AEGiS-11IAC: HIV-1 diversity in patients from Rio De Janeiro, Brazil.

11th International AIDS Conference

Vancouver, British Columbia — July 7-12, 1996

HIV-1 diversity in patients from Rio De Janeiro, Brazil.

Int Conf AIDS 1996 Jul 7-12; 11:216 (abstract no. Tu.A.103)
Morgado MG, Guimaraes ML, Gripp CB, Costa CI, Santos VG, Linhares-Carvalho MI, Bastos FI, Galvao-Castro B, Castilho EA, Bongertz V; Dept. of Immunology -Instituto Oswaldo Cruz, Brasil.

OBJECTIVE: Three HIV-1 subtypes, B, F and C have been found in Brazil up now, in addition to a recombinant B/F genome, with a clear predominance of subtype B isolates. Moreover, those studies have also shown that many Brazilian subtype B isolates present a typical amino acid composition (GWGR) at the conserved crown of the gp 120 V3 loop, suggesting that subtype B isolates could be split in two main groups, one corresponding to the USA/European consensus B sequence and a second one, called B', typically found in Brazil. The aim of this work is to follow HIV-1 diversity in Rio de Janeiro City and try to correlate the subtype distribution with exposure categories.

METHODS: HIV-1 samples analyzed up to now were obtained from positive individuals from two cohorts followed at medical centers in Rio de Janeiro, BR (Evandro Chagas Hosp-FIOCRUZ and Ambulatn consensus B sequence and a second one, called B', typically found in Brazt centers or in the streets. DNA samples were PCR amplified by a nested protocol using an outer primer set which amplifies a 2.0Kb fragment spanning from the first exon of REV up to the transmembrane protein gp41 coding region of ENV. For the 2nd round PCR, the inner primer sets covering respectively the V1-V5 or C2-C3 regions of the HIV-1 ENV were used. HIV-1 subtyping was determinate by heteroduplex mobility assay as described elsewhere (Delwart et al.1993, Science 262:1257-61).

RESULTS: We have analyzed 102 individuals, 57 men and 45 women, which were distributed by the exposure categories as follows: 17 homosexual & 10 bisexual men; 49 heterosexuals (8 men), 16 IDUs (one woman) and 10 without available information. From the eighty-one HIV-1 samples typed until now, 73 (90%) were included as subtype B and 8 (10%) as subtype F. No significant statistical association (Fisher's exact test) was identified cross-comparing HIV-1 subtypes with exposure categories, genres and transmission routes. Discrimination between B and B' patterns is under evaluation.

CONCLUSIONS: No segregation between HIV-1 subtypes and exposure categories was identified in Rio de Janeiro. A tendency of increasing the frequency of the HIV-1 F subtype was observed when compared to our previous results (Morgado et al. 1994 AIDS Res Hum Retrv., 10:569-576), where only one F subtype was identified among 18 DNA samples obtained from asymptomatic individuals from 1990 to 1992, although with no statistical significance, possibly due to the small sample size evaluated up now. (Supported by WHO/GPA/VDU, PIAF/FIOCRUZ and UNDP/World Bank/PN-DST/AIDS, BR.)

Keywords: AEGIS, HIV-1, Acquired Immunodeficiency Syndrome, Heterosexuality, Polymerase Chain Reaction, Homosexuality, Brazil, Human, Male, Female, ICA11

960707
TuA103