COMPARATIVE-STUDY OF ANTIBODIES THAT ARE ASSOCIATED WITH DISEASE PROGRESSION IN HIV DISEASE

Two types of antibodies which previously were found to be inversely as sociated with CD4(+) cell counts and which may contribute to the progr ession of HIV disease were measured in parallel in 55 serum samples of 7 longitudinally tested HIV-infected patients (4 homosexual men, 3 ha emophilic men) and in 15 serum samples from 15 patients with advanced AIDS. HIV-infection enhancing antibodies were determined in the presen ce of near-physiologic human complement concentration using a compleme nt receptor type 2 (CR2) carrying HIV-target cell line. IgG and IgA cl ass autoantibodies directed against human IgG-Fab fragments were measu red in specific ELISA assays. In agreement with our previous studies o btained in HIV-seropositive haemophilic patients, significant negative correlations were found between CD4(+) cell counts and IgG anti-Fab a nd IgA anti-Fab antibodies (Spearman correlation coefficient r = -0.58 7, P < 0.0001; and r = -0.269, P = 0.024, respectively). A significant positive correlation was observed between complement-dependent enhanc ing antibodies and IgA anti-Fab antibodies (r = 0.408, P = 0.003), whe reas the correlation with IgG anti-Fab antibodies was only weak (r = 0 .288, P = 0.034). Serum samples with high titres of complement-depende nt enhancing antibodies had almost 3 times higher IgA anti-Fab autoant ibody activity than sera with low titres (P = 0.0038). Our findings in dicate that the two disease markers in HIV disease, enhancing antibodi es and autoantibodies directed against the Fab moiety of IgG, are not identical. However, anti-Fab antibodies may contribute to complement-d ependent HIV infection enhancement.