Acid pH-induced changes in the immunoreactivity of specific antigen and antibody in circulating immune complexes from tuberculosis sera
✍ Scribed by Uday Kumar; R. K. Saxena
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 508 KB
- Volume
- 6
- Category
- Article
- ISSN
- 0887-8013
No coin nor oath required. For personal study only.
✦ Synopsis
The effect of acid pH treatment of circulating immune complexes (CIC) derived from tuberculosis sera was studied on the relative titers of specific antibody (CIC Ab) and mycobacterial antigen (CIC Ag) in the complexes. While the specific antibody titers increased, the titers of CIC Ag declined as a result of acid pH treatment of CIC, both changes being highly significant statistically. Direct exposure of TB sera to pH 2.8 also resulted in significant enhancements in the titers of antibodies directed against Mycobacteriurn fuberculosis (M.tb.). Competition experiments indicated that the acid pH-treated antibodies retained their antigen specificity. TB sera treated with pH 2.8 for 30 min and then neutralized back to pH 7.4 retained the enhanced antibody reactivity even after 7 days of storage at 4°C. Our results indicate that acid pH treatment induces higher antigen binding ability in anti-M.tb. antibodies, present in free or complexed form in TB sera. These changes appear to be irreversible. Dissociation of CIC and analyzing the titers of released antibody and antigen components offered no advantage with respect to the immunodiagnosis of tuberculosis, as compared to the levels of undissociated CIC components or the serum antibody. o 1992 Wiiey-Liss, inc.