Immunologic and virologic studies in long-term non-progressor HIV infected individuals. NOPHROCO Study Group. Non...

The study of epidemiological, virological and immunological parameters in HIV+ patients defined as long-term non-progressors (LTnP) could be the key to knowledge of the natural history of HIV disease and its therapeutical approach. The aim of this study was to identify the factors that delay the onset of HIV related symptoms in patients with HIV disease with low rate of progression. We studied several individuals defined as LTnP according to the following criteria. The patients were asymptomatic with HIV infection documented for at least 8 years, they had never received antiretroviral treatment and their CD4 levels were always above 500/cmm. They were studied every 6 months for the following tests: viral isolation, characterization of viral strain; quantitative DNA-PCR; serum p24 HIV antigen, plasma viremia, neutralizing antibodies versus primary autologous and heterologous isolates. The immunological study includes a large panel of monoclonal antibodies to characterize lymphocyte phenotype, cellular proliferation with mitogen and antigens (tetanus toxoid; GMP of C. Albicans, p24 and gp160 of HIV), specific cytoxicity for HIV (env and gag) and spontaneous cellular mortality rate. Surnatants from lymphocyte cultures (stimulated with PHA) are collected to measure cytokines (IL2; IL4; IL10; gamma IFN) and T cell clones are grown to characterize the phenotype and cytokine pattern. Here we report only a summary of immunological data collected.