DISTINCT BUT RELATED HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 VARIANT POPULATIONS IN GENITAL SECRETIONS AND BLOOD

For a HIV vaccine to be effective, it will be essential that it protec t against the virus variants to which individuals are most frequently exposed, HIV-1 is predominantly a sexually acquired virus, thus, varia nts in genital secretions are a potentially important reservoir of vir uses that are transmitted, Because there are no data available on vari ants in the genital mucosa, we analyzed this provirus population and c ompared it to the proviruses in the blood of individuals chronically i nfected with HIV-1. A major genetic difference between variants within a patient were insertions, which were apparently created by duplicati on of adjacent sequences, that resulted in acquisition of new potentia l glycosylation sites in V1 and V2, Comparisons of mucosal and PBMC va riants suggest that these tissues harbor distinct, but related populat ions of HIV-1 variants, In two of three patients, the mucosal variants were most closely related to a minor variant genotype in blood, In a third individual, viruses in both tissues were surprisingly homogeneou s, but the majority of variants in the cervix encoded a V1 sequence wi th a predicted glycosylation pattern similar to a minor variant in blo od, The V3 sequence patterns of the mucosal isolates indicate they may be predominantly macrophage-tropic viruses.