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Query: UMLS:C0003864 (arthritis)
 69,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the arthropathic activity of purified peptidoglycan (PG) fragments derived from (i) lysozyme-resistant, extensively O-acetylated PG from Neisseria gonorrhoeae FA19 (O-PG), and (ii) lysozyme-sensitive, O-acetyl-deficient PG from N. gonorrhoeae RD5 (non-O-PG). Male Lewis rats were injected intradermally in the tail with 200 micrograms of PG emulsified in mineral oil and water (1:1) or with the oil and water emulsion alone (controls). Quantitation of hind paw size indicated that macromolecular PG of various chemical and physical forms induced paw swelling (P versus controls, less than 0.01) that was evident at about day 14 and that reached a maximum at about day 24. PG-mediated paw swelling was accompanied by intense synovitis with some cartilage and bone involvement. The minimal arthropathic dose of soluble macromolecular PG was 20 micrograms per rat. Of particular interest was that macromolecular O-PGs from strain FA19 caused considerably more extensive swelling than did either their RD5 non-O-PG counterparts or the homologous FA19 PG that had been de-O-acetylated by mild alkali treatment. This suggested that the persistence of hydrolase-resistant high-molecular-weight fragments, afforded by extensive O-acetylation, may be important for optimal expression of arthropathic activity. However, oligomeric PG was not an absolute requirement, since even low-molecular-weight fragments, including the anhydro-muramyl-containing disaccharide peptide monomer released by growing gonococci, were also arthritogenic. Experiments employing purified gonococcal lipopolysaccharide indicated that the arthropathic activity of PG preparations was not due to contaminating lipopolysaccharide. Based on the arthritogenicity of gonococcal PG in this model system, we suggest that PG may play a role in the pathogenesis of gonococcal arthritis, and that such an activity might be potentiated by the persistence of hydrolase-resistant O-PG.
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PMID:Arthropathic properties of gonococcal peptidoglycan fragments: implications for the pathogenesis of disseminated gonococcal disease. 308 86

Streptococci and streptococcal cell wall fragments induce arthritis in rats, with the severity and duration depending on the capacity of the cells or cell fragments to resist degradation by tissue enzymes. Their phlogogenic effects are apparently related to their ability to activate the alternate complement pathway (ACP). The in vitro activation of the ACP by lysozyme-treated cells and cell walls of group A, B, and D streptococci suggests that both rat and human lysozyme can modulate this activity, i.e., increasing it, decreasing it, or doing both in that order. The effects of the lysozymes also correlated with the degree to which they can unmask the aminosugar-reducing groups detectable in a given amount of cell wall, which suggests that partial depolymerization of the cell wall is critical for ACP activation. The effects of mutanolysin and C phage lysin on ACP activation were found to be correlated with their action on streptococcal cell walls. Neuraminidase had relatively little effect on ACP activation by most streptococcal strains tested. We conclude that the participation of tissue enzymes, including but not necessarily limited to lysozyme, is an important determinant for the clinical arthritis induced by group A, B, or D streptococci. Experimental arthritis induced in rats with whole (or disrupted) streptococci may depend both on the capacities of the cell walls to activate the ACP and on the capacities of the host tissue enzymes to modulate this activation. Great severity and long durations of the disease were determined by the capacity of the enzymes to degrade cell wall antigens to a degree sufficient to ensure efficient activation of the ACP without completely degrading the material so that it no longer activates complement. In this model, the limited resistance of group B peptidoglycan to lysozyme was a critical pathogenic factor.
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PMID:Modulation of complement fixation and the phlogistic capacity of group A, B, and D streptococci by human lysozyme acting on their cell walls. 308 32

A new method for measuring DNA antibody forming cells (DNA-AFC) using the enzyme-linked immunospot (ELISPOT) assay is described. This method uses enzyme-linked immunosorbent assay (ELISA) techniques applied to cells cultured on DNA-coated plates, which allows visual quantitation of spots representing imprints of specific antibodies from DNA-AFC. Specificity for DNA was confirmed by inhibition studies and lack of reactivity by anti-lysozyme hybridomas. Isotypes of IgG and IgM can be measured using the appropriate antisera in the assay. A study of 16 female (New Zealand black x New Zealand white)F1 ([NZB x NZW]F1) female mice showed significant correlation between age, rising blood urea nitrogen levels, and increasing proteinuria and increasing numbers of DNA-AFC. In contrast, the correlation between circulating antibodies to DNA (ELISA method) and clinical parameters of nephritis was not significant. Both the native DNA ELISPOT and the native DNA ELISA had similar significant linear correlations with age. This is the first report of use of the ELISPOT assay for measurement of DNA-AFC. The DNA-AFC measured by this method were specific and correlated with the presence of clinical nephritis in (NZB x NZW)F1 mice. This method should allow further study on the regulation of DNA-AFC in vitro and in vivo, and will be useful in the investigation of DNA-AFC and cellular mechanisms of autoimmunity.
Arthritis Rheum 1986 Sep
PMID:Detection of native and denatured DNA antibody forming cells by the enzyme-linked immunospot assay. A clinical study of (New Zealand black x New Zealand white)F1 mice. 353 Feb 55

Purified group A streptococcal peptidoglycan-polysaccharide (PG-PS) fragments were either de-O-acylated, or acetylated and then de-O-acylated to yield N-acetylated PG-PS. Native PG-PS was poorly degraded, N-acetylated PG-PS was extensively degraded, and de-O-acylated PG-PS was only slightly degraded by hen egg white lysozyme. N-acetylated PG-PS was also extensively degraded by human lysozyme and partially degraded by rat serum or rat liver extract. After a single intraperitoneal injection of rats with a sterile, aqueous suspension, all PG-PS preparations induced acute arthritis. The acute arthritis induced by N-acetylated PG-PS was significantly more severe than that induced by native PG-PS; that induced by de-O-acylated PG-PS was of intermediate severity. After the acute reaction, rats injected with native PG-PS developed chronic relapsing erosive synovitis which remained severe for the duration of the experiment (83 days). In contrast, joint inflammation induced by N-acetylated PG-PS resolved within 6 weeks with little evidence of recurrent disease. Chronic arthritis induced by de-O-acylated PG-PS was of intermediate severity. In another assay of arthropathic activity, the arthritis in all rat ankle joints, which had been injected directly with native PG-PS, could be reactivated 3 weeks later by the intravenous injection of a small dose of PG. In contrast, only 50% of the joints initially injected with de-O-acylated PG-PS and none of the joints injected with N-acetylated PG-PS could be reactivated. These studies support the concepts that the resistance of PG-PS to muralytic digestion is crucial for chronic arthropathic activity and that the nature and degree of PG acetylation are important molecular determinants of the phlogistic activities of PG-PS polymers.
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PMID:Effect of acetylation on arthropathic activity of group A streptococcal peptidoglycan-polysaccharide fragments. 353

A new method for the measurement of lysozyme activity, which is rapid, quantitative and sensitive, was established and applied to clinical material obtained from arthritis patients. The method is based on fluorescence polarization with the use of fluorescein isothiocyanate-labeled peptidoglycan. Using this method, we found that the synovial fluids obtained from rheumatoid arthritis contained more lysozyme activity than similar samples from osteoarthritis patients (P less than 0.001). Furthermore, we found that chemotactic factors and lysozyme-depleted rheumatoid synovial fluids could induce the release of lysozyme from human polymorphonuclear leukocytes in vitro. It is therefore suggested that lysozyme present in rheumatoid synovial fluids may derive in part from polymorphonuclear leukocytes and the action of chemotactic factor(s) within the fluids.
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PMID:Determination of lysozyme activity by fluorescence polarization in rheumatoid synovial fluids and release of lysozyme from polymorphonuclear leukocytes by chemotactic factors. 366 59

Bacterial cell wall induced arthritis is an experimental model of chronic erosive synovitis in which arthritis is induced in rats by a single injection of an aqueous suspension of cell wall fragments from selected Gram-positive bacteria. To understand better the Gram-positive bacterial cell wall characteristics necessary for the induction of chronic arthritis we tested the arthritogenicity of five Gram-positive bacteria which were (1) lysozyme resistant and contained a polyrhamnose peptidoglycan side chain moiety, (2) lysozyme resistant, but had little or no rhamnose in the peptidoglycan, polysaccharide, or (3) neither lysozyme resistant, nor contained rhamnose in their peptidoglycan, polysaccharide. All of the lysozyme resistant cell walls tested induced acute arthritis, but only those cell walls which were both lysozyme resistant and contained rhamnose in their polysaccharide side chain were able to induce chronic arthritis. Cell walls which were neither lysozyme resistant nor contained rhamnose were not arthritogenic. These data suggest that both lysozyme resistance and the rhamnose moiety in the peptidoglycan, polysaccharide side chain play an important role in the induction of chronic arthritis by Gram-positive bacterial cell walls in aqueous suspension.
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PMID:Bacterial cell wall composition, lysozyme resistance, and the induction of chronic arthritis in rats. 393 Dec 1

Lysozyme (LZM) concentrations in synovial fluid were determined in patients with seropositive and seronegative rheumatoid arthritis (RA) and in patients whose arthritic exudates had been caused by Reiter's disease, a Yersinia enterocolitica infection, osteoarthritis, or trauma. Patients with rheumatoid disease had significantly higher levels of lysozyme in synovial fluid than patients with non-rheumatic diseases. The concentration of lysozyme correlated with the number of polymorphonuclear leukocytes in synovial fluid in seronegative--but not in seropositive--rheumatoid arthritis. In patients with rheumatic arthritis the lysozyme level correlated inversely with the concentration of glucose in synovial fluid. In patients with rheumatoid pleural effusion, lysozyme levels in pleural fluid were comparable to those in serum. The concentration of LZM in thoracic duct lymph was roughly the same as in serum. During drainage of thoracic duct lymph, the lysozyme level in serum decreased.
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PMID:Lysozyme concentrations in synovial fluid, pleural fluid and thoracic duct lymph in rheumatoid arthritis. 400 80

Activated platelets release substances which potentially can contribute to joint lesions in inflammatory arthritides. To elucidate a possible participation of platelets in inflammatory joint reactions, the concentrations of the platelet protein beta-thromboglobulin (beta-TG) were measured in 90 inflammatory synovial fluids. Seven percent of the patients with rheumatoid arthritis and none of the patients with other inflammatory joint diseases (e.g., Reiter's disease, reactive or crystal arthritides) had beta-TG concentrations in synovial fluid exceeding the upper normal range of plasma beta-TG. The absent or very modest signs of local platelet activation were contrasted by the pronounced neutrophilic and monocytic activation, as assessed by the measurements of some granule proteins: lactoferrin, myeloperoxidase, lysozyme, and ferritin. No correlation was found between these inflammatory cell markers and beta-TG. A positive correlation (p less than 0.001) was noted between beta-TG and beta 2-microglobulin, which appeared in particularly high amounts in rheumatoid arthritis. This correlation may reflect a disturbed permeability of synovial membrane for LMW proteins or a related activation of platelets and lymphocytes. The present results do not give any evidence of platelet activation playing a major role in proliferative or destructive processes in arthritis.
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PMID:Beta-thromboglobulin in inflammatory synovial fluid. 619 77

Neutrophils were preincubated with 17 beta-estradiol and progesterone to determine the effects of these hormones on chemotactic peptide-stimulated superoxide anion (O2-) generation and degranulation. At pharmacologic levels 17 beta-estradiol was more active than progesterone with respect to inhibition of O2- generation as well as degranulation. An increase of preincubation time from 5 minutes to 25 minutes increased the percent inhibition. When 17 beta-estradiol and progesterone were combined at levels which approximate those measured during gestation, there was small but significant inhibition of O2- generation. Dexamethasone at equal molar concentration inhibited O2- generation only after 25 minutes of preincubation and at no time reached the level of inhibition attained by either of the sex hormones alone. Both estradiol and progesterone at pharmacologic levels significantly inhibited beta-glucuronidase and lysozyme release, whereas dexamethasone did not inhibit degranulation despite prolonged preincubation. Neutrophils isolated from women during various phases of the menstrual cycle and during the third trimester of pregnancy did not differ with respect to chemotactic peptide-stimulated O2- generation. These data suggest that inhibition of neutrophil responses requires the continuous presence of pharmacologic levels of estradiol and progesterone.
Arthritis Rheum 1984 Jun
PMID:Female hormones reduce neutrophil responsiveness in vitro. 632 34

It was established in rat experiments that adaptation to altitude hypoxia leads to the enhancement of immune response to sheep red blood cells and to an increase in the serum lysozyme level. Adaptation to altitude hypoxia also suppresses adjuvant arthritis and prevents arthritis-induced inhibition of antibody production.
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PMID:[Effect of adaptation to altitude hypoxia on the nonspecific immunity indices, production of hemagglutinins and development of adjuvant arthritis in rats]. 737 59


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