Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.3.4.6 (urease)
 7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Detection of toxoplasma IgM antibodies by employing enzyme linked immunosorbent assay (ELISA) technique was developed using different enzymes viz, horseradish peroxidase (HRP) (EC. 1.11.17), urease (EC. 3.5.15) and penicillinase (EC 3.5.2.6) as markers. Of these enzymes, HRP is light sensitive and needs dark chamber, also inactivated by preservative sodium azide. Similarly urease test system is extremely pH sensitive and demands special care during ELISA technique. Whereas penicillinase showed certain distinct advantages viz. stable at room temperature, high specific activity and economical. In the present studies it was observed that the sensitivity of penicillinase is similar to HRP and urease, marker enzymes used in commercially available diagnostic kit. The prominent feature of detection of toxoplasma IgM antibodies involving these three enzymes are: a) Shorter incubation time (About 2.5 hours) b) No false positive reaction. Moreover, these enzyme conjugates were prepared from F (ab')2 fragments of antitoxoplasma rabbit serum to elicit specific interaction with IgM antibodies only, avoiding cross interaction with other non-specific proteins like compliment systems and rheumatoid factor.
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PMID:Detection of toxoplasma IgM antibodies by ELISA method: a comparative study of different enzymes as markers. 142 91

Besides various gastroduodenal diseases, Helicobacter pylori infection may be involved in autoimmune disorders like rheumatoid arthritis (RA) or idiopathic thrombocytopenic purpura. Such autoimmune disorders are often associated with autoreactive antibodies produced by B-1 cells, a subpopulation of B lymphocytes. These B-1 cells are mainly located in the pleural cavity or mucosal compartment. The existence of H. pylori urease-specific immunoglobulin A (IgA)-producing B cells in the mucosal compartment and of their specific IgM in the sera of acutely infected volunteers suggests the possibility that urease stimulates mucosal innate immune responses. Here, we show for the first time that purified H. pylori urease predominantly stimulates the B-1-cell population rather than B-2 cells, which produce antigen-specific conventional antibodies among splenic B220(+) B cells. The fact that such stimulation of B-1 cells was not affected by the addition of polymyxin B indicates that the effect of purified H. pylori urease was not due to the contamination with bacterial lipopolysaccharide. Furthermore, the production of various B-1-cell-related autoreactive antibodies such as IgM-type rheumatoid factor, anti-single-stranded DNA antibody, and anti-phosphatidyl choline antibody was observed when the splenic B cells were stimulated with purified H. pylori urease in vitro. These findings suggest that H. pylori components, urease in particular, may be among the environmental triggers that initiate various autoimmune diseases via producing autoreactive antibodies through the activation of B-1 cells. The findings shown here offer important new insights into the pathogenesis of autoimmune disorders related to H. pylori infection.
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PMID:Implications for induction of autoimmunity via activation of B-1 cells by Helicobacter pylori urease. 1636 78