8th International AIDS Conference Amsterdam, Netherlands — July 19-24, 1992

Int Conf AIDS 1992 Jul 19-24; 8:We49 (abstract no. WeC 1024)
Kuiken CL, Zwart G, Baan E, Coutinho RA, Goudsmit J; HRL, UvA, Amsterdam.

OBJECTIVE: To investigate the evolution of the gp120 V3 region in the course of the HIV-1 epidemic in the Dutch homosexual population. MATERIALS AND

METHODS: Direct sequences, 278 nucleotides long, were made of viral genomic RNA amplified from early seroconverter sera of homosexual men. Ten sequences were generated from around 1980, and 10 each from 1985 and 1990. Reactivity of sera to synthetic V3-mimicking peptides was measured using ELISAs.

RESULTS: The V3 loop (Cys-Cys) became more diverse (mean difference between sequences 3.9%, 5.7% and 8.6% respectively in 1980, 1985 and 1990). Outside V3, the diversity was already at 8% in 1980 and the increase was much less marked. Comparing only silent changes over the whole region, the diversity increased from 8.87% in 1980 to 15.75% in 1990, whereas non-silent changes remained stable. Despite of the increased variability, no continuous change was found in the consensus sequences, indicating that there is no movement of the swarm of viruses in a particular direction. Amino acid 308, of particular importance to antibody reactivity, showed more variation in 1990 than in earlier years. Reactivity to 3 peptides designed to discriminate at this position also showed this diversification, consistent with earlier findings of our group [Zwart et al., in preparation].

CONCLUSIONS: The V3 region becomes increasingly diverse as the epidemic progresses. The data suggest that the V3 loop will become a more elusive target region for vaccine-induced antibodies over time.

Copyright © 1992 - International AIDS Society (IAS). Reproduction of this abstract (other than one copy for personal reference) must be cleared through the IAS.