muramidase and Foreign-Body-Reaction

The interest of marine invertebrates as food resources provides a major interest to study molluscan immunity for better understanding of the host response to pathogens. Molluscs possess a natural immunity formed by anatomical and chemical protective barriers that prevent damage of the underlying tissues, body fluid losses and the infections of pathogenic microorganisms and parasites. The main physical barrier is shell and mucus which cover the soft body of molluscs. The integrity of body coverings is supported by blood clotting and wound healing. The internal defense mechanisms of molluscs involve such cellular reactions as: phagocytosis, nodule formation, encapsulation, pearl formation, atrophy, necrosis and tissue liquefaction. Granular hemocytes are the most numerous cell type of molluscan blood active in cellular defenses. Invaders small in size are eliminated by phagocytosis in which participate lectins and products of prophenyloxidase system activation. Numerous and large intruders are eliminated by nodule formation or encapsulation, either cellular or humoral. Humoral components of molluscan immunity are formed by lysozyme activity, lectins and the phenyloxidase system. Up to now the role of mercenenes, paolins, acute phase reactants, alpha 2-macroglobulins and multifunctional binding proteins with anti-protease activity is not well clarified yet. Research prospects on the field of molluscan immunology should essentially be devoted to study cellular defense functions and humoral effectors to select pathogen-resistant molluscs. This aim could also be achieved by the identification and characterization of immune genes which are candidates for molluscs genetic transformation.

Topics: Animals; Biomphalaria; Catechol Oxidase; Enzyme Precursors; Foreign-Body Reaction; Hemagglutinins; Hemocytes; Host-Parasite Interactions; Immunity, Innate; Mollusca; Muramidase; Phagocytosis; Schistosoma mansoni; Self Tolerance

The immune system functions to counteract the wide range of pathogens an insect may encounter during its lifespan, ultimately maintaining fitness and increasing the likelihood of survival to reproductive maturity. In this study, we describe the maturation of the innate immune system of the male house cricket Acheta domesticus during the last two nymphal stages, and during early and late adulthood. Total hemolymph phenoloxidase enzyme activity, lysozyme-like enzyme activity, the number of circulating hemocytes, and encapsulation ability were all determined for each developmental stage or age examined. The number of circulating hemocytes and lysozyme-like enzyme activity were similar for all developmental stages examined. Nymphs and newly molted adult males, however, had significantly lower total phenoloxidase activity than later adult stages, yet nymphs were able to encapsulate a nylon thread just as well as adults. Encapsulation ability would thus appear to be independent of total phenoloxidase activity.

Topics: Animals; Foreign-Body Reaction; Gryllidae; Hemocytes; Hemolymph; Immunity, Innate; Male; Monophenol Monooxygenase; Muramidase; Nymph

Glycol chitosan (GC), a chitosan derivative conjugated with ethylene glycol, is soluble in water at a neutral/acidic pH and is viscous. This GC was incorporated into poly(lactide-co-glycolide) (PLGA) microparticles (prepared by the multi-emulsion W(1)/O/W(2) (water-in-oil-in-water) method) to stabilize lysozyme (Lys) used as a model protein. Herein, GC's viscous property helped to improve Lys encapsulation efficacy and reduce Lys denaturaton at the water/organic solvent interface. When the GC concentration in the W(1) phase increased, the formation of non-covalent Lys aggregates decreased. This may be because the aqueous microdroplets surrounded by the firm viscous interface protect Lys from the degrading environment formed by the water/organic solvent interface. In an in vitro Lys release test, 40mg incorporation of GC led to continuous Lys release of up to 78wt.% for 1 month and presented bioactivity of more than 95% for Lys released from microparticles. In addition, there was negligible immune response in the tissue treated with the GC-incorporated PLGA microparticles, whereas there was a moderate foreign body reaction in the muscle layer and many configurations of neutrophils in the tissue treated with the PLGA microparticles without GC. It is expected that GC facilitates a decrease in immune responses exacerbated as a consequence of PLGA degradation.

Topics: Animals; Chitosan; Foreign-Body Reaction; Lactic Acid; Male; Materials Testing; Microspheres; Muramidase; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Polymers; Proteins; Rats; Rats, Sprague-Dawley; Solubility

Flow cytometry was used to quantify apoptotic and necrotic polymorphonuclear (PMN) cells in an exudate generated by biomaterials, and the results were compared with determinations of spontaneous apoptosis and necrosis in PMN cells from the bloodstream. The exudate formed inside cylindrical tubes subcutaneously implanted in the dorsal region of rats was collected over a 1-week period. A rapid and simple staining procedure based on the spectral properties of the bisbenzemide Hoechst 33342 was used to identify apoptotic PMN cells. Quantification of permeabilized PMN cells stained by propidium iodide was possible in the same unfixed specimens. The percentages of apoptotic and permeabilized PMN cells in peripheral rat blood were low (1.8 +/-0 0.5% and 1.7 +/- 0.7%, respectively), similar to results found in humans. In exudates generated by polyvinyl chloride (PVC), the percentages of apoptotic and permeabilized PMN cells were higher than in the blood. The percentage of PMN cells undergoing apoptosis progressively increased with time and reached a maximum at day 2 (27% +/- 6%). The percentage of permeabilized cells progressively increased with time and was much higher than the percentage of apoptotic cells on days 4 and 8. Apoptosis and necrosis of PMN cells at day 2 were inhibited when tubes were filled with 10% serum. Selective inhibition of apoptosis with a caspase inhibitor in vivo indicated that apoptosis and necrosis are two separate pathways leading to the death of PMN cells in the exudate. At day 2, polyurethane (PU) was associated with a lower rate of apoptosis than PVC or a random copolymer of trimethylene carbonate (TMC) and epsiloncaprolactone (ECL). Apoptosis was interpreted as an organized cell removal process that limits inflammation. Apoptosis was the natural route of PMN cell death at the early stage of inflammation.

Topics: Animals; Apoptosis; Biocompatible Materials; Cell Membrane Permeability; Cells, Cultured; Cysteine Proteinase Inhibitors; Exudates and Transudates; Fibroblasts; Flow Cytometry; Foreign-Body Reaction; Humans; Lactones; Male; Materials Testing; Muramidase; Necrosis; Neutrophils; Polyesters; Polymers; Polyurethanes; Polyvinyl Chloride; Prostheses and Implants; Prosthesis Implantation; Rats; Rats, Wistar; Time Factors

The objective of this study was to investigate the cellular tissue response to temporomandibular joint (TMJ) Proplast-Teflon disc material by morphologic and immunohistochemical means.. Twelve patients who had been subjected to TMJ discectomy combined with insertion of a Proplast-Teflon interpositional implant (PTIPI) were recalled for removal of the alloplastic disc. The time elapsed between the Proplast-Teflon disc implantation and its removal varied between 13 and 71 months (mean, 54.6 +/- 5.8 [SEM]) The implants and periimplant tissues were examined by light microscopy and immunohistochemically using a panel of monoclonal antibodies reactive with different subclasses of leukocytes. The sections were immunostained using the alkaline phosphatase-antialkaline phosphatase (APAAP) technique.. Fibrosis and a massive foreign body giant cell reaction were seen inside the heavily disrupted alloplastic implants and in the periimplant tissues. CD68-positive monocyte-derived cells dominated the reactive infiltrate in the implants and surrounding tissue. The CD68-positive cells also were partly positive for lysozyme. The lymphocytic infiltration contained no B cells.. This study of the PTIPI-induced tissue reaction gave no indication of a toxic or an immunologic pathogenesis. Mechanical stress seems important in the fragmentation of the implant and induction of the foreign body reaction. It is not yet known if this fragmentation is the major contributing factor.

Topics: Adult; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Bite Force; Female; Fibrosis; Foreign-Body Reaction; Giant Cells; Humans; Immunoenzyme Techniques; Joint Prosthesis; Male; Middle Aged; Monocytes; Muramidase; Proplast; Reoperation; Stress, Mechanical; Temporomandibular Joint Disorders

The lysozyme activity in tissue samples from patients with lupus miliaris disseminatus faciei (LMDF), sarcoidosis and foreign body granuloma was investigated using the immunoperoxidase technique. The majority of epithelioid cells and giant cells in LMDF and sarcoidosis showed strong lysozyme staining in their cytoplasm. However, most macrophages and giant cells in foreign body granulomas, including granulomatous reactions to epidermal cysts and other foreign materials, stained weakly for lysozyme or were negative. These results suggest that LMDF is different from the foreign body reaction to inert substances, and may be induced by an immunological mechanism associated with cell-mediated immunity.

Topics: Adult; Aged; Female; Foreign-Body Reaction; Granuloma; Humans; Immunoenzyme Techniques; Lupus Vulgaris; Male; Middle Aged; Muramidase; Sarcoidosis; Skin

The muramidase content of reactive cells in the lesions of human foreign body reactions, lepromatous and tuberculoid leprosy, sarcoidosis, tuberculosis, and granulomatous hepatitis, was assessed using specific anti-human muramidase antiserum and a peroxidase-anti-peroxidase marker system. Epithelioid and giant cells in sarcoidosis, tuberculosis, granulomatous hepatitis, and tuberculoid leprosy all showed the presence of muramidase in their cytoplasm. The muramidase content of macrophages in foreign body reactions and lepromatous leprosy varied and most multinucleate cells in these lesions gave a negative reaction. Possibly varying rates of muramidase secretion may account for these differences.

Topics: Cytoplasm; Foreign-Body Reaction; Hepatitis; Humans; Leprosy; Lung; Lymph Nodes; Muramidase; Sarcoidosis; Tuberculosis

Lysozyme activity of macrophages and giant cells in various human granulomas were examined with immunoperoxidase bridge method in tissue sections. Various numbers of epithelioid cells and giant cells of epithelioid cell granulomas of tuberculosis, sarcoidosis and Crohn's disease exhibited intense granular cytoplasmic lysozyme activity. Foreign body granulomas induced with various substances showed negative or faintly positive lysozyme stain. Macrophages and giant cells of aspergillus granuloma associated with thymus hypoplasia and T-cell depression contained no lysozyme. The results suggest that cell-mediated immunology plays an important role for the lysozyme synthesis of macrophages in granuloma.

Topics: Aspergillosis; Child, Preschool; Crohn Disease; Foreign-Body Reaction; Granuloma; Humans; Macrophages; Muramidase; Sarcoidosis; T-Lymphocytes; Thymus Gland; Tuberculosis

Factors determining thrombus formation on a foreign surface were studied with the use of plastic flow chambers introduced into extracorporeal shunts. Silicone rubber shunts, joining the carotid artery and jugular vein, were implanted in dogs and remained patent for several weeks. The flow chamber geometry consisted of a 4.8 mm diameter straight tube having a 3.2 X 3.2 mm circumferential cavity in the wall. Chambers were introduced sequentially into the shunts for exposure times of 10 to 30 minutes and regulated blood flow rates of 100 to 400 ml/min. The dry weight of thrombus accumulated in the chamber (5 to 50 mg) was found to increase with exposure time up to 20 minutes and to decrease with increasing flow rate. Various components of the process of thrombus formation were altered by the administration of acetylsalicylic acid, heparin and lysozyme, used alone and in pairs. Heparin was found to be the most effective antithrombotic agent, dry weights of accumulated thrombus being on the order of 50 percent lower when compared to control values. The efficacy of heparin was found to be unaffected by the presence of aspirin and lysozyme, which themselves were not effective antithrombotic agents under the conditions of these experiments. The technique described here may provide a useful animal model for studying the influence of blood flow and different biomaterials on thrombus formation.

Topics: Animals; Aspirin; Blood Coagulation; Blood Flow Velocity; Disease Models, Animal; Dogs; Drug Synergism; Extracorporeal Circulation; Foreign-Body Reaction; Heparin; Muramidase; Platelet Aggregation; Rheology; Silicone Elastomers; Thrombosis; Time Factors