Human Immunodeficiency Virus (HIV) Infections; Strain and Type Variations; Diagnosis and Prevention.

The studies described herein have focused on HIV variability, in particular on biologic and antigenic variability and its relevance for pathogenesis and for development of means for immune intervention. During the third year of the grant period we have intensified studies on molecular variability of HIV-1 and attempted to molecularly map biologic and antigenic determinants. Biologic characterization involved tests for replicative capacity, cytopathic effect and monocyte tropism of virus isolates and molecular clones, whereas antigenic characterization involved virus neutralization in autologous as well as heterologous system. By use of synthetic peptides, epitopes for virus neutralization and antibody dependent cellular cytotoxicity ADCC have been mapped in the envelope of HIV-1 and HIV-2. Variable region 3 V3 of the HIV-1 envelope has been studied in relation to biological and antigenic variation of HIV-1 isolates and in relation to mother-to-child transmission of HIV-1.