A comparison of full-length glycoprotein 120 from incident HIV type 1 subtype E and B infections in Bangkok injecting drug users with prototype E andB strains that are components of a candidate vaccine

Complete gp120 sequence information was obtained from eight persons with in cident HIV-1 infections (four subtype E and four subtype B) who were part o f a prospective injecting drug user (IDU) cohort in Bangkok, Thailand, duri ng 1996-1998. The incident subtype E strains were similar to the prototype subtype E strain CM244 isolated in 1992 in northern Thailand. The incident subtype B strains displayed divergence, in both overall genetic distance an d other significant gp120 characteristics, from the prototype North America n subtype B strain HIV-MN. Recombinant gp120s derived from CM244 and HIV-MN strains are components of a vaccine that is undergoing phase III efficacy testing, begun in March 1999, among Bangkok area IDUs. The information pres ented here will be important in the evaluation of any breakthrough HIV-1 in fections occurring among vaccinees during the vaccine trial and in ongoing vaccine development efforts in Thailand.