muramidase and Rheumatic-Diseases

As the lysozyme story continues to unfold, rheumatic disease is one area where the study of this fascinating protein will be most important. The special biochemical features of lysozyme--its hexosaminidase function, its ability to bring about transglycosylation, its homology to alpha-lactalbumin, and its cationic nature--suggest that the connective tissues may prove to be the key to the understanding of the function of lysozyme. As methods for its accurate measurement become standardized, better data on the activity of the enzyme in various tissues and body fluids, in both health and disease, will be forthcoming. As additional studies are done to ascertain which of the hypothetical functions attributed to lysozyme are of significance in vivo, it will be the student of the connective tissues and the diseases thereof who can be expected to profit most from an udnerstanding of the role of lysozyme in mammalian biology.

Topics: Calcification, Physiologic; Cartilage; Connective Tissue; Humans; Muramidase; Rheumatic Diseases; Synovial Fluid; Tears

ANCA-positive sera from 1138 patients and ANCA-negative sera from 90 patients were screened for autoantibodies directed against lysozyme (LZ) by ELISA. Sera from 120 patients did react with LZ. 99 sera bound to LZ only, whereas 56 sera bound to further granule proteins, especially cathepsin G and lactoferrin. In the routine ANCA screening, most of the anti-LZ-positive sera showed a pANCA fluorescence. In total, 8% of 674 pANCA-positive sera did react with LZ. Clinically, anti-LZ antibodies were associated inflammatory rheumatologic, -renal and -bowel diseases.

Topics: Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Autoantibodies; Glomerulonephritis; Humans; Inflammatory Bowel Diseases; Muramidase; Rheumatic Diseases; Vasculitis

Topics: Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Autoantibodies; Autoantigens; Cathepsin G; Cathepsins; Fluorescent Antibody Technique; Humans; Muramidase; Myeloblastin; Pancreatic Elastase; Peroxidase; Rheumatic Diseases; Serine Endopeptidases

Topics: Adolescent; Adult; Ascorbic Acid; Female; Humans; Immunity, Innate; Lactates; Lactic Acid; Male; Middle Aged; Muramidase; Oxidation-Reduction; Rheumatic Diseases

Monocytes isolated from peripheral blood of patients with various rheumatic diseases and circulating immune complexes (IC) developed a significantly higher thromboplastin (tissue factor) activity than normal cells when cultured in vitro without inducers, but normal cells responded more strongly with thromboplastin production upon stimulation with IC or phytohaemagglutinin (PHA). Sera from patients with rheumatic diseases and circulating IC induced a significant increase in the thromboplastin activity of normal monocytes. Lysozyme release from patient monocytes was significantly lower than the release from control cells when stimulated with IC. Patient sera contained higher amounts of lysozyme than normal sera, indicating lysozyme release in vivo. These data suggest that activation of monocytes in vivo by IC may take place. The increased expression of thromboplastin in monocytes/tissue macrophages may be important for the development of microvascular thrombosis and fibrin deposition seen in chronic inflammatory lesions.

Topics: Adolescent; Adult; Aged; Antigen-Antibody Complex; Arthritis, Rheumatoid; Female; Glucuronidase; Humans; Male; Middle Aged; Monocytes; Muramidase; Rheumatic Diseases; Thromboplastin

1. The permeability of the synovial membrane for proteins is larger in rheumatoid arthritis than in osteoarthrosis, in rheumatoid arthritis with high CRP activity larger than in rheumatoid arthritis with low CRP activity. 2. The diffusion by the synovial membrane in most plasma proteins takes place depending on their molecular weight. Of the 14 proteins tested only haptoglobin and fibrinogen did not follow this regularity. 3. While the non-immune proteins proved in the synovial fluid only come from the blood plasma, the immune globulins IgG, IgA, and IgM as well as lysozyme are partly also locally synthetized and enriched in rheumatoid arthritis. In rheumatoid arthritis lysozyme is present in the synovia not only in free, but in most cases also in cell-bound form.

Topics: Arthritis, Rheumatoid; Blood Proteins; C-Reactive Protein; Humans; Immunoglobulins; Molecular Weight; Muramidase; Osteoarthritis; Permeability; Rheumatic Diseases; Synovial Membrane

After reviewing previous work on the subjects, the authors show that the synovial fluid in subjects with inflammatory rheumatism contained higher levels of lysozyme and of beta-glucuronidase comparable with those of the acid phosphatases and of lacto-dehydrogenase that they were interested in previously.

Topics: Acid Phosphatase; Arthritis, Rheumatoid; Glucuronidase; Humans; Knee Joint; L-Lactate Dehydrogenase; Muramidase; Rheumatic Diseases; Synovial Fluid