Flatfishes; Gene Expression; Muramidase; Phylogeny; Recombinant Proteins

Destabilase-lysozyme (mlDL) is an enzyme secreted by the salivary gland cells of medicinal leeches. Destabilase-lysozyme possesses lysozyme and isopeptidase activities. We generated recombinant destabilase-lysozyme isoform 2 in three expression systems, i.e., in the bacteria Escherichia coli, in the yeast Pichia pastoris, and in the human cell line Expi293F. In E. coli, we generated both polypeptide in inclusion bodies that was later undergone to the refolding and soluble protein that had been fused with the chaperone SlyD. The chaperone was later cleaved by a specific TEV-protease. In cultures of the yeast P. pastoris and the human cell line Expi293F, the soluble form of destabilase-lysozyme was accumulated in the culture media. For the generated enzymes, we determined the lysozyme, isopeptidase and fibrinolytic activities and tested their general antimicrobial effects. The comparisons of the enzymes generated in the different expression systems revealed that all of the destabilase-lysozymes obtained in the soluble forms possessed equal levels of lysozyme, isopeptidase and fibrinolytic activities that exceeded several to ten times the levels of the same activities of the destabilase-lysozyme renaturated from the inclusion bodies. A similar pattern of the differences in the levels of the general antimicrobial effects was observed for the destabilase-lysozymes generated in the soluble form and as inclusion bodies.

Topics: Animals; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Cell Line; Cloning, Molecular; Endopeptidases; Escherichia coli; Fibrinolytic Agents; Hirudo medicinalis; Humans; Muramidase; Pichia; Protein Refolding; Recombinant Proteins; Solubility

In this study, we investigated the immune enhancing effects of different adjuvants used in a pentavalent vaccine for turbots. The pentavalent vaccine consisted of inactive bacterial cells from five common pathogenic strains (Vibrio anguillarum, Vibrio scophtalmi, Edwardsiella tarda, Vibrio harveyi and Vibrio alginolyticus) and the adjuvants were astragalus polysaccharides (APS), propolis, and the Freund's complete adjuvant (FCA). Turbots were immunized with the pentavalent vaccine alone or with one of the adjuvants, and the immune efficiency was evaluated by measuring the activities of lysozyme (LSZ) and superoxide dismutase (SOD), and serum antibody titers. Fish were also challenged with the pathogens after immunization and the relative percent survival (RPS) was assessed. Our results showed that APS, propolis, and FCA had significant immune-enhancing effects on turbots as shown by the higher titers of antibodies against the pathogens, increased LSZ and SOD activities, and enhanced RPS after challenge with pathogens. Among the three adjuvants, FCA had the most significant immune synergistic effects with the vaccine, and APS and propolis had lower and similar immune synergies.

Topics: Adjuvants, Immunologic; Animals; Antibodies, Bacterial; Bacterial Infections; Bacterial Vaccines; Enterobacteriaceae; Enterobacteriaceae Infections; Fish Diseases; Flatfishes; Immunity; Immunization; Muramidase; Superoxide Dismutase; Survival Analysis

Lysozyme is a muramidase that inflicts damage on bacterial cell wall by catalyzing the cleavage of the beta-1,4-glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine in peptidoglycan. Lysozymes are classified into several types, one of which is the goose-type (g-type). In this study, we identified and analyzed a g-type lysozyme (SmLysG) from turbot Scophthalmus maximus. The deduced amino acid sequence of SmLysG contains 193 residues and is most closely related to that of the g-type lysozyme of Scophthalmus rhombus (94% overall identity). SmLysG possesses a Goose Egg White Lysozyme (GEWL) domain with conserved residues essential for catalytic activity. Recombinant SmLysG (rSmLysG) purified from yeast exhibits strong lysozyme activity against Micrococcus luteus. Enzyme assays showed that the optimal temperature and pH of rSmLysG are 30°C and pH 7.0, respectively. Substrate spectrum analysis indicated that rSmLysG inhibited the growth of a number of important fish pathogens of both Gram-negative and Gram-positive natures. SmLysG transcription was detected in multiple tissues and was upregulated in kidney and spleen by experimental challenges with lipopolysaccharide and bacterial pathogens that are, respectively, sensitive to and resistant against the lytic effect of rSmLysG. Comparative analysis showed that although bacterial infection also induced the expression of c-type lysozyme, the induction levels were much lower than those of SmLysG. Taken together, these results indicate that SmLysG is a functional g-type lysozyme with a wide working range and is involved in innate immune defense against general bacterial infection.

Topics: Animals; Bacteria; Bacterial Infections; Fish Diseases; Flatfishes; Gene Expression Profiling; Gene Expression Regulation, Enzymologic; Hydrogen-Ion Concentration; Immune System; Molecular Sequence Data; Muramidase; Recombinant Proteins; Sequence Alignment; Substrate Specificity; Temperature

Topics: Animals; Bacterial Infections; Enteritis; Humans; Intestines; Muramidase; Peyer's Patches

Philasterides dicentrarchi is a histophagous scuticociliate causes fatal scuticociliatosis in farmed olive flounder Paralichthys olivaceus. The average monthly prevalence of scuticociliatosis due to P. dicentrarchi infections was increased from May to July (40+/-3.1% to 79.4+/-1.7%) and it decreased from August to November (63+/-2.3% to 30+/-2.6%) in olive flounder farms at Jeju Island, South Korea during 2000-2006. The prevalence of mixed infection along with Vibrio spp. bacterial infection was 49+/-7.2% than that of other mixed infection. At present no effective control measure for P. dicentrarchi infection has been described and large production losses continue. In the present study, formalin, hydrogen peroxide and Jenoclean chemotheraputants were used for bath treatment. Among Jenoclean at a low concentration of 50ppm proved effective. The results were confirmed with in vitro motility assessments and morphological changes scoring system in P. dicentrarchi. On the other hand, similar trend was noted following hydrogen peroxide treatment at this concentration, but formalin was only moderately effective. Either hydrogen peroxide or Jenoclean are the promising compounds effective at low concentrations with short application time for P. dicentrarchi. Therefore, these substances were evaluated on day 10, 20 and 30 for their ability to enhance innate immune response and disease resistance against P. dicentrarchi in olive flounder after chemotheraputants bath treatment with 100ppm for 30min per day. All the tested immune parameters were enhanced by treatment with Jenoclean, but not formalin and hydrogen peroxide. These findings suggest that Jenoclean bath treatment can be used for ensuring the heath of cultured marine fish against internal parasites such as P. dicentrarchi.

Topics: Animals; Anti-Infective Agents, Local; Bacterial Infections; Ciliophora Infections; Complement System Proteins; Disinfectants; Fish Diseases; Fisheries; Flounder; Formaldehyde; Hydrogen Peroxide; Immunomodulation; Movement; Muramidase; Oligohymenophorea; Phagocytosis; Prevalence; Republic of Korea; Respiratory Burst; Seasons; Seawater; Zeolites

Expression of four reference genes of grass carp, including beta-actin (ACTB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 18S rRNA (18S) and elongation factor-1 alpha (EF1alpha), was studied in tissues of normal individuals and bacteria-infected individuals. EF1alpha had the most stable expressions followed by 18S rRNA then GAPDH; ACTB had the least stability. After being infected with bacteria, the grass carp showed minimal changes in expression levels of EF1alpha in the liver and head kidney, while ACTB had the most stable expressions in spleen but the least stable in liver. EF1alpha is thus the optimal reference gene in quantitative real-time PCR analysis to quantitate the expression levels of target genes in tissues of grass carp.

Topics: Animals; Bacterial Infections; Bacterial Toxins; Carps; Escherichia coli Proteins; Fish Diseases; Fish Proteins; Gene Expression Profiling; Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating); Muramidase; Reference Standards; Reproducibility of Results; Reverse Transcriptase Polymerase Chain Reaction

The immunotropic effects of the probiotic complex Bactistatin (the complex contains metabolites of Bacillus subtilis) used simultaneously with oral doxycycline during different periods of time (1, 5, 10 and 20 days) were estimated. The dynamics of the changes in the nonspecific immunity factors under the effect of the above mentioned products or their combination (bactistatin + doxycycline) during the treatment of different duration was demonstrated. It was found that the oral administration of the metabolic probiotic bactistatin to experimental animals during 1-10 days increased the activity of the nonspecific resistance factors. The immunotropic effects of the product were evident at the level of the cells of the blood phagocytic system and the processes related to synthesis of such enzymes as lysozyme and myeloperoxidase and their release into the blood stream. Comparatively rapid increase of the functional activity of the factors was registered even after a single administration of the product. When the combination of the products (bactistatin + doxycycline) was administered to the animals during a fixed period of time (10 days) significant activation of the nonspecific immunity factors was observed. In perspective the findings will allow to optimize the basic regimens of antibacterial therapy and urgent (postcontact) prevention of infectious diseases.

Topics: Animals; Anti-Bacterial Agents; Bacillus subtilis; Bacterial Infections; Doxycycline; Immunity, Innate; Immunologic Factors; Male; Mice; Muramidase; Peroxidase; Phagocytes; Probiotics; Time Factors

A pilot trial of efficacy of the drugs lisobact and stomatidin in local treatment of acute pharyngitis and combined therapy of tonsillitis and paratonsillar abscess included 82 patients with tonsillitis (n=30), paratonsillar abscess (n=30) and acute pharyngitis (n=22) aged 15-72 years. Effectiveness of the treatment was assessed by changes in clinical symptoms, pharyngoscopic picture and results of bacteriological studies. It was found that treatment with lisobact and stomatidin diminished considerably bacterial contamination of the paratonsillar abscess and pharyngeal mucosa. Local treatment with lisobact and stomatidin for paratonsillar abscess in combination with systemic antibacterial drug reduces the time of hospital stay, in tonsillitis patients - of disability. High compliance to lisobact and stomatidin treatment was observed.

Topics: Adolescent; Adult; Aged; Anti-Infective Agents; Bacterial Infections; Female; Hexetidine; Humans; Male; Middle Aged; Muramidase; Pharyngeal Diseases; Pilot Projects

Whether endogenous deficiency of adrenal corticosteroid by unilateral adrenalectomy leads to any modulation of macrophage response is not clear and needs investigation in detail. We performed unilateral adrenalectomy on male Swiss albino rats. Fractions of splenic macrophages were isolated and their functional activities were determined. To test the effect of adrenal hormone insufficiency (after unilateral adrenalectomy) on the cell mediated and humoral immune response, sheep red blood cells were injected, then the delayed type hypersensitivity (DTH) response and the number of antibody secreting plasma cells were determined. Studies reported herein indicate that in vivo glucocorticoid (GC) insufficiency due to unilateral adrenalectomy decreases chemotactic migration, myeloperoxidase enzyme release, and lysozyme release from rat splenic macrophages that were also related to the induction of cell mediated and humoral immune responses. The maximum number of plaque was obtained from control cells isolated from spleen after 10 days from the control rats, whereas the number of plaque was decreased in spleens isolated 20 days after unilateral adrenalectomy. Our study also showed time dependent decrease in foot pad swelling in the unilaterally adrenalectomized rats where endogenous GC was reduced with respect to control indicating reduced DTH response in case of GC insufficiency. We found slower clearance of bacterial burden from the blood and spleen isolated from unilaterally adrenalectomized rats with respect to control. Thus on one hand partially GC insufficient animals show altered macrophage response and on the other hand it heightens the persistence (in vivo) of Staphylococus aureus. The study may be helpful in understanding that adrenal corticosteroid insufficiency due to adrenalectomy interferes with immune functions, which may also support the hypothesis that endogenous GC plays a role in regulating immune response.

Topics: Adrenal Insufficiency; Adrenalectomy; Animals; Antibody Formation; Bacterial Infections; Chemotaxis, Leukocyte; Glucocorticoids; Immunity, Cellular; Macrophages; Male; Muramidase; Peroxidase; Rats

JB-1 and GC2, which were equated with Bacillus sp. and Aeromonas sobria respectively, were recovered from the digestive tract of rainbow trout, Oncorhynchus mykiss and ghost carp, Cyprinus sp. respectively, and demonstrated effectiveness as probiotics for the control of infections caused by Aeromonas salmonicida, Lactococcus garvieae, Streptococcus iniae, Vibrio anguillarum, Vibrio ordalii and Yersinia ruckeri. When administered to rainbow trout (average weight = 12 g) for 14 days in feed dosed at 2 x 10(8) cells g(-1) of feed, JB-1 led to a reduction in mortalities to 0-13% after challenge with a range of bacterial pathogens compared to 80-100% mortalities of the controls. Similarly, use of GC2 reduced mortalities to 0-16% following the challenge compared to 80-100% mortalities of the controls. The mode of action reflected nutrition, production of inhibitory substances and stimulation of the innate immune responses. Specifically, JB-1 and especially GC2 were positive for siderophore and chitinase production, and increased lysozyme, phagocytic and respiratory burst activity.

Topics: Aeromonas; Animal Feed; Animals; Anti-Infective Agents; Bacillus; Bacteria; Bacterial Infections; Erythrocyte Count; Fish Diseases; Leukocyte Count; Macrophages; Muramidase; Oncorhynchus mykiss; Probiotics; Respiratory Burst; Siderophores; Survival Analysis

We established a transgenic zebrafish strain expressing chicken lysozyme gene under the control of the Japanese flounder keratin gene promoter, and investigated its resistance to a pathogenic bacterial infection. To generate the lysozyme transgenic construct, Japanese flounder keratin promoter was linked to both the hen egg white (HEW) lyoszyme gene and green fluorescence protein (GFP) gene used as a selection marker for the transgenic strains, in a recombinant plasmid. The recombinant plasmid was microinjected into fertilized zebrafish eggs. In F2 transgenic zebrafish, GFP expression was strong in the epithelial tissues, liver and gill from the embryonic stage to the adult stage. The expressions of HEW lysozyme and GFP mRNA were confirmed in the liver and skin by RT-PCR. Western blot analysis showed that both HEW lysozyme and GFP were present in protein extracts from the liver of transgenic zebrafish, but not in protein extracts from the muscle. The lytic activity of protein extracts from the liver (assessed by a lysoplate assay using Micrococcus lysodeikticus as a substrate) was 1.75 times higher in F2 transgenic zebrafish than in the wild type. In a challenge experiment, 65% of the F2 transgenic fish survived an infection of Flavobacterium columnare and 60% survived an infection of Edwardsiella tarda, whereas 100% of the control fish were killed by both pathogens. However, the survival rates of the transgenic fish were not significantly higher when higher concentrations of bacteria were used.

Topics: Animals; Animals, Genetically Modified; Bacterial Infections; Chickens; Female; Genetic Techniques; Green Fluorescent Proteins; Immunity, Innate; Male; Muramidase; Plasmids; Promoter Regions, Genetic; RNA, Messenger; Time Factors; Zebrafish

Submucosal glands are abundant (approximately 1 gland/mm2) secretory structures in the tracheobronchial airways of the human lung. Because submucosal glands express antibacterial proteins, it has been proposed that they contribute to lung defense. However, this concept is challenged by the fact that mice do not have submucosal glands in their bronchial airways, yet are quite resistant to bacterial lung infection. The contribution of airway submucosal glands to host defense is also debated as a pathophysiologic component of cystic fibrosis lung disease. Here, we asked whether submucosal glands protect airways against bacterial infection. By comparing tracheal xenograft airways with and without glands, we found that the presence of glands enhanced bacterial killing in vivo and by airway secretions in vitro. Moreover, immunodepletion studies suggested that lysozyme is a major antibacterial component secreted by submucosal glands. These studies provide evidence that submucosal glands are a major source of antibacterials critical for maintaining sterile airways.

Topics: Animals; Bacterial Infections; Bronchi; Ferrets; Muramidase; Rats; Respiratory Mucosa; Trachea; Transplantation, Heterologous

Paneth cells of intestinal crypts contribute to host defense by producing antimicrobial peptides that are packaged as granules for secretion into the crypt lumen. Here, we provide evidence using light and electron microscopy that postsecretory Paneth cell granules undergo limited dissolution and accumulate within the intestinal crypts of cystic fibrosis (CF) mice. On the basis of this finding, we evaluated bacterial colonization and expression of two major constituents of Paneth cells, i.e., alpha-defensins (cryptdins) and lysozyme, in CF murine intestine. Paneth cell granules accumulated in intestinal crypt lumens in both untreated CF mice with impending intestinal obstruction and in CF mice treated with an osmotic laxative that prevented overt clinical symptoms and mucus accretion. Ultrastructure studies indicated little change in granule morphology within mucus casts, whereas granules in laxative-treated mice appear to undergo limited dissolution. Protein extracts from CF intestine had increased levels of processed cryptdins compared with those from wild-type (WT) littermates. Nonetheless, colonization with aerobic bacteria species was not diminished in the CF intestine and oral challenge with a cryptdin-sensitive enteric pathogen, Salmonella typhimurium, resulted in greater colonization of CF compared with WT intestine. Modest downregulation of cryptdin and lysozyme mRNA in CF intestine was shown by microarray analysis, real-time quantitative PCR, and Northern blot analysis. Based on these findings, we conclude that antimicrobial peptide activity in CF mouse intestine is compromised by inadequate dissolution of Paneth cell granules within the crypt lumens.

Topics: Animals; Bacteria; Bacteria, Aerobic; Bacterial Infections; Colony Count, Microbial; Cytoplasmic Granules; Down-Regulation; Intestinal Mucosa; Intestines; Mice; Mice, Inbred CFTR; Microscopy, Electron; Microvilli; Muramidase; Paneth Cells; Peptide Fragments; Protein Precursors; RNA, Messenger; Salmonella typhimurium

More than 70 years ago, Alexander Fleming discovered lysozyme and proposed that nonpathogenic bacteria fail to cause disease because they are very susceptible to destruction by lysozyme, an enzyme that is one of the principal proteins of phagocytes. Although much has been learned about the effects of lysozyme in vitro, its biological role in vivo has not been determined. We examined transgenic mice deficient in lysozyme M after challenge by the normally nonpathogenic and highly lysozyme-sensitive bacterium Micrococcus luteus. Despite partial compensation by newly expressed lysozyme P in macrophages, lysozyme M-deficient mice developed much more severe lesions than wild-type mice. The tissue injury was due to the failure of lysozyme M-deficient mice to inactivate peptidoglycan, resulting in an intense and prolonged inflammatory response. Our data indicate that tissue injury is normally limited by prompt degradation of bacterial macromolecules that trigger innate immunity and inflammation.

Topics: Animals; Bacterial Infections; Disease Susceptibility; Gene Expression; Green Fluorescent Proteins; Inflammation; Luminescent Proteins; Macrophages; Mice; Mice, Inbred C57BL; Mice, Transgenic; Micrococcus luteus; Muramidase; Neutrophils; Peptidoglycan; Recombinant Fusion Proteins

Bacterial samples were obtained from the tonsillar surfaces of seven patients (four males, three females; median age 18 years, range 15 to 21 years) suffering from acute infectious mononucleosis with concomitant pharyngotonsillitis, and from five healthy controls. By using gold-labelled antiserum to human lysozyme and lactoferrin, micro-organisms on the tonsillar surfaces coated with these antibacterial substances could be identified by tracing the gold particles in the transmission electron microscope. In healthy individuals, most of the bacteria were coated with lysozyme and significantly more bacteria were coated with lysozyme than with lactoferrin (p < 0.01). In patients there was a non-significant reduction in lysozyme-coating of the bacteria, whereas lactoferrin-coating was significantly increased (p < 0.01). Changes in the lysozyme and/or lactoferrin coating of the tonsillar surface bacteria on the palatine tonsils during infectious mononucleosis cannot explain the tendency to immense local bacterial colonization with commensals and proneness to bacterial penetration into the epithelial cells.

Topics: Adolescent; Adult; Bacteria; Bacterial Infections; Epstein-Barr Virus Infections; Female; Humans; Immunohistochemistry; Lactoferrin; Male; Muramidase; Palatine Tonsil; Statistics, Nonparametric; Tonsillitis

The aim of this study was to evaluate the diagnostic capacity of a number of blood components such as soluble adhesion molecules, interleukin-6 (IL-6), myeloperoxidase (MPO) and lysozyme in the distinction of acute bacterial and viral infections. Blood was taken from 115 acutely infected patients at admission before any treatment and in some cases on several consecutive days. 35 of the patients had a definite viral cause for their infection and 66 a bacterial cause. All variables were raised in patients with acute bacterial infections. Soluble vascular cell adhesion molecule-1 (sVCAM-1), sE-selectin, lysozyme and MPO were also raised in acute viral infections, but for sE-selectin and MPO less so than in bacterial infections. Evaluation of the diagnostic power showed that for MPO and IL-6 at cut-offs of 1300 microg/l and 100 ng/l, respectively, the positive predictive value was 97% and 100% and the negative predictive value 78% and 76%, respectively, in the classification of acute bacterial infections. In the distinction between viral or bacterial causes of acute infections in otherwise healthy subjects serum measurements of MPO and IL-6 are valuable tools and should be considered as diagnostic aids in the routine setting. The soluble adhesion molecules did not offer any further information in this respect.

Topics: Acute Disease; Adolescent; Adult; Aged; Aged, 80 and over; Bacterial Infections; Biomarkers; Cell Adhesion Molecules; Child; Cytokines; Diagnosis, Differential; E-Selectin; Female; Humans; Intercellular Adhesion Molecule-1; Interleukin-6; Male; Middle Aged; Muramidase; Peroxidase; Predictive Value of Tests; Vascular Cell Adhesion Molecule-1; Virus Diseases

Pathogenesis substantiation and clinical efficiency of transendoscopic treatment of the patients with gastroduodenal ulcers relapse by lysozyme compound with molecular iodine and polyiodides are presented in this paper. The relapse of peptic ulcer was accompanied by lysozyme decrease and helicobacter's sowing increase in stomach and duodenal mucosa, as well as activity mucosa flora increase, especially in periulcer's region. This fact has drown near ulcer's defect and infected wound. Significant microbicidal and sorptional effects to the revealed strains of microorganisms, mucous membrane barrier properties increase and shortening of the peptic ulcer's scarring time on 8 days were demonstrated after transendoscopic treatment of the peptic ulcer with iodine lysozyme 3-4 times.

Topics: Anti-Infective Agents, Local; Bacterial Infections; Combined Modality Therapy; Endoscopy; Gastric Mucosa; Humans; Iodides; Muramidase; Peptic Ulcer; Secondary Prevention

The presentation of infection in immunocompromised patients can be subtle. Patients often undergo extensive testing and empiric treatment for rejection and infection while awaiting the results of the biopsy and culture results. Delay in diagnosis of either entity can result in a worse clinical outcome. Lysozyme activity has been found to be both a sensitive and a specific marker for infection in laboratory animals and trauma patients. Our goal was to determine whether lysozyme activity could serve as a reliable marker for infection in immunocompromised organ transplant recipients.. Transplant recipients from three clinical categories were enrolled in this study. Group 1 (n = 16) were patients hospitalized for sepsis (culture-positive), and Group 2 (n = 13) for biopsy-proven rejection. Group 3 (n = 51) were recipients who had routine blood sampling in the clinic. In Groups 1 and 2, blood was collected within 24 h of hospital admission and centrifuged, and serum samples were stored at 80 degrees C until processing. Lysozyme activity was assayed by turbidimetric measurement on a sample of a standard suspension (0.15 mg/ml) of Micrococcus lysodeikticus in buffer using a spectrophotometer to read the optical density at 450 nm. The lysozyme activity level was then determined by the measuring activity at 1 min subtracted from activity at 4 min. White blood cell count was determined by using a flow cytometer. Statistical comparisons between groups were made using paired Student's t test.. Serum lysozyme was found to be significantly elevated in Group 1; the mean level of activity was 60.1 +/- 13 (P < 0.05) compared to the level of activity in Group 2, mean 41.1 +/- 11, and Group 3, mean 40.8 +/- 13. A level of 45 units of activity/ml of serum or above indicated infection and not rejection in the patients admitted to the hospital.. These findings indicate that the lysozyme activity assay appears to be useful in differentiating infection from rejection in transplant recipients.

Topics: Adolescent; Adult; Aged; Bacterial Infections; Graft Rejection; Humans; Middle Aged; Muramidase; Organ Transplantation; Reference Values; Surgical Wound Infection; Virus Diseases

To determine immunocytochemically whether preterm and newborn infants with necrotising enterocolitis (NEC) show differences in numbers of lysozyme positive Paneth cells compared with normal controls, and to relate the findings to the possibility that lysozyme deficiency may facilitate the bacterial infections thought to be associated with this condition.. Tissues from 10 infants with NEC and from 11 matched controls were sectioned and stained immunocytochemically for lysozyme. Differences in the numbers of Paneth cells and degree of lysozyme positivity in the tissues were assessed.. Tissues from NEC patients showed no, or very few, lysozyme positive Paneth cells, whereas controls showed strong positive staining.. A deficiency or developmental defect in Paneth cells, resulting in an absence of lysozyme, may render the intestine more susceptible to bacterial infection, allowing organisms to adhere and translocate across the mucosa. Such enhancement of infection may contribute to the pathogenesis of NEC.

Topics: Bacterial Infections; Biomarkers; Enterocolitis, Necrotizing; Humans; Immunohistochemistry; Infant, Newborn; Intestine, Small; Muramidase; Paneth Cells

The persistent properties of the intestinal microflora as a mechanism of adaptation to the host's antimicrobial factors are substantiated. The results of determination of antilysozyme and anticomplementary activities and the inactivating abilities of the bactericidal component of interferon in enteric bacteria isolated in intestinal dysbacteriosis are outlined. Changes were found in the population structure of the Escherichia flora in relation to the severity of dysbacteriosis and a high prevalence of persistent signs were revealed in enteric bacteria. There was a correlation between the persistent signs of bacteria and the severity of intestinal microbiocenotic abnormalities. The factors of microbial persistence are proposed to be used as markers of a dysbiotic process.

Topics: Antiviral Agents; Bacteria; Bacterial Infections; Bacterial Physiological Phenomena; Biomarkers; Drug Resistance, Microbial; Feces; Humans; Interferons; Intestines; Muramidase

Topics: Animals; Bacterial Infections; Biological Assay; Biomarkers; Copper; Micrococcus; Muramidase; Polychaeta

Topics: Antibodies; Bacterial Infections; Female; Humans; Immunoglobulin A, Secretory; Infant, Newborn; Lactoferrin; Lymphocytes; Macrophages; Milk, Human; Muramidase; Neutrophils

Topics: Bacillus megaterium; Bacillus subtilis; Bacterial Infections; Blood Proteins; Carrier State; Child; Defensins; Environmental Monitoring; Epidemiological Monitoring; Histones; Humans; Muramidase; Nasal Mucosa; Risk; Siberia; Staphylococcus aureus

Topics: Bacteria; Bacterial Infections; Biological Products; Feces; Fetal Diseases; Humans; Immunoglobulin A, Secretory; Infant, Newborn; Intestines; Lactobacillus acidophilus; Muramidase; Risk Factors

Both the immunoglobulins and non-specific antibacterial factors in milk from cows immunized with pathogenic oral bacteria have the potential to influence the oral microflora during passive immunization studies. The first six milks after calving were collected from 2 cows immunized with adjuvant and from 14 cows immunized with adjuvant and heat-killed strains of periodontopathic Actinomyces, Porphyromonas, Prevotella, and Fusobacterium. Analysis of the products from the first to the sixth milks revealed that the protein and lysozyme content decreased approximately 66 and 72%, respectively; the mean specific activity of the enzyme remained relatively constant. In contrast, the mean lactoperoxidase activity increased 2.3-fold in the second milking and increased further in the fourth and sixth milkings. The mean iron-binding activity increased 1.2-fold from the first to the second milkings and then decreased 3.6-fold through the sixth milking. Cows immunized with adjuvant alone showed similar responses. Per unit volume, the milk contained approximately 150 times less lysozyme than whole human saliva obtained from six subjects but higher concentrations of lactoperoxidase and iron-binding components. Purified bovine nonspecific factors prevented the growth of the bacteria used for immunization when bacteria were tested at concentrations similar to those found in saliva and milk. Because bovine nonspecific antibacterial factors could influence both the pathogenic target bacteria and the indigenous microflora in oral passive immunization studies with bovine immunoglobulins, the presence of these proteins should be considered.

Topics: Actinomyces; Adjuvants, Immunologic; Animals; Bacteria; Bacterial Infections; Bacteroides; Carrier Proteins; Cattle; Colostrum; Fusobacterium; Humans; Immunization, Passive; Iron; Iron-Binding Proteins; Lactoperoxidase; Milk; Milk Proteins; Mouth; Muramidase; Saliva; Transferrin-Binding Proteins

Lysozyme, a bacteriolytic protein discovered by Fleming in 1922 and found to be phylogenetically ancient and almost ubiquitous among living organisms, is probably the most studied enzyme in biology and medicine. Evidence of its involvement in resistance to bacterial infection is compelling but remains indirect. Muramyl peptides (fragments of bacterial cell wall peptidoglycan) exert many effects on the immune system and the CNS, and appear to contribute to non-specific resistance to infection, fever, fatigue, and the pathogenesis of bacterial infection. Synthetic muramyl peptide analogues are currently used as adjuvants in vaccine trials in humans. Several pathological conditions are associated with changes in lysozyme concentrations, and egg-white lysozyme treatment has been tried on a small scale. With the cloning of the human lysozyme gene in yeast cells the enzyme can now be produced on a large scale, which will enable its therapeutic applications to be evaluated.

Topics: Bacterial Infections; History, 20th Century; Humans; Muramidase; Neoplasms

The effect of trichlorphon, one of the most widely used organophosphorus insecticides, on the nonspecific immune response in carp (Cyprinus carpio) was studied. The effect of 20,000 ppm trichlorphon on the immune response was followed for 3 and 56 days after intoxication. The effect of 10,000 ppm trichlorphon on the nonspecific immune response of carp experimentally infected by Pseudomonas alcaligenes and Aeromonas punctata was also examined. Leucocyte number, phagocytic ability of neutrophils, percentage NBT-positive PMN cells, phagocytic index, lysozyme level in serum, and ceruloplasmin activity in plasma were examined on Days 2, 4, 6, 8, 10, 14, 18, 22, and 26 after carp were exposed. After intoxication leukopenia was observed as decreases in phagocytic ability of neutrophils and in phagocytic index. Lysozyme level in serum was also decreased compared to that of control. The percentage of NBT-positive PMN cells decreased when the ceruloplasmin activity in plasma increased in intoxicated fish.

Topics: Aeromonas; Animals; Bacterial Infections; Carps; Ceruloplasmin; Cyprinidae; Leukocyte Count; Muramidase; Neutrophils; Phagocytosis; Pseudomonas Infections; Trichlorfon

Two comparable groups made up of 15 neonates with intestinal infections induced by opportunistic bacteria were under observation. The children of group 1 received lysozyme in a dose of 25 mg/kg a day for 7-10 days together with conventional therapy Lysozyme appeared to promote the reduction of the disease duration and the rise of the phagocytic reserves of peripheral blood neutrophils in the children examined.

Topics: Adjuvants, Immunologic; Bacterial Infections; Enterocolitis; Humans; Immune Tolerance; Infant, Newborn; Muramidase; Phagocytosis; T-Lymphocytes

Topics: Bacterial Infections; History, 19th Century; History, 20th Century; Humans; Muramidase; Penicillins; Scotland

Topics: Adolescent; Adult; Aged; Anti-Bacterial Agents; Bacterial Infections; Bandages; Drug Therapy, Combination; Humans; Middle Aged; Muramidase; Suppuration; Wound Healing; Wound Infection

Cerebrospinal fluid lysozyme (CSF-LZM) concentrations were determined in 62 controls, 28 viral meningitis and 22 bacterial meningitis, as compared to CSF lactic acid routinely used. CSF-LZM measurement was performed by a rapid turbidimetric assay which required 50 microliters CSF only. The mean CSF-LZM concentration of the control group was 0.23 mg/l, the highest value being 0.65 mg/l. The mean LZM levels in viral meningitis were 1.10 mg/l, never exceeding 3 mg/l. The range of pretreatment LZM levels in bacterial meningitis was 7.2 to 65 mg/l and above 3 mg/l in all cases 48 h after treatment. On the 6th day after admission, 12 of 16 samples showed abnormal values. The CSF-LZM assay seems to be of more value than that of lactic acid. Thus, before treatment, LZM concentrations were 10 to 100 fold higher than that of the normal values, with persistent high levels on the 2nd and even on the 6th day of treatment (whereas lactic acid values were all normal on day 6).

Topics: Analysis of Variance; Bacterial Infections; Child; Child, Preschool; Humans; Infant; Lactates; Lactic Acid; Meningitis; Muramidase; Photometry; Protein C; Virus Diseases

Topics: Adolescent; Adult; Bacterial Infections; Blood Proteins; Convalescence; Focal Infection; Humans; Middle Aged; Muramidase; Neutrophils; Peroxidase; Prognosis

The proliferation of lymphocytes induced by Propionibacterium acnes (P. acnes) was measured by the in vitro incorporation of 3H-thymidine. The mean response rate of alveolar lymphocytes obtained by bronchoalveolar lavage was 2.23 +/- 0.89 in nine untreated sarcoidosis patients, 0.85 +/- 0.17 in five sarcoidosis patients given corticosteroids and 0.78 +/- 0.29 in 11 controls. The proliferation was significantly enhanced in the untreated patients compared to both the treated patients (p less than 0.01) and controls (p less than 0.001), but there was no significant difference in response rates between the treated patients and controls. The response rate of alveolar lymphocytes was significantly higher in four active patients (3.05 +/- 0.61) than in four inactive patients (1.77 +/- 0.44) (p less than 0.05) and in the controls (p less than 0.001). In sarcoidosis patients, the response rates showed a good correlation with activities of serum lysozyme (r = 0.695, p less than 0.01), and with percentages of lymphocytes in bronchoalveolar lavage fluid (r = 0.591, p less than 0.05). There was a low correlation between angiotensin-converting enzyme activities and the response rates (r = 0.508, p less than 0.1). Neither peripheral blood lymphocytes in sarcoidosis patients nor in controls showed any response to P. acnes, but alveolar lymphocytes of the untreated active sarcoidosis patients were sensitive to P. acnes. The lymphocytes activated by P. acnes may play a central role in the induction of alveolitis in sarcoidosis patients.

Topics: Adult; Aged; Bacterial Infections; Cell Division; Female; Humans; Lymphocytes; Male; Middle Aged; Muramidase; Peptidyl-Dipeptidase A; Prednisolone; Propionibacterium acnes; Pulmonary Alveoli; Sarcoidosis

Topics: Amoxicillin; Ampicillin; Animals; Bacterial Infections; Bromelains; Kinetics; Male; Muramidase; Rats; Skin

The interaction of seven serum-sensitive Aeromonas strains with the complement system was investigated using a 2-h quantitative assay. Of the strains tested, four isolates activated both the alternative and classical pathways, two activated only the alternative pathway, and one strain was sensitive to the bactericidal action of complement through the classical pathway only. Two of the four Aeromonas caviae strains were such efficient activators of the complement system that when challenged with human sera deficient in normal concentrations of C3 and C4, they were still subject to complement-mediated bacterial lysis. This phenomenon, in conjunction with previous studies on complement activation by Aeromonas spp., may help account for the decreased incidence observed of systemic disease caused by Aeromonas caviae.

Topics: Aeromonas; Bacterial Infections; Blood Bactericidal Activity; Complement Activation; Complement C3; Complement C4; Complement Pathway, Alternative; Complement Pathway, Classical; Elapid Venoms; Humans; Muramidase

A rat model of chronic pulmonary infection (CPI) initiated by Pseudomonas aeruginosa embedded in agar beads was used to test the effect of ozone on lysosomal enzyme levels in alveolar macrophages (AM). CPI was induced by intratracheal instillation of a 0.1-ml suspension of infected beads into the left lung. Ten days after infection half the rats were exposed to atmospheres of air and half to 0.64 ppm ozone for 4 weeks. Enzyme levels were measured using a scanning cytospectrophotometer linked to PDP/11 computer. Measurement of lysozyme in individual rat AM in situ showed a significant decrease in cell size and enzyme content in ozone-exposed uninfected animals. Cell size and enzyme content of ozone-exposed animals with CPI were further reduced, suggesting a synergistic effect between ozone exposure and chronic infection.

Topics: Animals; Bacterial Infections; Chronic Disease; Lung Diseases; Macrophages; Male; Monocytes; Muramidase; Ozone; Pulmonary Emphysema; Rats; Rats, Inbred Strains

A total of 176 Gram-positive, catalase positive cocci strains, isolated from sheep were studied by different routine tests for the differentiation of staphylococci and micrococci, comparing their validity and usefulness. By glucose fermentation and growth in the anaerobic portion of thioglycolate 85 and 73.6% respectively of coagulase negative staphylococci were misclassified as Micrococcus spp. Susceptibility to lysostaphin was an adequate test for the differentiation of the strains. Atypical results in the production of acid from glycerol/erythromycin were obtained in 11.8% of the coagulase negative strains and 16.7% of micrococci. The combined use of the selective media furazolidone agar and Schleifer and Krämer medium resulted in a fast and useful separation of ovine staphylococci and micrococci. The bacteriolytic activity misclassified 32.2% of the coagulase negative strains.

Topics: Animals; Bacterial Infections; Bacteriolysis; Coagulase; Culture Media; Erythromycin; Glucose; Glycerol; Lysostaphin; Micrococcus; Muramidase; Sheep; Sheep Diseases; Staphylococcal Infections; Staphylococcus

Neutrophil superoxide production has been recognized as an important pathway for microbicidal activity and regulation of the local inflammatory environment. To investigate neutrophil superoxide production in sepsis, we studied 22 patients with intra-abdominal infections, and correlated superoxide production with chemotactic response and granular enzyme content. Our results showed that neutrophils from infected patients had specific loss of chemotactic response to C5a, and were deficient in the granular enzymes, lysozyme, and beta-glucuronidase. Superoxide production in response to opsonized zymosan was intact, but response to the chemoattractant N-formyl-methionyl-leucyl-phenylalanine was markedly depressed. This could be reversed in vitro by the addition of cytochalasin B. These results suggest that down regulation of exocytosis of superoxide to nonphagocytic stimuli occurs during sepsis, possibly protecting the host from tissue injury due to oxide radical release. Superoxide response to phagocytic stimulation was intact.

Topics: Abdomen; Adult; Aged; Bacterial Infections; Chemotaxis, Leukocyte; Complement C5; Complement C5a; Cytochalasin B; Female; Glucuronidase; Humans; Male; Middle Aged; Muramidase; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils; Postoperative Complications; Superoxides; Zymosan

Bronchial secretions obtained during bronchoscopic examination of 60 children suffering from respiratory tract infections were studied for the concentration of immunoglobulins, anti-proteolytic factors, lactoferrin, and lysozyme. Eleven children having bronchial asthma without a history of chronic or recurrent infections of the respiratory tract were designated as a control. The results were analysed in relation to clinical diagnosis (chronic bronchitis, bronchitis, bronchiectasis) or to the local status of bronchial mucosa at the time of bronchoscopy (no inflammation, inflammation, inflammation with documented bacterial infection). The statistical analysis of the results revealed a decrease of lactoferrin and locally produced IgA in the group of children suffering from bronchitis and chronic bronchitis. Samples infected with Haemophilus species had significantly higher concentration of lactoferrin than any other group. Similarly, albumin in this group was higher than in the other group except that other bacteria were present. Samples infected with Haemophilus also had increased concentrations of S-IgA, IgG, and anti-proteolytic factors when compared with the group without local inflammation.

Topics: Bacterial Infections; Bronchi; Bronchitis; Child; Child, Preschool; Humans; Immunoglobulin A; Immunoglobulin A, Secretory; Lactoferrin; Mucus; Muramidase; Respiratory Tract Infections; Serum Albumin

Endolymphatic infusions of an antibacterial complex (antibiotic--lysozyme--proteinase inhibitor) resulted in recovery of 92,6% of patients after a complex treatment of diffuse peritonitis and sepsis. Gauze-sorbent tampons used in empyema of pleura give rapid cleaning of the cavity walls from pyo-necrotic masses and decreased the activity of the inflammatory process.

Topics: Anti-Bacterial Agents; Bacterial Infections; Drug Combinations; Empyema; Foot; Humans; Injections, Intralymphatic; Muramidase; Peritonitis; Protease Inhibitors

A turbidimetric technique has been adapted to yield maximum sensitivity for the measurement of lysozyme in cerebrospinal fluid. One hundred and ninety-eight patients were studied over a total period of 9 months using this technique. In addition to the considerably elevated levels known to occur in cases of bacterial and fungal meningitis, increased activity was also demonstrated in cases of subarachnoid haemorrhage and in certain inflammatory conditions. Normal or marginally increased levels were seen in cases of viral meningitis and encephalitis.

Topics: Bacterial Infections; Encephalitis; Humans; Meningitis; Meningitis, Viral; Muramidase; Nephelometry and Turbidimetry; Nervous System Diseases

Meningococci and Haemophilus influenzae may invade the subarachnoid space during the bacteriaemic phase without impairment of the blood-CSF barrier and in the absence of any leucocyte reaction. In pneumococcal meningitis the CSF may also contain less than 100 cells/microliter despite the presence of "pure bacterial cultures", but the barrier is completely broken when the serum/CSF concentration ratio is below 10. A clinical analysis of eight patients with fewer than 100 cells/microliter revealed that the first symptoms of meningitis appeared at least 3 days prior to the diagnostic lumbar puncture. There was a strong neutrophilic reaction in the blood with a prevalence of juvenile forms in most cases, indicating intact antibacterial defence mechanisms. Within 24 h after the start of antibiotic therapy the cell number rose above 2000/microliter accompanied by disappearance of pneumococci. Six of the eight patients died. In three cases autopsy revealed thick layers of pus over the convexities, indicating a compartmental separation of the ventricles and the spinal subarachnoid space. In one case of late diagnosed bacterial meningitis with a pleocytosis of 430/microliter the CSF lysozyme level was seven times higher than compatible with this cell number. Hyperphagocytosis and cellular disintegration is thought to cause the leucopenia within the spinal CSF compartment. "Apurulent bacterial meningitis" can be seen as a disease entity that is a diagnostic pitfall and also a prognostic sign.

Topics: Adult; Aged; Bacterial Infections; Blood-Brain Barrier; Female; Glucuronidase; Humans; Leukocyte Count; Leukopenia; Male; Meningitis; Meningitis, Haemophilus; Meningitis, Listeria; Meningitis, Pneumococcal; Middle Aged; Muramidase; Prognosis

The significance of the measurement of lactate, lysozyme and PHI in CSF for differential diagnosis of meningitis was examined in 58 cases of viral, 36 of bacterial and 5 of tuberculous etiology. In the early phase of the illness CSF lactate was found to be the most sensitive parameter for distinction of viral from bacterial or tuberculous meningitis respectively. Except for one case CSF lactate exceeded 3.8 mmol/l in all cases of bacterial etiology, whereas this value was never reached in any case of viral meningitis. While lactate concentration was maximal on the day of admission and declined continuously thereafter, PHI activity reached its maximum on the third day after beginning of the therapy. At this time all patients with a bacterial or tuberculous meningitis had PHI activities about 50 U/l. This value wasn't exceeded in any case of viral meningitis. In a few cases some days after onset of therapy a distinction of bacterial meningitis from viral forms was still possible by PHI determination but not by lactate measurement. Determination of lysozyme also could be helpful in the later phase of the disease.

Topics: Bacterial Infections; Cryptococcosis; Diagnosis, Differential; Glucose-6-Phosphate Isomerase; Humans; Lactates; Lactic Acid; Meningitis; Meningitis, Viral; Muramidase; Mycoplasma Infections; Tuberculosis, Meningeal

The paper discusses the data on secretion of immunoglobulin and lysozyme in the upper respiratory tract of patients with acute leukemia. The data were used in the evaluation of certain biological preparations intended for prevention of infectious complications.

Topics: Bacterial Infections; Bacteriophages; Humans; Immunoglobulin A, Secretory; Leukemia, Lymphoid; Leukemia, Myeloid, Acute; Mucous Membrane; Muramidase; Pharynx; Pseudomonas aeruginosa; Staphylococcus Phages

Serum levels of lactoferrin, lysozyme and myeloperoxidase have been established in 31 healthy children. On average, serum lactoferrin was 330 micrograms/1, serum lysozyme 1638 micrograms/1 and serum myeloperoxidase 174 micrograms/1. Serum myeloperoxidase was, on average, significantly higher in children than in adults (p = 0.01), whereas serum lactoferrin and serum lysozyme were equal to those of adults. In a group of infection-prone children (n = 31), both serum lactoferrin and serum myeloperoxidase, but not the serum lysozyme levels, were significantly lower (p less than 0.001 and p = 0.002, respectively) than those of the reference children in spite of normal intracellular contents and even somewhat higher peripheral blood polymorphonuclear counts. Based on the assumption that serum lactoferrin and serum myeloperoxidase reflect turnover and activity of neutrophil granulocytes, the findings could suggest reduction in these respects and could be one contributing factor to the high infection propensity of these children. Serum levels of the three proteins have also been measured in 10 children with suspected or various forms of manifest leukemia. It is suggested that the levels reflect turnover and stage of maturation of the myeloid and monocytic cells and could, therefore, aid in the understanding and diagnosis of these diseases.

Topics: Adolescent; Adult; Bacterial Infections; Cell Division; Child; Child, Preschool; Female; Humans; Infant; Lactoferrin; Lactoglobulins; Leukemia; Leukocyte Count; Leukocytes; Male; Muramidase; Peroxidase; Peroxidases; Probability

Prominent and global abnormalities in chemotactic, oxidative, and microbicidal activity have been identified in neutrophils from patients with severe sepsis. To evaluate the possible contribution of degranulation as the basis for the observed abnormalities, 12 patients with intrabdominal infection were serially studied and neutrophil chemotaxis, enzyme content, and receptors for FMLP were evaluated. There was a significant correlation between chemotactic response to both activated serum and FMLP with the granular enzymes beta-glucuronidase and lysozyme. For FMLP-directed migration, r = 0.73, P less than 0.001 for lysozyme, and r = 0.59, P less than 0.001 for beta-glucuronidase. There was a similarly significant correlation between loss of lysozyme and an increase in FMLP receptors, previously shown to be a marker for degranulation. These data support the concept that in vivo degranulation, possibly due to effects of circulating chemoattractants on adherent neutrophils, is responsible for the enzymatic and chemotactic loss seen in cells from septic patients. This hypothesis also provides a mechanism to explain the respiratory distress syndrome if degranulation were to occur in the pulmonary capillary bed.

Topics: Bacterial Infections; Biliary Tract Diseases; Chemotaxis, Leukocyte; Colonic Diseases; Cytoplasmic Granules; Duodenal Diseases; Glucuronidase; Humans; Intestinal Diseases; Muramidase; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils; Receptors, Cell Surface; Receptors, Formyl Peptide

The effects of season and variations in the prevalence of infectious disease on the concentrations and daily production of breast-milk immunoproteins were studied in 152 rural Gambian mothers and their children up to 26 months post-partum. IgA, IgG, IgM, C3, C4, lactoferrin, lysozyme and secretory component concentrations and breast-milk volumes were measured longitudinally over a six month period which encompassed dry and rainy seasons. No increase in the production of any immunoprotein was observed at the time of maximum prevalence of serious infectious diseases, especially diarrhoea, in the children. Enhanced secretion of certain immunoproteins was noted in mothers of children aged 9-18 months at the beginning of the rainy season. There was some evidence that this may have been associated with skin sepsis, particularly impetigo, in the children. The production of most immunoproteins fell during the rainy season. This was not the result of declining maternal food intakes as similar decreases were seen for women receiving a dietary supplement.

Topics: Bacterial Infections; Complement C3; Complement C4; Developing Countries; Female; Gambia; Humans; Immunoglobulins; Infant; Infant Nutritional Physiological Phenomena; Infant, Newborn; Lactation; Lactoferrin; Milk, Human; Muramidase; Mycoses; Pregnancy; Rural Population; Seasons; Secretory Component; Virus Diseases

The antiinflammatory roentgenotherapy was used in 150 patients with pyo-inflammatory processes (post-operative inflammatory complications, periappendicular infiltration, hydradenitis, osteo-articular panaritium, mastitis). Good and satisfactory results were obtained in 92,6% of the patients. Positive dynamics of the T-lymphocyte level and increased activity of the blood serum lysozyme proved to be good prognostic signs.

Topics: Adult; Bacterial Infections; Combined Modality Therapy; Female; Humans; Leukocyte Count; Male; Middle Aged; Muramidase; Postoperative Complications; Suppuration; T-Lymphocytes

Topics: Adenoidectomy; Bacterial Infections; Child; Humans; Immunity; Immunoglobulin A, Secretory; Muramidase; Tonsillectomy

The natural resistance of the organism studied in 152 patients with purulent surgical infections against the background of diabetes mellitus was found to be considerably changed. Prodigiozan included in the complex measures of treatment was shown by the author to result in positive dynamics of the indices of humoral defense of the organism, in shortening the terms of treatment in the hospital by 5,2 days on the average. The most pronounced influence on the natural immunity factors and better postoperative results were found following joint employment of lysozyme and prodigiozan. The hospital treatment of this group of patients was 7.3 days shorter.

Topics: Aged; Bacterial Infections; Blood Bactericidal Activity; Combined Modality Therapy; Diabetes Complications; Drug Therapy, Combination; Humans; Immunoglobulins; Middle Aged; Muramidase; Polysaccharides, Bacterial; Prodigiozan; Suppuration

Topics: Adolescent; Bacterial Infections; Child; Child, Preschool; Clinical Enzyme Tests; Humans; Infant; Meningitis; Muramidase

The CSF levels of lactoferrin, lysozyme, and beta 2-microglobulin (beta 2 mu) were measured in patients with evident, probable, or possible inflammatory CNS reactions and compared to those found in neurologically apparently healthy patients. Patients with viral CNS infections had significantly raised beta 2 mu and lysozyme levels but normal lactoferrin levels, indicating a local activation of lymphocytes and monocytes but not of granulocytes. Patients with bacterial CNS infections had significantly raised levels of all three cell markers, but the increase of lysozyme and lactoferrin was relatively more pronounced than that of beta 2 mu, indicating that the inflammatory response to bacterial agents is dominated by monocytes and granulocytes. Patients with primary or secondary malignant brain tumors were characterized by a moderate increase of beta 2 mu and a considerable increase in both lysozyme and lactoferrin, i.e., the same protein pattern as observed in bacterial CNS infection. The lysozyme levels were moderately increased in half the patients with benign cerebral tumors while the levels of beta 2 mu and lactoferrin were normal, indicating that benign and malignant brain tumors induce different local inflammatory CNS reactions. Half the patients with pituitary gland adenoma had elevated beta 2 mu and lysozyme levels but normal lactoferrin levels, suggesting that immunological mechanisms are associated with the adenoma development. Patients with MS had moderately but significantly raised CSF levels of beta 2 mu and lysozyme and a third of them also had raised levels of lactoferrin, a protein pattern suggesting a low-active inflammatory process in CNS involving mononuclears and granulocytes. A similar protein pattern was found in Guillain-Barré syndrome. In cerebrosarcoidosis we noted considerably increased lysozyme and beta 2 mu but normal lactoferrin levels, consistent with the idea that the sarcoid granuloma mass is dominated by monocytic inflammatory cells. The data obtained indicate a clinical value of lactoferrin, lysozyme, and beta 2 mu as differential indices of inflammatory cell reactions taking place in various CNS processes.

Topics: Adult; Albumins; Bacterial Infections; beta 2-Microglobulin; Beta-Globulins; Central Nervous System Diseases; Cerebrospinal Fluid Proteins; Female; Humans; Inflammation; Lactoferrin; Lactoglobulins; Male; Muramidase; Virus Diseases

Topics: Adolescent; Adult; Aged; Animals; Bacterial Infections; Child; Child, Preschool; Dogs; Ear, Middle; Eustachian Tube; Food Hypersensitivity; Gases; Humans; Hypersensitivity; Immunoglobulin E; Infant; Lymph; Middle Aged; Mucus; Muramidase; Otitis Media; Otitis Media with Effusion; Perilymph

The behaviour of peripheral blood granulocyte pools, nitroblue tetrazolium reduction by granulocytes, migration of granulocytes out of skin windows, serum muramidase activity and bone marrow reserve of granulocytes during uncomplicated bronchopneumonia were studied. The time course of changes in these parameters during infection was established, and suggests maximal changes on day 2 of infection with gradual regression until 30 days after the disease onset, when they disappear.

Topics: Adult; Bacterial Infections; Bone Marrow; Bronchopneumonia; Granulocytes; Humans; Leukocyte Count; Male; Muramidase; Nitroblue Tetrazolium; Oxidation-Reduction; Skin Window Technique; Time Factors

The determination of lysozyme has been shown to be more relevant than assumed until now. It can be used as a marker in the therapy of acute and chronic urinary tract infections. The determination of lysozyme in cerebro spinal fluid and blood serum are helpful to differentiate between bacterial and aseptic meningitides or infections. Elevated fecal lysozyme excretion in adolescents are an indicator for a chronic inflammatory bowel disease. Control of fecal lysozyme excretion can be used as a marker for a relapse and to monitor therapeutic efficiency in patients with inflammatory bowel disease. A consistent high level of fecal lysozyme excretion in adults over the age of 40 is an indicator for possible colorectal tumors and warrants further thorough investigation.

Topics: Adolescent; Adult; Bacterial Infections; BCG Vaccine; Colonic Neoplasms; Crohn Disease; Diagnosis, Differential; Feces; Humans; Macrophages; Meningitis; Monocytes; Muramidase

Topics: Bacterial Infections; Humans; Immunoglobulin A, Secretory; Muramidase; Respiratory Tract Infections; Sputum

Topics: Bacterial Infections; Child; Colitis, Ulcerative; Crohn Disease; Diagnosis, Differential; Feces; Hepatitis A; Humans; Meningitis; Meningitis, Aseptic; Muramidase; Urinary Tract Infections; Virus Diseases

Topics: Adolescent; Adult; Aged; Bacterial Infections; Blood Bactericidal Activity; Complement System Proteins; Granulocytes; Humans; Immunoglobulins; Leukemia; Leukocyte Count; Middle Aged; Muramidase; Phagocytosis

The paper was aimed at an evaluation of nonspecific humoral resistance in CS2 chronically exposed workers. The studies covered 68 men of medium, 16 years, duration of employment in exposure and 20 controls. In all subjects the concentration of lysozyme and some ferrum economy parameters were determined. In the group of chronically CS2 exposed workers the serum lysozyme index was found to be statistically significantly decreased. In addition, in 14.7% of subjects, increased ferrum concentration and increased index of plasmatic transferin saturation with ferrum were found as well as statistically significant decrease in lysozyme concentration and index. The observed changes in the parameters concerned, contributing to the system of humoral nonspecific resistance may result in an increased infectious diseases incidence among the CS2 exposed workers.

Topics: Antibody Formation; Bacterial Infections; Carbon Disulfide; Humans; Iron; Male; Muramidase; Occupational Diseases; Time Factors; Transferrin

Topics: Animals; Bacterial Infections; Bacteriolysis; Bronchi; Female; Muramidase; Rats; Rats, Inbred Strains; Respiratory Tract Infections; Tissue Distribution

C.S.F. lactate- and lysozyme concentrations were determined in 74 children with bacterial and aseptic meningitis, combined with other laboratory findings (white-cell count, differential blood count, total protein, glucose). Lactate and lysozyme concentrations proved to be best for the differentiation between bacterial and aseptic meningitis.

Topics: Adolescent; Bacterial Infections; Blood Glucose; Blood Proteins; Child; Child, Preschool; Humans; Infant; Infant, Newborn; Lactates; Leukocyte Count; Meningitis; Muramidase

Topics: Bacterial Infections; Bacteriocins; Escherichia coli; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Intestinal Diseases; Lactobacillus; Muramidase

Topics: Adolescent; Bacterial Infections; Child; Child, Preschool; Female; Humans; Immunosuppressive Agents; Infant; Male; Muramidase; Virus Diseases

Cerebrospinal fluid (CSF) and serum lysozyme concentrations were determined in infants and children with and without acute infectious disease of the central nervous system. Serum lysozyme values from patients with bacterial and viral meningitis were found within the normal range. Lysozyme activity was absent or very low (below 0.5 microgram/ml) in normal CSF. High levels (4-12 microgram/ml) in patients with viral meningitis. A decrease of the lysozyme activity coincided with the clinical improvement of the bacterial meningitis. The lysozyme activity in CSF should be of significant value in detecting an inflammatory disease of the central nervous system.

Topics: Bacterial Infections; Child; Child, Preschool; Humans; Infant; Meningitis; Meningitis, Viral; Muramidase

Topics: Bacterial Infections; Humans; Muramidase; Skin; Skin Diseases; Skin Diseases, Infectious

The changes in intraneutrophilic and plasma concentrations of the three antibacterial proteins lysozyme, lactoferrin, and myeloperoxidase were studied sequentially during acute bacterial infection in nine patients. Intraneutrophilic concentrations of the three proteins were decreased by more than 50% during the 1st week of infection, followed by a slow increase over the following 2 weeks. Nadir values coincided with maximal toxic granulation of the neutrophils. The data suggest that neutrophilic granulocytes are deficient during early bacterial infection, possibly because of deficient synthesis of antibacterial proteins in the bone marrow, and that neutrophil toxic granulation is the visual counterpart of this defect. The plasma concentrations of the three proteins showed considerable differences: whereas plasma lysozyme did not show any sequential changes, plasma myeloperoxidase was high at the start of infection and quickly decreased towards normal values, and plasma lactoferrin, high in the first samples, showed a secondary peak 1 week after onset of disease, before normalization was seen. These differences may result from differences in the signals are specific for the individual antibacterial protein and not for the different types of neutrophil granules.

Topics: Adult; Aged; Bacterial Infections; Blood Bactericidal Activity; Humans; Lactoferrin; Lactoglobulins; Meningitis; Middle Aged; Muramidase; Neutrophils; Peroxidase; Peroxidases; Pneumococcal Infections; Time Factors

Topics: Animals; Bacterial Infections; Conjunctiva; Conjunctivitis; Guinea Pigs; Moraxella; Muramidase; Tears; Vitamin B 6 Deficiency

A new methodological approach to the study of the organism resistance to infection with the use of experimental animals with controlled microflora (germfree and other categories of gnotobiotic animals) is considered. Characteristics of the state of natural resistance of germfree animals, revealing considerable defects of cellular and humoral protection mechanisms, are given. Findings of experimental studies into inflammation, phagocytosis and other reactions of nonspecific resistance in gnotobiotic animals, disclosing complex mechanisms of formation of these reactions under the influence of microflora, are presented. The etiological and pathogenetic role of the microbial factor in the development of infectious diseases and in the formation of mechanisms of protective reactions at various levels of integration of the organism are discussed. Conclusions concerning prospects of the gnotobiological approach in investigating the role of the microbic factor in pathology are set forth.

Topics: Animals; Antibody Formation; Bacterial Infections; Burns; Cell Movement; Complement System Proteins; Germ-Free Life; Growth; Guinea Pigs; Immunity, Cellular; Infections; Inflammation; Intestines; Leukocytes; Mice; Muramidase; Phagocytosis; Properdin; Rats; Virus Diseases

Topics: Animals; Antigens; Bacterial Infections; Escherichia coli; Female; Immunity; Immunization; Male; Mercaptopurine; Mice; Muramidase

Infusion of cycloheximide i.v., an antibiotic known to inhibit synthesis of protein, at a rate of 0.2 mg/kg/hr, reliably caused lysis of fever in 15 chronically febrile patients with Hodgkin's disease who did not have detectable bacterial, fungal, or viral infection. Antipyretic effects were also seen in some patients with reticulum cell sarcoma, lymphosarcoma, acute leukemia, histiocytic medullary reticulosis, plasma cell myeloma, carcinoma of the lung, and carcinoma of the cervix. The drug failed to produce defervescence in four patients with normal granulocyte reserves, who were febrile due to bacterial infection. When infused at a rate of 0.2 mg/kg/hr, the drug apparently caused an acute alteration of protein metabolism in man in that plasma amino acid nitrogen rose acutely while plasma levels of muramidase and ribonuclease fell during the period of the infusion. The data suggest that continuing synthesis of protein may be involved in nonbacterial fever of neoplastic disease. Mammalian granulocytes and monocytes are known to elaborate a pyrogenic protein following appropriate stimulation; it is suggested that in some types of neoplastic disease, particularly Hodgkin's disease, tumor cells may produce and release a pyrogenic protein and that drug-induced inhibition of its synthesis is responsible for the observed lysis of fever.

Topics: Bacterial Infections; Cycloheximide; Female; Fever; Hodgkin Disease; Humans; Leukemia; Lung Neoplasms; Lymphatic Diseases; Lymphoma, Large B-Cell, Diffuse; Lymphoma, Non-Hodgkin; Multiple Myeloma; Muramidase; Neoplasm Proteins; Neoplasms; Nitrogen; Ribonucleases; Uterine Cervical Neoplasms

Long-term immunosuppressive therapy of mice with 6-mercaptopurine (6-MP) for 2 and/or 3 weeks results in partial lethality, decrease of total leukocyte count, of serum lysozyme level and in bacteremia. The adverse effect of 6-MP treatment could not be prevented by lysozyme administration; immunization with Escherichia coli O86 antigen further increased the lethality of 6-MP in mice. The results stress the potential danger of immunization with bacterial antigens during immunosuppressive therapy.

Topics: Animals; Antigens, Bacterial; Bacterial Infections; Blood; Body Weight; Enterobacteriaceae; Escherichia coli; Female; Immunization; Immunosuppressive Agents; Injections, Intraperitoneal; Leukocyte Count; Male; Mercaptopurine; Mice; Muramidase; Proteus

In this review the mechanisms whereby amniotic fluid serves to protect the fetus from microbial disease have considered. It appears from the data reviewed that the principal mode of antibacterial action of amniotic fluid is bacteriostasis. Thus, the host is able to cope with a small number of organisms introduced into the amniotic cavity; however when the amniotic fluid is grossly contaminated the host resistance capacity of the amniotic fluid may be overwhelmed. This may be understood best by the quantitative description of disease theroized by Theobald Smith (94). Smith suggested that disease was a function of the number of organisms with which a host is initially infected multiplied by the virulence of the organism. The effects of the number and virulence of the organism in producing disease is lessened by the host's resistance capacity. This concept of disease is summarized by the equation: Disease equals (number) (virulence)/resistance. Although these parameters do not possess numeric values, it is possible to see at least conceptually their interplay with respect to intrauterine infection. For example, the number of organisms reaching the amniotic fluid may be increased by various modes, namely maternal viremia or bacteremia; premature rupture of the fetal membranes, antenatal vaginal examination and possibly intrauterine fetal monitoring. While these circumstances may result in increased rate of infection, some reports conversely indicate that minimal bacterial contamination in the amniotic fluid is not an extraordinary occurrence and may not result in any maternal or fetal complication (73,74). The intrinsic host resistance capacity of the amniotic fluid likewise represents an important part of the Smith equation for disease. We have found that amniotic fluids may vary in antibacterial efficacy from almost no inhibitory activity to profound bactericidal activity (90). Obviously, the likelihood of the production of disease by an equivalent inoculum of a particular organism would be quite different depending upon the intrinsic inhibitory capacity of the amniotic fluid. The measurement of the inhibitory capacity of amniotic fluid holds some promise for enabling a physician to determine which patients may be at special risk of intrauterine infection.

Topics: Amnion; Amniotic Fluid; Animals; Bacteria; Bacterial Infections; Complement System Proteins; Culture Media; Female; Humans; Immunoglobulins; In Vitro Techniques; Muramidase; Peptides; Peroxidases; Pregnancy; Pregnancy Complications, Infectious; Steroids; Transferrin

Topics: Adult; Bacterial Infections; Biological Products; Complement System Proteins; Enterocolitis, Pseudomembranous; Female; Hepatitis A; Humans; Intestines; Leukocytes; Middle Aged; Muramidase; Prodigiosin; Sepsis; Staphylococcal Infections

Topics: Bacitracin; Bacterial Infections; Drug Combinations; Drug Resistance, Microbial; Humans; Laryngeal Diseases; Microbial Sensitivity Tests; Mouth Diseases; Muramidase; Papain; Pharyngeal Diseases

Topics: Agammaglobulinemia; Age Factors; Bacterial Infections; Bronchitis; Child, Preschool; Chronic Disease; Complement System Proteins; Humans; Immunoglobulin A; Immunoglobulin G; Infant; Muramidase; Virus Diseases

Topics: Bacterial Infections; Diabetes Mellitus; Hodgkin Disease; Humans; Leukemia; Leukemia, Monocytic, Acute; Leukemia, Myeloid; Leukocytes; Lymphoma, Large B-Cell, Diffuse; Muramidase

Topics: Acid Phosphatase; Animals; Bacterial Infections; Basement Membrane; Cell Membrane; Diptera; Endoplasmic Reticulum; Ferritins; Glycogen; Hemolymph; Histocytochemistry; Hydrolysis; Inclusion Bodies; Larva; Lysosomes; Methods; Microscopy, Electron; Microscopy, Phase-Contrast; Mitochondria; Muramidase; Pericardium; Peroxidases

Topics: Acid Phosphatase; Adult; Agranulocytosis; Alkaline Phosphatase; Bacterial Infections; Chediak-Higashi Syndrome; Chemotaxis; Female; Glucuronidase; Humans; Leukocytes; Lysosomes; Male; Muramidase; Peroxidases; Skin Window Technique; Staphylococcal Infections; Streptococcal Infections

Topics: Adolescent; Adult; Aged; Bacterial Infections; Burns; Candidiasis; Child; Child, Preschool; Female; Humans; Infant; Kidney Transplantation; Leukocytes; Male; Middle Aged; Muramidase; Neutrophils; Periodicity; Peroxidases; Phagocytes; Phagocytosis; Sepsis; Transplantation, Homologous; Wound Infection

Topics: Animals; Antibodies; Bacterial Infections; Cattle; Female; Mice; Milk; Muramidase; Opsonin Proteins; Salmonella Infections; Staphylococcal Infections

Topics: Administration, Oral; Anti-Infective Agents; Bacterial Infections; Case-Control Studies; Female; Histiocytes; Humans; Inflammation; Male; Muramidase; Phagocytosis; Skin Window Technique; Wound Healing

Topics: Bacterial Infections; Cytoplasm; Humans; Leukocytes; Macrophages; Muramidase