Association of Antibody to Human Immunodeficiency Virus Type 1 Core Protein (p24), CD4 Lymphocyte Number, and AIDS-Free Time

Serum antibody to p24 (anti-p24) and p24 antigen, alone and in combination with CD4+ lymphocyte number, were evaluated as predictors of progression of human immunodeficiency virus type 1 (HIV-1) infection. Two hundred six HIV-I-prevalent seropositive men in the Multicenter AIDS Cohort Study since 1984–1985 were studied cross-sectionally and 84 seroconverters were evaluated longitudinally. Cross-sectional analyses revealed significant associations among titer of anti-p24, CD4+ cell count, disease status (Centers for Disease Control class), and progression to AIDS. A high titer of anti-p24 was associated with lack of p24 antigenemia. Longitudinal studies of seroconverters demonstrated that a low titer of anti-p24, low CD4+ cell count, and detection of HIV-I p24 antigen are individually strong predictors of AIDS, but only low CD4+ cell count retains its independent predictive value in multivariate analysis of the three markers during the period immediately after infection with HIV-1.