Anti-phospholipid antibodies and CD5(+) B cells in HIV infection

This cross-sectional study evaluates the correlation between anti-phospholi pid antibodies and CD5(+) B cells in 110 patients infected with HIV-1. Ther e were 89.1% of the patients who had IgG antibodies against cardiolipin and phosphatidylserine. The prevalence of IgM and IgA antibodies was < 22%. AI DS was associated with lower frequencies of IgM antibodies against cardioli pin (P=0.05) and IgG-antibodies against cardiolipin and phosphatidylserine (P=0.011). Drug users had higher IgM antibodies against phospholipids than patients from other risk groups (P=0.02). A history of thromboembolic event s was not accompanied by higher levels of anti-phospholipid antibodies (P>0 .2). No correlation between anti-phospholipid antibodies and CD5(+) B cells was detected. Percentage part of CD5(+) B lymphocytes was elevated in all patients and absolute CD4(+) T lymphocyte counts and HIV p24 antigen were i nversely correlated. In advanced disease a significant reduction of anti-ph ospholipid antibodies was contrasted with persistent elevation of CD5(+) B lymphocytes. These observations may reflect immunological dysfunction invol ving apoptosis and endothelial damage rather than polyclonal B cell hyperst imulation. A possible explanation would be that in HIV infection an increas ed rate of spontaneous apoptosis in peripheral blood lymphocytes is accompa nied by functional and structural changes of mitochondria. Therefore, struc turally altered mitochondrial phospholipids could serve as antigen to induc e specific humoral immune responses.