STRIKING INVERSE CORRELATION BETWEEN IGG ANTI-F(AB')(2) AND AUTOANTIBODY PRODUCTION IN PATIENTS WITH COLD AGGLUTINATION

Previous experiments showed that the physiologic IgG anti-F(ab')(2) an tibody suppresses the response of human autoreactive B cells. In the p resent study, we analyzed the IgG anti F(ab')(2) antibody in 293 patie nts with cold agglutination (CA). Their average IgG anti-F(ab')(2) tit er was not much different (211 +/- 8.3) from that of 279 healthy perso ns (195 +/- 6.7). However, CA patients with high anti-F(ab')(2) titers had low CA autoantibody titers and vice versa (P = .0028; rho = -0.17 5). The stratification of patients according to the auto-antibody's sp ecificity (anti-l, anti-i, anti-Pr) showed an inverse correlation betw een anti-F(ab')(2) and CA in the anti-l group (P = .0057; rho = -0.180 ). Interestingly, the association was present only in patients whose d isease was caused by noninfectious agents (P < .0001; rho = -0.423). T he inverse correlation argues for an important role of the IgG anti-F( ab')(2) in the regulation of autoantibody production in CA patients. ( C) 1995 by The American Society of Hematology.