Lymphadenopathy-associated virus type 2 in AIDS and AIDS-related complex. Clinical and virological features in four patients.

Lymphadenopathy-associated virus type 2 (HIV 2) was isolated from 3 patients with AIDS and 1 with AIDS-related complex. Clinical features were similar to those in patients infected with HIV 1. Viral isolates were characterised by hybridisation with HIV 1 and HIV 2 DNA probes. HIV 1 and HIV 2 serological studies were performed by enzyme-linked immunosorbent assay (ELISA), western blot, and radioimmunoprecipitation assay. HIV 2 IgG antibodies were detected in all sera. The molecular weights of the most representative HIV 2 proteins were determined by immunoblot. Cross-reactivity was restricted to HIV 1 and HIV 2 core proteins. In all 4 patients the neurotropism of HIV 2 was demonstrated by virus isolation from the cerebrospinal fluid and/or by evidence of intrathecal HIV 2 IgG synthesis. All sera were antibody negative by HIV 1 ELISA. An assay specific for HIV 2 is needed for screening of blood donations and for diagnosis and seroepidemiological study of HIV 2 infection.