Article
Genetic and biologic characterization of HIV type 1 subtype C isolates from south Brazil
Registro en:
MONTEIRO, J. P. Genetic and biologic characterization of HIV type 1 subtype C isolates from south Brazil. AIDS Research and Human Retroviruses, v. 23, n. 1, p. 135-143, 2007.
0889-2229
10.1089/aid.2006.0064
Autor
Monteiro, Joana Paixão
Ferraro, Geraldo Argolo
Oliveira, Tulio de
Goldani, Luciano Z
Kashima, Simone G
Alcantara, Luiz Carlos Junior
Morgado, Mariza Gonçalves
Bou-Habib, Dumith Chequer
Castro Filho, Bernardo Galvão
Resumen
Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB), the Brazilian Ministry of Health STD/AIDS Program, CNPq, and FIOCRUZ The molecular and biological properties of HIV-1 subtype C strains from South Brazil were investigated. We
sequenced gag and env fragments of viruses from 22 HIV-1-infected individuals from Porto Alegre City, which
has the highest frequency of subtype C in the country. The sequences were then compared with other subtype
B, C, and F strains isolated in Brazil and other countries using phylogenetic methods. Amino acid signatures
were identified and correlated with phenotypic characteristics. We identified six strains with subtype
C (27.3%), eight subtype B (36.4%), one subtype F (4.5%), six C/B recombinants (27.3%), and one B/F recombinant
(4.5%). The Brazilian subtype C sequences formed a unique phylogenetic group and presented 6
and 18 specific amino acid signatures in gag and env, respectively. Three distinct patterns of C/B recombinants
presented characteristic Brazilian amino acid substitutions. Subtype C viruses were predominantly R5
and non-syncytium-inducing, while C/B recombinants were R5/X4 and syncytium-inducing viruses. These
findings suggest that subtype C viruses circulating in Brazil are the result of a unique introduction into the
country. Recombination events between subtypes B and C have been occurring frequently for more than 10
years in South Brazil. Biological characterization confirms the hypothesis that subtype C is distinct from the
others in the evolution of coreceptor utilization.