muramidase and Streptococcal-Infections

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

Dandelion flower is a well-known phytomedicine due to its therapeutic effects on dyspepsia, bile duct disorders, spleen and liver complaints, and inflammatory diseases. This study aimed to assess the effect of dietary dandelion flower extract (DFE) on skin mucosal and humoral immunity, immune-related gene expression, and disease resistance in rainbow trout. The fingerlings (N = 300, 20.1 ± 0.9 g) were randomly assigned to 15 tanks and fed with different levels of DEF including 0 (control), 1, 2, 3, and 4 g/kg for 56 days. At the end of the trial, the total leukocyte and lymphocyte counts were significantly enhanced in DFE-added groups compared to the control group. Complement components, immunoglobulin M, total protein, and lysozyme showed significantly higher values in the fish treated with dietary DFE at 3 g/kg than others (P < 0.05). The enzymatic activities of the skin mucus samples in the fish fed dietary levels of DFE were significantly higher than the control fish. Skin mucus protein was also improved significantly in 2 and 3 g/kg DFE compared to others. The transcription levels of interleukin-1β and interleukin-6 genes were up-regulated in the fish fed with 3 and 4 g/kg DFE. Interleukin-8 and lysozyme gene expression levels were elevated in 3 g/kg DFE group compared to the control group. Fish mortality after challenging with Streptococcus iniae was significantly reduced from 43.33% in the control group to 73.33% in 3 g/kg DFE group. This study confirmed the beneficial effects of DFE as an immunostimulant in rainbow trout diet and the recommended dose of DFE is 2.49-2.74 g/kg based on the polynomial regression models.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Dietary Supplements; Flowers; Immunization; Muramidase; Oncorhynchus mykiss; Plant Extracts; Streptococcal Infections; Streptococcus iniae; Taraxacum

Streptococcus agalactiae is one of the most important pathogens infecting tilapia worldwide and causes meningoencephalitis, septicemia and high mortalities with considerable losses. Various types of vaccines have been developed against S. agalactiae infection, such as inactivated vaccines, live attenuated vaccines and subunit vaccines. Bacterial ghosts (BGs) are nonliving, empty cell envelopes and have been reported as novel vaccine candidates. Therefore, the main aims of this study were to develop an S. agalactiae ghost vaccine (SAGV) and to evaluate the immune response and protective effect of SAGV against S. agalactiae with two novel adjuvants, Montanide™ ISA 763B VG and Montanide™ GEL02. Nile tilapia, mean weight 50 g, were divided into four groups as follows; 1) fish injected with PBS as control, 2) fish injected with the SAGV alone; 3) fish injected with the SAGV+Montanide™ ISA 763B VG; and 4) fish injected with SAGV+Montanide™ GEL02. Following vaccination, innate immunity parameters including serum lysozyme, myeloperoxidase, catalase, and bactericidal activity were all significantly enhanced. Moreover, specific serum IgM antibodies were induced and reached their highest level 2-8 weeks post vaccination. Importantly, the relative percent survival of tilapia vaccinated against the SAGV formulated with both adjuvants was 80-93%. Furthermore, the transcription of immune-related genes (IgM, TCRβ, IL-1β, IL-8 and TNFα) were up-regulated in tilapia after vaccination, indicating that both cellular and humoral immune responses were induced by these adjuvanted vaccines. In summary, Montanide™ ISA 763B VG and Montanide™ GEL02 can enhance immunoprotection induced by the SAGV vaccine against streptococcosis, demonstrating that both have value as potential adjuvants of fish vaccines.

Topics: Adjuvants, Immunologic; Animals; Antibodies, Bacterial; Catalase; Cichlids; Fish Diseases; Fish Proteins; Liver; Mannitol; Muramidase; Peroxidase; Spleen; Streptococcal Infections; Streptococcal Vaccines; Streptococcus agalactiae

An eight-week investigation was conducted to access the potential impact of dietary watermelon rind powder (WMRP) and L. plantarum CR1T5 (LP) administered individually or in combination on immunity, disease resistance, and growth rate of Nile tilapia fingerlings cultured in a biofloc system. Three hundred twenty fish (average weight 16.57 ± 0.14 g) were distributed into 16 tanks at a rate of 20 fish per tank. The fish were fed different diets: Diet 1 (0 g kg

Topics: Animal Feed; Animals; Aquaculture; Cichlids; Citrullus; Diet; Disease Resistance; Lactobacillus plantarum; Leukocyte Count; Micrococcus; Mucus; Muramidase; Peroxidase; Phagocytosis; Plant Preparations; Powders; Prebiotics; Respiratory Burst; Skin; Streptococcal Infections; Streptococcus agalactiae; Synbiotics

The association of vaccines with immunostimulants such as β-glucan, promote the production of cytokines, competent immune cells and antibodies. However, differences between β-glucan types and trials make it difficult to understand β-glucan's mechanism of action. In this study, three trials were carried out with control and fish fed β-glucan, the first trial occurred at 15 days; the second trial occurred at 30 days when we associated β-glucan and vaccine; and the third trial occurred at 15 days post-challenge with Streptococcus agalactiae in tilapia (O. niloticus) in order to investigate immune-related gene expression in the head kidney and spleen using real-time qPCR. We found increases in HSP70, IL-6, IL-1β, TNF-α, IL-10, Lys and C3 predominantly in the head kidney, except for IgM expression, which prevailed in the spleen, under vaccinated + β-glucan action. This demonstrates the trade-off presented by the head kidney and spleen after immunostimulation in order to produce acquired immunity, as well as an increase in HSP70 expression in vaccinated + β-glucan fish. The results suggest that β-glucan stimulates the immune response through damage-associated molecular patterns (DAMPs) recognition. Therefore, these dynamics of the immune response promote a more robust defense against disease.

Topics: Adaptive Immunity; Adjuvants, Immunologic; Animals; beta-Glucans; Cichlids; Cytokines; Fish Diseases; Fish Proteins; Gene Expression; Head Kidney; HSP70 Heat-Shock Proteins; Muramidase; Signal Transduction; Spleen; Streptococcal Infections; Streptococcal Vaccines; Streptococcus agalactiae

A feeding study was conducted to determine the effect of dietary nucleotides (NT) on growth performance, immune responses and resistance of rainbow trout fingerlings to Streptococcus iniae. A basal diet supplemented with 0 (control), 0.5, 1, 1.5 and 2 g NT kg(-1) to formulate five experimental diets. Each diet was randomly allocated to triplicate groups of fish with initial average weight of approximately 23 g. After 8 weeks of feeding trial, fish fed diets with 1.5-2 g NT kg(-1) had the highest final weight and SGR, followed by groups fed the diets with 0.5-1 g NT kg(-1), and lowest in fish fed the NT-free control diet. The feed conversion ratio (FCR) was better when the fish were fed diet with 2 g NT kg(-1). The ACH(50) level and lysozyme activity in serum were found to be significantly (P < 0.05) greater in fish fed nucleotides at 1.5-2 g kg(-1). The fish fed with 2 g NT kg(-1) had higher IgM level. The challenge experiment showed that relative percent survival (RPS) increased significantly (P < 0.05) with increasing levels of nucleotides from 0.5 to 2 g kg(-1) and was lowest in the control group. We therefore recommend dietary nucleotide administration at 1.5-2 g kg(-1) to promote growth and enhance immunity and resistance against S. iniae.

Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Diet; Dietary Supplements; Dose-Response Relationship, Drug; Fish Diseases; Muramidase; Nucleotides; Oncorhynchus mykiss; Streptococcal Infections

Streptococcus mutans, a major pathogen of dental caries, is also known as a causative agent of cardiovascular disease. A 120 kDa collagen-binding protein (Cnm) of S. mutans is an important contributor to the pathogenicity of cardiovascular disease. Although dead bacteria have been detected in cardiovascular specimens by molecular biological methods, the pathogenicity of the bacteria remains unknown. Here, we analyzed the pathogenicity of killed S. mutans by focusing on collagen-binding ability and the effects on silkworms. In live S. mutans, Cnm-positive S. mutans had high collagen-binding activity, while Cnm-negative S. mutans had no such activity. After treatment with killed Cnm-positive S. mutans, amoxicillin-treated bacteria still had collagen-binding ability, while lysozyme-treated bacteria lost this ability. When live and amoxicillin-treated S. mutans strains were administered to silkworms, the survival rates of the silkworms were reduced; this reduction was more pronounced in Cnm-positive S. mutans infection than in Cnm-negative S. mutans infection. However, the administration of any of the lysozyme-treated bacteria did not reduce the survival rate of the silkworms. These results suggest that amoxicillin-killed Cnm-positive S. mutans strains maintain collagen-binding properties and pathogenicity in the silkworm model, and are possibly associated with pathogenicity in cardiovascular diseases.

Topics: Adhesins, Bacterial; Amoxicillin; Animals; Bombyx; Cardiovascular Diseases; Carrier Proteins; Collagen; Dental Caries; Disease Models, Animal; Humans; Muramidase; Saliva; Streptococcal Infections; Streptococcus mutans; Virulence

This study evaluates the effects of longan seed powder (LS) on the growth performance, immunological response, and immune-antioxidant related gene expression of Nile tilapia (Oreochromis niloticus). Three hundred fish (13.82 ± 0.06 g) were divided into five experiments and fed 5 diets, including the basal diet (control without LS) and basal diet containing 10 (LS10), 20 (LS20), 40 (LS40), and 80 (LS80) g kg

Topics: Animal Feed; Animals; Antioxidants; Aquaculture; Cichlids; Diet; Dietary Supplements; Disease Resistance; Fish Diseases; Gene Expression; Muramidase; Peroxidase; Powders; Sapindaceae; Seeds; Streptococcal Infections

Streptococcus gordonii is an etiological bacterial agent of infective endocarditis. Although the pathogenesis mechanisms are not well understood, the interaction between streptococci and phagocytes is considered important for the development of infective endocarditis. Previous studies show that some S. gordonii strains, including DL1, survive in polymorphonuclear leukocytes (PMNs), whereas other strains such as SK12 are sensitive to PMN-dependent killing. In this study, we assessed the differences between the sensitivity of S. gordonii DL1 and S. gordonii SK12 to PMN-dependent killing. S. gordonii DL1 showed a higher survival when treated with PMNs than SK12. Both S. gordonii DL1 and S. gordonii SK12 showed high resistance to low pH condition. Compared to S. gordonii SK12, S. gordonii DL1 was sensitive to hydrogen peroxide. However, the resistance of S. gordonii DL1 to the tested bactericidal agents, especially lysozyme, was higher than that of SK12. Furthermore, we performed a bactericidal assay by treating a mixture of S. gordonii DL1 and SK12 with PMNs. S. gordonii DL1 did not enhance the survival of S. gordonii SK12 exposed to PMNs. These results indicated that S. gordonii DL1 is resistant to bactericidal agents that degrade bacteria in phagolysosomes. In addition, there was no secretory factor involved in the resistance to bactericidal agents. The findings of this study may help develop treatments for infective endocarditis caused by S. gordonii.

Topics: Endocarditis, Bacterial; Humans; Muramidase; Neutrophils; Streptococcal Infections; Streptococcus gordonii

Medicated feed is a common strategy to control the occurrence of Streptococcus suis disease in swine production, but feed additives may constitute an alternative to metaphylaxis. In a farm with post-weaning S. suis disease, the following additives were tested: lysozyme (Lys), medium chain fatty acids plus lysozyme (FA + Lys), FA plus a natural anti-inflammatory (FA + antiinf) and amoxicillin (Amox). During the course of the study, FA + antiinf and Amox groups showed lower prevalence of clinical signs compatible with S. suis disease than the rest of the groups. Piglets from the FA + antiinf group showed high diversity and richness in their nasal and faecal microbiota. Diet supplements did not have major effects on the faecal microbiota, where the genus Mitsuokella was the only differentially present in the FA + Lys group. In the nasal microbiota, piglets from FA + antiinf presented higher differential abundance of a sequence variant from Ruminococcaceae and lower abundance of an unclassified genus from Weeksellaceae. In general, we detected more significant changes in the nasal than in the feacal microbiota, and found that parity of the dams affected the microbiota composition of their offspring, with piglets born to gilts exhibiting lower richness and diversity. Our results suggest that additives could be useful to control post-weaning disease when removing antimicrobials in farms.

Topics: Agriculture; Amoxicillin; Animal Feed; Animals; Anti-Infective Agents; Dietary Supplements; DNA, Bacterial; Fatty Acids; Feces; Female; Food Additives; Microbiota; Muramidase; Nasal Mucosa; Parity; Polymerase Chain Reaction; Pregnancy; Streptococcal Infections; Streptococcus suis; Swine; Treatment Outcome; Weaning

Yellow catfish (Pelteobagrus fulvidraco) is an important economic cultured fish in China. Here we report antioxidative activity and immune regulation in head kidney using a central composite design based on water temperature (20-34 °C) and dietary lipid (2-17%). Response values were optimized using response surface methodology to maximize the immune response and relieve oxidative stress. The experiment was conducted under laboratory conditions and lasted for seven weeks. The results showed that the linear effects of lipid level on superoxide dismutase (SOD, and lysozyme (LYZ) activity, and malondialdehyde (MDA) content in head kidney, respiratory burst activity (RBA) of head kidney macrophages, and cumulative mortality of fish infected by Streptococcus iniae (S. iniae) were significant (P < 0.05). Similarly, the linear effects of water temperature on SOD activity, MDA content, and cumulative mortality were significant (P < 0.05). In addition, the quadratic effects of water temperature and lipid level on all experimental response values were significant (P < 0.05), and no interactive effect was found between water temperature and lipid level (P > 0.05). High water temperature and high lipid diet significantly reduced the antioxidative activity and immune response in head kidney, and increased MDA content, which caused increased mortality of the S. iniae-infected fish. The adjusted R

Topics: Animals; Antioxidants; Aquaculture; Catfishes; Fish Diseases; Fish Proteins; Head Kidney; Immunity, Innate; Lipid Metabolism; Macrophages; Malondialdehyde; Models, Statistical; Muramidase; Streptococcal Infections; Streptococcus iniae; Superoxide Dismutase; Temperature

Streptococcus suis is a highly invasive pathogen that can cause sepsis and meningitis in pigs and humans. However, we have limited understanding of the mechanisms S. suis uses to evade innate immunity. To investigate the involvement of the two-component signal transduction system of S. suis in host immune defense, we examined the expression of 15 response regulators of S. suis following stimulation with polymorphonuclear leukocytes (PMNs). We found that several response regulators were significantly up-regulated including vraR. Thus, we constructed an isogenic deletion mutant of vraSR genes in S. suis and demonstrated VraSR promotes both bacterial survival in human blood and resistance to human PMN-mediated killing. The VraSR mutant was more susceptible to phagocytosis by human PMNs and had greater sensitivity to oxidant and lysozyme than wild-type S. suis. Furthermore, in vitro findings and in vivo evidence from a mouse infection model together strongly demonstrate that ΔvraSR had greatly attenuated virulence compared with wild-type S. suis. Collectively, our data reveal that VraSR is a critical regulatory system that contributes to the survival of S. suis and its ability to defend against host innate immunity.

Topics: Animals; Bacterial Proteins; Blood Bactericidal Activity; Cells, Cultured; Disease Models, Animal; Gene Deletion; Humans; Immune Evasion; Immunity, Innate; Mice; Microbial Viability; Muramidase; Neutrophils; Oxidants; Phagocytosis; Signal Transduction; Streptococcal Infections; Streptococcus suis; Virulence; Virulence Factors

The present study investigates the effects of orange peels derived pectin (OPDP) on skin mucus and serum immune parameters, disease resistance and growth performance of O. niloticus cultured under indoor biofloc system. Six hundred Nile tilapia (average weight 9.09 ± 0.05 g) were distributed into 15 fiber tanks (300 L per tank) assigned to five treatments repeated in triplicate. Fish were fed experimental diets contain different levels OPDP as follows: 0 (control in clear water), 0 (control in biofloc system), 5, 10, and 20 g kg

Topics: Animals; Cichlids; Citrus sinensis; Complement Pathway, Alternative; Disease Resistance; Fish Diseases; Fruit; Immunity, Innate; Mucus; Muramidase; Pectins; Peroxidases; Phagocytosis; Respiratory Burst; Skin; Streptococcal Infections; Streptococcus agalactiae

Streptococcus dysgalactiae is considered a causative agent of severe infection and economic loss for the cobia industry in Taiwan. In this study, protective antigens of this pathogenic bacterium were identified and screened in cobia (Rachycentron canadum). Outer surface proteins (OMPs) of this pathogen were extracted using mutanolysin digestion. Immunogenic targets were detected by western blot and then subjected to peptide sequencing using NanoLC-MS/MS. Two surface proteins, namely phosphoenolpyruvate protein phosphotransferase (PtsA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), showed strong reactions with cobia antisera against S. dysgalactiae. Recombinant proteins were produced in Escherichia coli cells and their protective efficacies were investigated in cobia. Fish immunised with recombinant proteins, rPtsA + ISA (ISA 763 AVG) and rGAPDH + ISA, elicited higher levels of specific antibody responses against the recombinant proteins and had high levels of lysozyme activity. Notably, vaccinated fish were protected from lethal challenge with relative percentage of survival (RPS) values for rPtsA + ISA and rGAPDH + ISA groups being 91.67% and 83.33%, while 0% RPS value was found in both ISA injected and control groups. The results presented in the study demonstrate that the GAPDH and PtsA are promising vaccine candidates for preventing S. dysgalactiae disease in cobia.

Topics: Animals; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Proteins; Cytokines; Fish Diseases; Kidney; Muramidase; Perciformes; Phosphoenolpyruvate Sugar Phosphotransferase System; Phosphoric Monoester Hydrolases; Phosphotransferases (Nitrogenous Group Acceptor); RNA, Messenger; Streptococcal Infections; Streptococcus; Vaccination

Topics: Animals; Bacterial Proteins; Humans; Muramidase; Streptococcal Infections; Streptococcus suis; Swine Diseases; Virulence

The marbled spinefoot rabbitfish (Siganus rivulatus) is an economically valuable fish species that has potential for commercial production in aquaculture. To overcome challenges in its sustainable production, a formulated diet is required for imparting health and robustness. This study evaluates the effect of dietary supplementation with arachidonic acid (ARA; 20:4n-6) on growth, survival, immune function and fatty acid composition of red blood cells (RBCs) in rabbitfish. We conducted two feeding trials using juvenile fish (to evaluate growth and survival) and adults (to evaluate immune function and fatty acid incorporation). Fish were fed diets supplemented with three different levels of ARA (in % of total fatty acids): 0.6 (unsupplemented control), 2.6 (moderate) and 4.7 (high). The fish fed with moderate ARA levels exhibited improved (p < 0.05) growth over the control and the high ARA level groups. During an outbreak of Streptococcus iniae, fish fed with moderate ARA survived significantly (p < 0.05) better (89%) than the control and the high ARA groups (59% and 48%, respectively). Moderate ARA supplementation resulted in elevated lysozyme and complement levels in the plasma of rabbitfish. A significant increase in the total serum immunoglobulin levels was observed in both the medium and the high ARA level groups; however, a decrease in antiprotease activity was recorded in the supplemented groups as compared to the control. Fatty acid analysis in fish red blood cells revealed a significant (p < 0.05) increase in the proportion of ARA of total fatty acids in the groups fed with the medium and the high ARA level diets (9.5% and 11.2%, respectively, compared to 7.1% in the control). Concomitantly, there was a decrease in the proportion of eicosapentaenoic acid (EPA; 20:5n-3), dihomo-γ linolenic acid (DGLA; 20:3n-6) and several 18-carbon unsaturated fatty acids in these groups. In conclusion, ARA in rabbitfish feeds improved growth, survival as well as innate and acquired humoral immune functions. Thus ARA supplementation in the diet of this species could be a valuable step towards establishing the commercial culture of rabbitfish.

Topics: Animal Feed; Animals; Arachidonic Acid; Diet; Dietary Supplements; Erythrocytes; Fatty Acids; Fish Diseases; Fish Proteins; Immunity, Innate; Immunoglobulins; Muramidase; Perciformes; Streptococcal Infections; Streptococcus iniae

The effects of oral vaccination by two immune routes (gavage and mixed fodder administration) using a recombinant DNA vaccine SL7207-pVAX1-sip against Streptococcus agalactiae were assessed. SL7207-pVAX1-sip significantly enhanced various innate immune responses of tilapia, such as total serum protein, superoxide dismutase activity, lysozyme activity, complement C3 concentration in serum, serum antibacterial activity, and interleukin 1β and tumor necrosis factor-α. Vaccinated fish had higher relative percent survival values (57% and 63% for gavage group and mix fodder administration, respectively) at 10 weeks after S. agalactiae infection. When administered mixed fodder, the DNA vaccine SL7207-pVAX1-sip against S. agalactiae may produce more effective protection. These findings can promote the application and development of DNA vaccines in aquaculture.

Topics: Administration, Oral; Animals; Bacterial Vaccines; Complement C3; Drug Administration Routes; Fish Diseases; Fish Proteins; Immunity, Innate; Interleukin-1beta; Muramidase; Streptococcal Infections; Streptococcus agalactiae; Superoxide Dismutase; Tilapia; Tumor Necrosis Factor-alpha; Up-Regulation; Vaccination; Vaccines, DNA

Olive flounder (Paralichthys olivaceus), also known as the Japanese flounder in Japan, is one of the most important commercial marine finfish species cultured in Korea and Japan. The purpose of this study was to evaluate how a species of brown algae (Ecklonia cava, E. cava) affects the growth rate of olive flounder and its immune response to pathogenic bacteria. First, the experimental fish were divided into four groups: the control group was fed the diet containing only 1.0% Lactobacillus plantarum (L. plantarum), group I was fed 1.0% L. plantarum and 1.0% E. cava (EC), group II was fed 1.0% L. plantarum and 0.1% ethanol extract of EC (EE), and group III was fed 1.0% L. plantarum and 0.5% EE. The diets fed to the fish twice a day for 16 weeks. The results indicated that supplementation with 1.0% EC and 0.1% EE improved the growth and body weight of olive flounder, and decreased its mortality. This diet, however, did not significantly affect the biochemical profiles of the experimental flounder. The supplementation of 1.0% EC also enhanced the innate immune response of the fish, as evidenced by the high respiratory burst, and increased serum lysozyme and myeloperoxidase activity. The addition of 1.0% EC and either 0.1% or 0.5% EE also decreased the accumulative mortality of olive flounder infected by pathogenic bacteria (Edwardsiella tarda, Streptococcus iniae, and Vibrio harveyi). Overall, these results suggest that E. cava can act as a prebiotic by improving the innate immune response in fish infected with pathogenic bacteria as increased the growth of the probiotic.

Topics: Animals; Body Weight; Edwardsiella tarda; Enterobacteriaceae Infections; Fish Diseases; Flounder; Lactobacillus plantarum; Muramidase; Peroxidase; Phaeophyceae; Prebiotics; Respiratory Burst; Streptococcal Infections; Streptococcus iniae; Vibrio; Vibrio Infections

The mucosal surfaces constitute the first line of host defense against infection, and also serve as the dynamic interfaces that simultaneously mediate a diverse array of critical physiological processes, while in constantly contact with a wide range of pathogens. The lysozymes are considered as key components for innate immune response to pathogen infection with their strong antibacterial activities. But their activities in mucosal immune responses were always overlooked, especially for g-type lysozymes, whose expression patterns in mucosal tissues following bacterial challenge are still limited. Towards to this end, here, we characterized the g-type lysozymes, Lyg1 and Lyg2 in turbot, and determined their expression patterns in mucosal barriers following different bacterial infection. The phylogenetic analysis revealed the turbot g-type lysozyme genes showed the closest relationship to Cynoglossus semilaevis. The two lysozyme genes showed different expression patterns following challenge. Lyg2 was significantly up-regulated in mucosal tissues following Vibrio anguillarum and Streptococcus iniae challenge, while Lyg1 showed a general trend of down-regulation. The significant mucosal expression signatures of g-type lysozyme genes indicated their key roles to prevent pathogen attachment and entry in the first line of host defense system. Further functional studies should be carried out to better characterize the availability of utilization of g-type lysozyme to increase the disease resistance in the mucosal surfaces and facilitate the disease resistant breeding selection.

Topics: Amino Acid Sequence; Animals; Fish Diseases; Fish Proteins; Flatfishes; Gene Expression Profiling; Gene Expression Regulation, Enzymologic; Immunity, Mucosal; Muramidase; Phylogeny; Sequence Alignment; Streptococcal Infections; Streptococcus iniae; Vibrio; Vibrio Infections

Lysozymes are a family of enzymes that catalyze the hydrolysis of bacterial cell wall, acting as antimicrobial effectors of the innate immune system. In the present study, an ortholog of goose-type lysozyme (ShLysG) from the big-belly seahorse (Hippocampus abdominalis) was identified and characterized structurally and functionally. The full-length cDNA sequence (1213 bp) of ShLysG is comprised of an open reading frame made up of 552 bp, encoding a polypeptide of 184 amino acid (aa) with a predicted molecular mass of 20 kDa. In silico analysis of ShLysG revealed the absence of signal peptide and the presence of a characteristic bacterial soluble lytic transglycosylase (SLT) domain bearing three catalytic residues (Glu

Topics: Amino Acid Sequence; Animals; Cloning, Molecular; DNA, Complementary; Edwardsiella tarda; Enterobacteriaceae Infections; Fish Diseases; Fish Proteins; Lipopolysaccharides; Muramidase; Pathogen-Associated Molecular Pattern Molecules; Phylogeny; Poly I-C; Recombinant Proteins; RNA, Messenger; Sequence Alignment; Smegmamorpha; Streptococcal Infections; Streptococcus iniae

Oreochromis niloticus bred in net cages were supplemented with cell wall of Saccharomyces cerevisiae (Sc) (0.3%) or chromium carbochelate (Cr) (18 mg/kg of feed) or in association (Sc + Cr), for 90 days. After this period, acute inflammation was induced in the swim bladder by inoculation of 3 × 10(8) CFU of inactivated Streptococcus agalactiae, and another group received 0.65% saline solution (control). Twelve, 24, and 48 h after stimulation, the inflammation was evaluated through total and differential counting of accumulated cells, and through leukocyte respiratory burst in the blood, cortisolemia, glycemia and serum lysozyme concentration. The results showed that there were greater total numbers of cells in the exudate of fish inoculated with inactivated bacterium than in those injected with saline solution, with predominance of lymphocytes, thrombocytes, macrophages and granulocytes. Tilapia supplemented with Cr presented increased total numbers of cells with significant accumulation of lymphocytes and reductions in cortisolemia and glycemia, but the different treatments did not have any influence on leukocyte respiratory burst or serum lysozyme concentration. Tilapia supplemented with Sc and the Cr + Sc association did not present significant changes to the variables evaluated, despite higher accumulation of lymphocytes in the inflammatory exudate from fish treated with Sc. The results indicate that tilapia bred in net cages and supplemented with Cr presented higher total accumulation of cells at the inflammatory focus, thus indicating an increase in the inflammatory response induced by the bacterium, probably due to the reduction in cortisolemia and higher glucose consumption. Thus, supplementation with Cr had beneficial action, which facilitated development of acute inflammation induced by the bacterium, but did not affect neither leukocyte respiratory burst in the blood nor serum lysozyme concentration.

Topics: Air Sacs; Animals; Blood Glucose; Chromium; Cichlids; Fish Diseases; Hydrocortisone; Muramidase; Probiotics; Random Allocation; Respiratory Burst; Respiratory Tract Infections; Saccharomyces cerevisiae; Streptococcal Infections; Streptococcus agalactiae

Streptococcus parauberis causing systemic infections has been recognized as a major bacterial disease in olive flounder Paralichthys olivaceus in South Korea. Although an emerging outbreak of S. parauberis has affected heavily farmed fish species starry flounder Platichthys stellatus, no study of the innate immune responses and pathogenic mechanisms in starry flounder is available. In the present study, starry flounder were intraperitoneally challenged with four S. parauberis strains to investigate changes in innate immune responses. Significant increases in serum lysozyme activities, superoxide production of kidney leucocytes, and serum superoxide dismutase activities were observed following experimental injection of S. parauberis. All these data suggested that the innate immune parameters were highly modulated during the S. parauberis infection process to render protection to the starry flounder. However, S. parauberis also exhibited the mechanisms to complete disease establishment by avoiding host immune responses. S. parauberis could survive and proliferate in the mucus, serum and kidney leucocytes of starry flounder. In particular, the strain isolated from the starry flounder showed the higher survival ability than other originated strains in the tested host fish.

Topics: Animals; Fish Diseases; Flounder; Immunity, Innate; Injections, Intraperitoneal; Kidney; Leukocytes; Muramidase; Nitroblue Tetrazolium; Organ Specificity; Streptococcal Infections; Streptococcus; Superoxide Dismutase

Topics: Animals; China; Cichlids; Fish Diseases; Immunity, Innate; Muramidase; Nitroblue Tetrazolium; Phagocytosis; Species Specificity; Streptococcal Infections; Streptococcus agalactiae

This study was investigated to examine the effects of dietary inosine monophosphate (IMP) supplementation on growth performance, feed utilization, innate immunity, hematological parameters and disease resistance of juvenile olive flounder. Five experimental diets were formulated to contain IMP at levels of 0, 0.1, 0.2, 0.4 and 1.0%. All diets were maintained isonitrogenous (48% crude protein) and isocaloric (20.7 MJ/kg diet). Triplicate groups of olive flounder (initial body weight, 7.5 ± 0.02 g) were fed one of the experimental diets to apparent satiation (twice a day) for 14 weeks. Final body weight of fish fed 0.1-0.2% IMP were significantly higher than that of fish fed the 1.0% IMP. Groups of fish fed 0.2 or 0.4% IMP diet had significantly higher myeloperoxidase and lysozyme activities than fish fed the control diet. However, nitro-blue-tetrazolium and superoxide dismutase activities were not significantly different among all treatments. In the challenge test against Streptococcus iniae, cumulative mortality of fish fed IMP supplemented diets was significantly lower (15%, 4%, 4% and 9% for 0.1%, 0.2%, 0.4% and 1.0% IMP, respectively) than that of fish fed the control group (87%). The results suggest that IMP supplementation of 0.46-1.84 g into a kg of fish meal based diet (0.1-0.4% IMP product) can enhance innate immunity and disease resistance of olive flounder.

Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Aquaculture; Blood Chemical Analysis; Diet; Dietary Supplements; Disease Resistance; Dose-Response Relationship, Drug; Fish Diseases; Flounder; Hematocrit; Immunity, Innate; Inosine Monophosphate; Muramidase; Random Allocation; Respiratory Burst; Streptococcal Infections; Streptococcus; Superoxide Dismutase

The effect of diets containing sodium alginate at 0, 0.5, 1.0, and 2.0 g kg⁻¹ following challenge with Streptococcus iniae in kelp grouper Epinephelus bruneus were assessed with reference to survival rate and innate immune parameters such as alternative complement, lysozyme, natural haemagglutination, respiratory burst, superoxide dismutase, and phagocytic activities on week 1, 2, and 4. Fish fed with sodium alginate containing diet at 1.0 and 2.0 g kg⁻¹ after being challenged with S. iniae had higher survival rates of 75% and 60%, respectively than those fed with control diet (0 g kg⁻¹). With any enriched diet the percentage of macrophages significantly decreased from week 1-4, while the percentage of neutrophils and lymphocytes significantly increased. The alternate complement activity, natural haemagglutination, and phagocytic activities of infected fish fed with sodium alginate containing diet at 1.0 g kg⁻¹ on week 2 and 1.0 and 2.0 g kg⁻¹ diets on week 4 were significantly higher when compared to the control. The lysozyme, respiratory bursts, and superoxide dismutase activities of fish fed with enriched diets at 1.0 and 2.0 g kg⁻¹ were significantly increased on week 2 and 4. We therefore recommend that at 1.0 or 2.0 g kg⁻¹ dietary administration of sodium alginate can enhance innate immunity and disease resistance in kelp grouper against S. iniae.

Topics: Alginates; Animals; Complement Pathway, Alternative; Diet; Fish Diseases; Glucuronic Acid; Hemagglutination; Hexuronic Acids; Immune System; Immunologic Factors; Leukocytes; Muramidase; Phagocytosis; Respiratory Burst; Streptococcal Infections; Streptococcus; Superoxide Dismutase

The present study was reported the effect of probiotics and herbals mixture supplementation diet on growth, blood constituents, and nonspecific immune response in olive flounder Paralichthys olivaceus against Streptococcus parauberis on weeks 1, 2, 4, 6, 8, 10, and 12 after injected intraperitoneally (i.p.) with 50 μl of PBS (phosphate buffer saline) containing S. parauberis (2.1 × 10⁷ CFU ml⁻¹). The initial weight did not significantly increased in supplementation diet group from 1 to 4 weeks, whereas it was significantly increased from weeks 6 to 12 as compared to fish fed without supplementation diet. The serum aspartate aminotransferase (SGOT) and alanine aminotransferase (SGPT) activities significantly increased from weeks 4 to 12 in infected fish fed with supplementation diet compared to fish fed without supplementation diet. However, the total protein (TP) and glucose (GLU) levels were significantly increased in infected fish fed with supplementation diet after 6 weeks. The phagocytic, respiratory burst, complement, and lysozyme activities significantly enhanced in infected fish fed with supplementation diet from weeks 4 to 12 as compared to fish fed without supplementation diet. These results suggested that different probiotics and herbals mixture supplementation diet enhanced the growth, blood biochemical constituents, and nonspecific immunity in olive flounder against S. parauberis.

Topics: Alanine Transaminase; Animal Feed; Animals; Aspartate Aminotransferases; Bacillus subtilis; Complement System Proteins; Diet; Dietary Supplements; Eleutherococcus; Fish Diseases; Flounder; Glycyrrhiza uralensis; Immunity, Innate; Lactobacillus; Muramidase; Panax; Phagocytosis; Plant Extracts; Probiotics; Respiratory Burst; Saccharomyces; Streptococcal Infections; Streptococcus

The aquatic zoonotic pathogen Streptococcus iniae represents a threat to the worldwide aquaculture industry and poses a risk to humans who handle raw fish. Because little is known about the mechanisms of S. iniae pathogenesis or virulence factors, we established a high-throughput system combining whole-genome pyrosequencing and transposon mutagenesis that allowed us to identify virulence proteins, including Pdi, the polysaccharide deacetylase of S. iniae, that we describe here. Using bioinformatics tools, we identified a highly conserved signature motif in Pdi that is also conserved in the peptidoglycan deacetylase PgdA protein family. A Deltapdi mutant was attenuated for virulence in the hybrid striped bass model and for survival in whole fish blood. Moreover, Pdi was found to promote bacterial resistance to lysozyme killing and the ability to adhere to and invade epithelial cells. On the other hand, there was no difference in the autolytic potential, resistance to oxidative killing or resistance to cationic antimicrobial peptides between S. iniae wild-type and Deltapdi. In conclusion, we have demonstrated that pdi is involved in S. iniae adherence and invasion, lysozyme resistance and survival in fish blood, and have shown that pdi plays a role in the pathogenesis of S. iniae. Identification of Pdi and other S. iniae virulence proteins is a necessary initial step towards the development of appropriate preventive and therapeutic measures against diseases and economic losses caused by this pathogen.

Topics: Amidohydrolases; Amino Acid Sequence; Animals; Bacterial Adhesion; Bacterial Proteins; Bacteriolysis; Bass; Blood Bactericidal Activity; Cell Line; DNA Transposable Elements; Epithelial Cells; Fish Diseases; Gene Targeting; Genes, Bacterial; Genome, Bacterial; Molecular Sequence Data; Muramidase; Mutagenesis; Reactive Oxygen Species; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Streptococcal Infections; Streptococcus; Virulence; Virulence Factors

We report the growth, innate immune response, and disease resistance in olive flounder (Paralichthys olivaceus) challenged with Streptococcus iniae after feeding with diet enriched with Zooshikella sp. strain JE-34 three different concentration i.e. Low (3.4 x 10(4), n = 50), medium (3.5 x 10(6), n = 50), and high (3.4 x 10(8), n = 50) cfu ml(-1) supplemented diets, the changes were monitored on weeks 1, 2, 4, 8, 12, and 16. With all diets the innate immune parameters, such as superoxide anion production, phagocytic and lysozyme activity were not enhanced on week 1 and 4. On the other hand, all tested immune parameters in the treated groups significantly enhanced after 8th week; the weight gain significantly increased after 4th week in fish fed with enriched diets. The mortality in olive flounder after administration with high concentration diet showed 25%. With low and medium enriched diets the mortality was 40% and 35%, respectively. In the infected untreated group mortality was 85% while there was no mortality in the control group. The results suggested that Zooshikella sp. strain JE-34 enriched diets could be used to enhance the innate immune response and disease resistance of P. olivaceus against S. iniae.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Blood Glucose; Cell Survival; Cholesterol; Fish Diseases; Flounder; Gammaproteobacteria; Hemoglobins; Leukocytes, Mononuclear; Muramidase; Phagocytosis; Phosphorus; Probiotics; Streptococcal Infections; Streptococcus; Triglycerides

Bacterial virulence could be altered by the antimicrobial agents of the host. Our aim was to identify the damage and survival of Streptococcus sanguinis induced by lysozymes in vitro and to analyse the potential of oral microorganisms to shirk host defences, which cause infective endocarditis. S. sanguinis ATCC 10556 received lysozyme at concentrations of 12.5, 25, 50 and 100 microg/ml. Cells were examined by electron microscopy. The survival was assessed by colony counting and construction of a growth curve. Challenged by lysozymes, cells mainly exhibited cell wall damage, which seemed to increase with increasing lysozyme concentration and longer incubation period in the presence of ions. Cells with little as well as apparent lesion were observed under the same treatment set, and anomalous stick and huge rotund bodies were occasionally observed. After the removal of the lysozyme, some damaged cells could be reverted to its original form with brain heart infusion (BHI), and their growth curve was similar to the control cells. After further incubation in BHI containing lysozyme, S. sanguinis cell damage stopped progressing, and their growth curve was also similar to the control cells. The results suggested that the S. sanguinis lesions caused by the lysozyme in the oral cavity may be nonhomogeneous and that some damaged cells could self-repair and survive. It also indicated that S. sanguinis with damaged cell walls may survive and be transmitted in the bloodstream.

Topics: Animals; Anti-Infective Agents; Endocarditis, Bacterial; Humans; Microbial Viability; Microscopy, Electron; Mouth; Muramidase; Streptococcal Infections; Streptococcus sanguis

The percent weight gain (PWG) and feeding efficiency (FE) of Epinephelus coioides were calculated. The survival of Saccharomyces cerevisiae P13 in the posterior intestines using a specific primer pair of YMR245w-F/YMR245w-R, non-specific immune parameters of grouper, and its susceptibility to Streptococcus sp. and an iridovirus were determined when the fish were fed diets containing S. cerevisiae at 0 (control), 10(3), 10(5), or 10(7) colony-forming units (cfu) kg(-1) for 4 weeks. Results showed that grouper fed a diet containing S. cerevisiae at the levels of 10(3), 10(5), and 10(7) cfu kg(-1) had significantly increased PGW and FE especially in the 10(7) cfu kg(-1) group which were 211.6% and 1.2, respectively. S. cerevisiae was able to survive in the fish posterior intestines during the S. cerevisiae feeding period. Fish fed a diet containing S. cerevisiae at 10(7) cfu kg(-1) had significantly higher survival rates than those fed the 10(3) cfu kg(-1)S. cerevisiae diet and the control diet after challenge with Streptococcus sp. and an iridovirus, with increased survival rates of 26.6% and 36.6%, respectively, compared to the challenge control group. The phagocytic activity, respiratory burst and superoxide dismutase (SOD) level of head kidney leucocytes as well as serum lysozyme activity and serum alternative complement activity (ACH(50)) of fish fed diets containing S. cerevisiae at 10(5) and 10(7) cfu kg(-1) were significantly higher than those of fish fed the 10(3) cfu kg(-1)S. cerevisiae-contained diet and the control diets after 4 weeks of feeding, and had increased by 20% and 20%, 27.6% and 19.7%, 30.5% and 36.2%, 205.8% and 169.6%, and 90.8% and 80.3%, respectively, compared to the control group. We therefore recommend dietary S. cerevisiae administration of 10(5) and 10(7) cfu kg(-1) to E. coioides to promote growth and enhance immunity and resistance against Streptococcus sp. and an iridovirus especially in the 10(7) cfu kg(-1) group.

Topics: Animals; Body Weight; Complement Pathway, Alternative; Fish Diseases; Immunity, Innate; Muramidase; Perciformes; Phagocytosis; Probiotics; Respiratory Burst; Saccharomyces cerevisiae; Streptococcal Infections; Streptococcus; Superoxide Dismutase

The effect of Lactobacillus sakei BK19 (10(8) cells g(-1)) supplemented diet fed to kelp grouper, Epinephelus bruneus against streptococcosis caused by Streptococcus iniae and Streptococcus parauberis with reference to the innate immune response and disease resistance was evaluated at 1, 2, and 4 weeks. Maximum reduction in mortalities was observed in kelper feeding the probiotic diet for two weeks after challenged with the pathogens when compared to the infected group fed with basal diet; similarly the cellular and humoral immune responses such as head kidney macrophage phagocytic and peroxidase activities, serum lysozyme activity, and total protein levels increased significantly. The results reveal that, in streptococcosis infected kelp grouper feeding L. sakei BK19 enriched diet affords a higher level of disease protection due to stimulation of immune system.

Topics: Animals; Dietary Supplements; Fish Diseases; Lactobacillus; Macrophages; Muramidase; Perciformes; Peroxidase; Phagocytosis; Probiotics; Respiratory Burst; Streptococcal Infections; Streptococcus; Survival Analysis

Streptococcus suis is an important swine pathogen and a zoonotic agent. Differences in virulence have been noted among the 33 described serotypes, serotype 2 being considered the most virulent. In this study, we aimed at assessing the serotype distribution and the production of virulence-associated markers by strains recovered from diseased pigs in the United States (U.S.). Results showed that among the 100 strains evaluated, serotype 3 (20% of the isolates) and serotype 2 (17%) were the most prevalent. We then investigated the presence in these isolates of the genes sly, epf and mrp, encoding the virulence-associated markers suilysin (SLY), extracellular factor (EF) and muramidase-released (MRP) protein, respectively. The effective production of the markers by the strains was also verified. Results showed that the presence of the gene did not always correlate with actual expression of the respective protein. In the case of MRP, this was due, in most cases, to frameshift mutations at the 5' end of the gene resulting in premature stop codons. The most prevalent phenotypes among U.S. strains were MRP(+)EF(-)SLY(-) (40%) and MRP(-)EF(-)SLY(+) (35%). Serotype distribution greatly differed from that reported in several European countries, as did the production of virulence markers, particularly for serotype 2. On the other hand, our results for the U.S. S. suis isolates are similar to those reported for Canadian strains, suggesting a common status in North America.

Topics: Animals; Bacterial Proteins; Hemolysin Proteins; Muramidase; Phenotype; Serotyping; Streptococcal Infections; Streptococcus suis; Sus scrofa; Swine Diseases; United States; Virulence; Virulence Factors

Mozambique tilapia Oreochromis mossambicus acclimated to 27 degrees C were then held at 19, 23, 27 (control), 31 and 35 degrees C, and were examined for non-specific cellular and humoral responses after 12-96 h. Total leucocyte count decreased significantly when fish were transferred to 19 and 23 degrees C after 48 and 96 h, and when transferred to 35 degrees C over 12-96 h, respectively. Respiratory burst decreased significantly when fish were transferred to 19, 31 and 35 degrees C over 24-96 h, whereas phagocytic activity and phagocytic index decreased significantly when fish were transferred to low temperatures (19 and 23 degrees C) and high temperatures (31 and 35 degrees C) over 12-96 h. Lysozyme activity decreased significantly when fish were transferred to 19 degrees C after 12-96 h, but increased significantly when transferred to 31 and 35 degrees C over 48-96 h. Alternative complement pathway (ACH(50)) also decreased significantly when transferred to 19 and 23 degrees C after 12h, but increased significantly when transferred to 31 and 35 degrees C after 24h. In another experiment, tilapia reared at 27 degrees C were injected intraperitoneally with Streptococcus iniae at a dose of 1 x 10(7)colony-forming units (cfu)fish(-1), and then reared onward at water temperatures of 19, 23, 27 (control), 31 and 35 degrees C. Over 48-168 h, the cumulative mortality of S. iniae-injected fish held in 19 and 35 degrees C was significantly higher than that of injected-fish held in 23, 27 and 31 degrees C. It is concluded that transfer of tilapia O. mossambicus from 27 degrees C to low temperatures (19 and 23 degrees C) after 12h, and transfer of fish from 27 degrees C to high temperatures (31 and 35 degrees C) reduced their immune capability. Moreover, tilapia under temperature stress at 19 and 35 degrees C from 27 degrees C decreased its resistance against S. iniae.

Topics: Animals; Disease Susceptibility; Fish Diseases; Leukocyte Count; Leukocytes; Muramidase; Phagocytosis; Respiratory Burst; Streptococcal Infections; Streptococcus; Stress, Physiological; Temperature; Tilapia; Time Factors

The Streptococcus pneumoniae LytC lysozyme is responsible for autolysis at 30 degrees C (a temperature close to that of the upper respiratory tract), promotes DNA release in competent cultures, and participates in nasopharyngeal colonization. We show that the virulent pneumococcal TIGR4 strain encodes an active LytC enzyme, in contrast with genome-based predictions.

Topics: Base Sequence; Genome, Bacterial; Humans; Molecular Sequence Data; Muramidase; N-Acetylmuramoyl-L-alanine Amidase; Respiratory Tract Infections; Sequence Alignment; Sequence Homology, Nucleic Acid; Streptococcal Infections; Streptococcus pneumoniae

Group A streptococcus (GAS) is a leading cause of severe, invasive human infections, including necrotizing fasciitis and toxic shock syndrome. An important element of the mammalian innate defense system against invasive bacterial infections such as GAS is the production of antimicrobial peptides (AMPs) such as cathelicidins. In this study, we identify a specific GAS phenotype that confers resistance to host AMPs. Allelic replacement of the dltA gene encoding d-alanine-d-alanyl carrier protein ligase in an invasive serotype M1 GAS isolate led to loss of teichoic acid d-alanylation and an increase in net negative charge on the bacterial surface. Compared to the wild-type (WT) parent strain, the GAS DeltadltA mutant exhibited increased susceptibility to AMP and lysozyme killing and to acidic pH. While phagocytic uptake of WT and DeltadltA mutants by human neutrophils was equivalent, neutrophil-mediated killing of the DeltadltA strain was greatly accelerated. Furthermore, we observed the DeltadltA mutant to be diminished in its ability to adhere to and invade cultured human pharyngeal epithelial cells, a likely proximal step in the pathogenesis of invasive infection. Thus, teichoic acid d-alanylation may contribute in multiple ways to the propensity of invasive GAS to bypass mucosal defenses and produce systemic infection.

Topics: Alanine; Antimicrobial Cationic Peptides; Bacterial Adhesion; Cell Survival; Cells, Cultured; Epithelial Cells; Humans; Hydrogen-Ion Concentration; Muramidase; Mutagenesis; Neutrophils; Operon; Phagocytosis; Streptococcal Infections; Streptococcus pyogenes; Teichoic Acids; Virulence; Virulence Factors

Three feeding trials were conducted to evaluate potential immunomodulatory effects of nucleotides in the diet of hybrid striped bass. A basal diet was formulated from menhaden fish meal to contain 40% crude protein and 10% lipid. An oligonucleotide product (Ascogen P) from brewer's yeast was added to the basal formulation at the manufacturer's recommended rate of 0.5% to produce the experimental diet. Each diet was fed to four replicate groups of juvenile hybrid striped bass for seven or eight weeks in two separate trials. After Trials 1 and 2, a Streptococcus iniae bath challenge was executed to test the effects of diet on disease resistance. No significant difference in growth performance was observed between fish fed the basal and experimental diets. Body composition of whole fish, hematocrit and serum lysozyme levels were observed to be within normal ranges and not influenced by dietary nucleotides. Neutrophil oxidative radical production of fish fed the nucleotide-supplemented diet was significantly (P=0.011) higher than in fish fed the basal diet. Significantly (P<0.05) enhanced survival after exposure to S. iniae also was generally observed in fish fed the nucleotide-supplemented diet. In addition, fish fed the nucleotide-supplemented diet tended to have a higher antibody response based on microtitration agglutination; however, the difference was not statistically significant because of high variation between individual fish. Long-term (16 weeks) administration of oligonucleotides in Trial 3 failed to show enhancement of immune responses between treatments. It is concluded that dietary oligonucleotides positively influenced immune responses and resistance of juvenile hybrid striped bass to S. iniae infection.

Topics: Agglutination Tests; Animals; Bass; Body Composition; Diet; Fish Diseases; Hematocrit; Immunity, Innate; Muramidase; Oligonucleotides; RNA; Saccharomyces cerevisiae; Streptococcal Infections; Streptococcus

Human and bovine Streptococcus bovis strains had the same 16S ribosomal DNA restriction fragment length polymorphism and often had the same patterns of starch, mannitol, lactose, and raffinose utilization. PCRs of BOX sequences differed, but numerical analyses indicated that some human strains clustered with bovine strains. However, human and bovine strains had distinctly different sensitivities to lysozyme and 2-deoxyglucose.

Topics: Animals; Cattle; Cattle Diseases; Deoxyglucose; DNA, Ribosomal; Humans; Meningitis, Bacterial; Muramidase; Polymorphism, Restriction Fragment Length; RNA, Ribosomal, 16S; Streptococcal Infections; Streptococcus bovis; Substrate Specificity

Oral and pharyngeal cavities harbor a commensal bacterial flora which is kept in check by several innate and acquired agents. In this study, we focused on the proportions in which some antibacterial moderators (lysozyme, lactoferrin, IgG and S-IgA) coat the tonsillar surface bacteria in healthy individuals, in patients with acute tonsillitis (AT) culture-positive for Streptococcus pyogenes, and in patients with infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV).. Bacterial samples were collected for aerobic culturing and immunocytochemical evaluation from the tonsillar surfaces of eight healthy individuals (four males, four females; age range 16-22 years), eight patients with current AT (two males, six females; age range 16-29 years) and seven patients with IM (four males, three females; age range 15-21 years). The immunocytochemical assay was based on gold-labeled antiserum to human lysozyme, lactoferrin, IgG and S-IgA followed by gold particle tracing in the transmission electron microscope.. During AT, a significant increase in lysozyme coating (P<0.05) and lactoferrin coating (P<0.0005) of the bacteria was noted, whereas the S-IgA coating was significantly reduced (P<0.0005). During IM infection, a significant increase in lactoferrin coating was noted (P<0.0005) whereas immunoglobulin coating was significantly reduced (IgG P<0.025; S-IgA P<0.0005) compared with healthy controls. During IM, all antibacterial moderators evaluated were significantly reduced compared with the situation during AT.. Noticeable changes in the local innate and acquired bacterial defence system were observed during tonsillar infections, particularly during IM.

Topics: Acute Disease; Adolescent; Adult; Case-Control Studies; Female; Herpesvirus 4, Human; Humans; Immunity, Innate; Immunoglobulin A; Immunoglobulin G; Immunohistochemistry; Infectious Mononucleosis; Lactoferrin; Male; Muramidase; Palatine Tonsil; Streptococcal Infections; Streptococcus pyogenes; Tonsillitis

The effect of parenteral administration of two subcutaneous injections of vitamin E and Se (5 mg and 0.1 mg/kg of body weight, respectively) during the dry period on the mammary health and milk somatic cell counts of 25 dairy ewes was investigated. Supplementation reduced somatic cell counts (5.4 vs. 6.0 log10) during the subsequent lactation but had no effect on the incidence of clinical mastitis (4% vs. 6%) and intramammary infections (9.0% vs. 11.3%). Furthermore, the administration of vitamin E and Se was associated with differences in differential cell counts of milk samples (macrophages, 48.8% vs. 38.4%; polymorphonuclear neutrophils, 40.1% vs. 50.7%; and eosinophils, 0.7% vs. 1.4% for control ewes and ewes receiving supplements, respectively). The administration of these supplements also increased erythrocyte glutathione peroxidase activity (139.5 vs. 86.3 U/ml of packed cell volume) and the percentage of blood neutrophils that reduced nitroblue tetrazolium after bacterial extract stimulation (48.6% vs. 38.7%). Parenteral administration of vitamin E and Se to ewes during the dry period appeared to have influenced mammary gland status during the subsequent lactation and particularly total and differential milk cell counts.

Topics: Animals; Cell Count; Dietary Supplements; Female; Glutathione Peroxidase; Leukocyte Count; Lymphocytes; Macrophages; Mammary Glands, Animal; Mastitis; Milk; Muramidase; Neutrophils; Selenium; Sheep; Sheep Diseases; Staphylococcal Infections; Streptococcal Infections; Vitamin E

Nineteen Streptococccus suis type 2 isolates that had been analyzed previously for hemolysin production, ribotype, and virulence in pigs were examined for presence of the gene coding for suilysin by PCR amplification, and southern blot and hybridization techniques. Based on southern blot and hybridization analysis, all isolates tested contained at least a portion of the suilysin gene. PCR amplification of the entire gene resulted in gene fragments from five of the seven highly virulent isolates and none of the moderately virulent or avirulent isolates. Additional PCR analysis showed that mutation or deletions at the 5' end of the suilysin gene in the less virulent isolates prevented amplification of the sly gene fragment from those isolates. The MRP+ (muramidase-released protein) EF+ (extracellular protein) phenotype was also expressed by the same five highly virulent/sly+ isolates.

Topics: Animals; Bacterial Proteins; Blotting, Western; Electrophoresis, Polyacrylamide Gel; Gene Expression Regulation, Bacterial; Hemolysin Proteins; Muramidase; Organic Chemicals; Polymerase Chain Reaction; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases

Pentoxifylline was evaluated for its ability to enhance inactivation of group B streptococci in lungs of prematurely born rabbits. Mechanisms associated with intrapulmonary streptococcal clearance and the pharmacodynamics of pentoxifylline were also investigated.. Randomized, controlled animal trial.. University research laboratory.. A total of 123 New Zealand rabbits were delivered prematurely by cesarean section and were used for clearance studies. Twenty-three preterm pups were additionally utilized to study the pharmacodynamics of pentoxifylline.. Preterm rabbits were infected with group B streptococcal aerosols and given intraperitoneal injections of either pentoxifylline (25, 12.5, and 12.5 mg/kg) or placebo at 0, 6, and 12 hrs after infection.. At 0, 4, and 24 hrs, the numbers of streptococci were determined in the left lung, while the right lung underwent bronchoalveolar lavage to quantify intra-alveolar leukocytes, phagocytosis of inhaled bacteria, and concentrations of lysozyme and tumor necrosis factor. In a separate experiment, blood and bronchoalveolar fluid from infected animals were analyzed for pentoxifylline content. Streptococcal proliferation was less in pentoxifylline-treated animals than in controls at 24 hrs (p < .01). Pulmonary macrophages and polymorphonuclear leukocytes recovered from bronchoalveolar lavage fluid did not differ in numbers or phagocytic activity. Pentoxifylline-treated animals had lower levels of lysozyme (p < .02) and tumor necrosis factor (p < .005) in bronchoalveolar lavage fluid compared with placebo-treated pups. Therapeutic levels of pentoxifylline were achieved in blood and bronchoalveolar lavage fluid.. Despite lowering lysozyme and tumor necrosis factor content in epithelial lining fluid, pentoxifylline improves the inactivation of group B streptococci in preterm rabbit lungs. These findings suggest that increased group B streptococcal clearance was coincident with an anti-inflammatory effect due to pentoxifylline. We conclude pentoxifylline may be clinically useful as an adjunctive therapy for group B streptococcal pneumonia in newborns.

Topics: Animals; Animals, Newborn; Bronchoalveolar Lavage Fluid; Colony Count, Microbial; Disease Models, Animal; Drug Evaluation, Preclinical; Fetus; Leukocyte Count; Macrophages, Alveolar; Muramidase; Neutrophils; Pentoxifylline; Phagocytosis; Pneumonia; Rabbits; Random Allocation; Streptococcal Infections; Streptococcus agalactiae; Tissue Distribution; Tumor Necrosis Factor-alpha

To determine whether the virulence of Streptococcus suis type 2 is associated with the phenotype of the strain, we infected newborn germfree pigs with 10 strains of S. suis type 2 categorized by three phenotypes. In an earlier study, the phenotypes were distinguished by the presence or absence of the muramidase-released protein (MRP) and an extracellular factor (EF) and were designated MRP+ EF+, MRP+ EF- and MRP- EF-. Pigs were first inoculated with Bordetella bronchiseptica to predispose them to infection and were then intranasally inoculated with the streptococci. Strains of the MRP+ EF+ phenotype induced fever and increased the number of polymorphonuclear leukocytes in blood. Specific clinical signs of disease such as nervous disorders and lameness were also observed. At necropsy bacteriologic and pathologic examination disclosed meningoencephalitis, polyserositis, and polyarthritis. Strains of the MRP+ EF- phenotype induced only nonspecific clinical signs of disease such as recumbency, lack of appetite, and fever; only slight pathologic changes were detected in the serosae. The four strains of the MRP- EF- phenotype induced no signs of disease. These findings indicate that the 110-kDa EF and, to a lesser degree, the 136-kDa MRP may be associated with the virulence of the bacterium. The results demonstrated that S. suis type 2 strains producing both MRP and EF are pathogenic for pigs.

Topics: Animals; Animals, Newborn; Bacterial Proteins; Germ-Free Life; Muramidase; Phenotype; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases; Virulence

Streptococcus pneumoniae is an important bacterial pathogen in the pathophysiology of otitis media. To elucidate the inflammatory responses that occur during pneumococcal otitis media, the kinetics of the biochemical and cytologic middle ear responses to heat-killed encapsulated and nonencapsulated pneumococci were studied in the chinchilla model. Inoculation of the middle ear cavity with at least 10(6) S pneumoniae cells induced an early, brief vascular response with leakage of small (albumin) followed by larger (alpha 2-macroglobulin) proteins, followed by sustained influx of acute inflammatory cells and lysozyme. The threshold for a sustained lysozyme response was 1,000 times lower for nonencapsulated than for encapsulated pneumococci. These results indicate that nonviable S pneumoniae organisms with an intact envelope initiate the middle ear inflammatory response. Therefore, interventions that enhance the clearance of pneumococcal cells from the middle ear may reduce the inflammatory response and prevent chronic middle ear inflammation.

Topics: Albumins; alpha-Macroglobulins; Animals; Chinchilla; Muramidase; Neutrophils; Otitis Media; Otitis Media, Suppurative; Streptococcal Infections

Fifteen newborn germ-free pigs were inoculated with 2 strains, D-282 and T-15, of Streptococcus suis type II. Some pigs also were preinoculated with Bordetella bronchiseptica, which successfully predisposed them to S suis infection. The 2 streptococcal strains were differentiated by muramidase treatment, which released certain high molecular-weight proteins, termed muramidase-released proteins (MRP), from the cell wall of strain D-282, but not from the cell wall of strain T-15. Only strain D-282 (MRP-positive) induced clinical signs of disease and markedly increased neutrophil numbers in pigs. Streptococci were more frequently isolated from fecal swab specimens obtained from pigs inoculated with strain D-282 (MRP-positive) than from specimens obtained from pigs inoculated with strain T-15 (MRP-negative). Both strains were isolated from nasal swab specimens obtained from all infected pigs. Postmortem examination revealed fibrinopurulent meningitis, polyserositis, and polyarthritis in pigs inoculated with strain D-282; this strain was isolated from the CNS, serosae, visceral organs, heart, and joints. Whereas strains D-282 caused several pathologic changes, strain T-15, isolated from the lungs, caused only pneumonia. Both strains were isolated from the tonsils of all pigs. Virulence differed distinctly between the MRP-positive and the MRP-negative strains.

Topics: Animals; Animals, Newborn; Bacterial Proteins; Bordetella Infections; Cerebellum; Female; Germ-Free Life; Muramidase; Neutrophils; Species Specificity; Streptococcal Infections; Streptococcus; Swine; Swine Diseases; Virulence

The use of the discrete dynamic method for the treatment of data obtained in the survey of streptococcus carriers has made it possible to find out that their immune status is determined not so much by the quantitative changes in the results of individual immunological tests (for the bactericidal activity of the blood serum, lysozyme, IgG, IgM, IgA and the phagocytic activity of neutrophils), but, to a greater extent, by the interrelations of these characteristics. Significant differences in the interrelations of various humoral characteristics and in their relationship to the phagocytic process have been detected in the group of carriers as compared with the control group.

Topics: Adult; B-Lymphocytes; Blood Bactericidal Activity; Carrier State; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Muramidase; Neutrophils; Phagocytosis; Streptococcal Infections; Streptococcus pyogenes

The lysozyme activity in milk or exudate of 1028 cows, healthy or with various abnormal states of the mammary gland was determined in IU/ml. Normal milk from a healthy gland demonstrated a slight lysozyme activity-to 1,5 IU/ml. In exudate of a dry gland and in precolostral one the lysozymatic activity was distinct-to about 60 IU/ml. In latent infections the level of lysozyme was slightly higher than the normal. In various abnormal states of the mammary gland, there occurred a dependence between the level of the lysozyme activity and the number of nucleated cells and the virulence of bacteria. During treatment, as clinical changes subsided, the lysozyme activity in milk decreased gradually.

Topics: Animals; Cattle; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk; Muramidase; Staphylococcal Infections; Staphylococcus aureus; Streptococcal Infections; Streptococcus agalactiae

Topics: Bacitracin; Drug Combinations; Drug Evaluation; Muramidase; Papain; Pharyngitis; Staphylococcal Infections; Streptococcal Infections; Tonsillitis

Topics: Abortion, Septic; Adolescent; Adult; Anti-Bacterial Agents; Antitoxins; Carbenicillin; Cephalosporins; Complement System Proteins; Endometritis; Escherichia coli Infections; Female; Humans; Methicillin; Muramidase; Penicillin G; Pregnancy; Staphylococcal Infections; Streptococcal Infections; Tetracycline; Tetracyclines

Topics: Glomerulonephritis; Humans; Infections; Muramidase; Rheumatic Heart Disease; Saliva; Streptococcal Infections

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: Bacteriological Techniques; Conjunctivitis; Enterobacteriaceae Infections; Humans; Moraxella; Muramidase; Pneumococcal Infections; Proteus Infections; Staphylococcal Infections; Streptococcal Infections

Topics: Animals; Culture Media; L Forms; Mice; Muramidase; Penicillins; Streptococcal Infections; Streptococcus; Time Factors

Schwab, John H. (University of North Carolina, Chapel Hill). Biological properties of streptococcal cell-wall particles. I. Determinants of the chronic nodular lesion of connective tissue. J. Bacteriol. 90:1405-1411. 1965.-The capacity of cell-wall fragments to induce a chronic remittent nodular lesion after a single injection into rabbit skin varies qualitatively as well as quantitatively among the streptococci. This variation among strains is the result of a summation of several properties of the bacterial cell, some intrinsic and others extrinsic to the cell-wall structure. With some species, the inability to produce this lesion may be related to the susceptibility of cell walls to lysozyme. Other factors defined in this paper include production of hyaluronidase, and association of the cell walls with a component which can affect the interval between injection and appearance of the nodules, called the latent time. Separation of cell-wall fragments from more soluble cell material by centrifugation results in a shorter latent time. Addition of the soluble supernatant fraction back to the cell walls prolongs the latent time and increases the area of lesion involvement. This latter effect is due to a spreading factor present in most cell extracts. Addition of hyaluronidase to isolated cell-wall fragments duplicates the increased lesion area but tends to shorten further the latent time. Thus, the soluble cell extract contains both a spreading factor and a component which prolongs the latent time, and the final influence on the lesion is in part a product of these two activities. The ease and extent of mechanical disintegration of the cell wall can also vary widely among strains and yield cell extracts differing in their content of cell-wall fragments of optimal size.

Topics: Animals; Cell Membrane; Hyaluronoglucosaminidase; In Vitro Techniques; Muramidase; Rabbits; Skin; Streptococcal Infections; Streptococcus