Molecular epidemiology and MT-2 cell tropism of Russian HIV type 1 variant.
Twenty-two HIV-1-infected Russian individuals were studied to gain better insight on the genetic and biological characteristics of HIV-1 variants present in Russia. The V3 domain of the HIV-1 envelope was directly sequenced from cultured peripheral blood mononuclear cells (PBMCs). Phylogenetic analyses were used to determine the HIV-1 genetic subtype and to study transmission patterns. Virus isolates were obtained from PBMCs and the biological phenotype was determined by coculture with MT-2, CEM, and Jurkat-tat cells. Twelve homo- and bisexual men carried subtype B variants, whereas 6 heterosexually infected individuals carried subtype F virus. A heterosexual man infected in the Ivory Coast and a nosocomially infected young female carried subtype A and G virus, respectively. Interestingly, phylogenetic analyses suggested that subtype B may have entered Russia on at least four occasions and, even more surprisingly, that the relatively rare subtype F has entered Russia on at least three occasions. Two suspected transmission clusters of subtype F were supported by the phylogenetic analyses, whereas one suspected subtype B transmission cluster was not. Positively charged amino acids in positions 311 and 325 of V3 loop have been shown to be important determinants for the MT-2-positive biological phenotype of virus isolates. Interestingly, we found that the direct PBMC sequences from individuals with MT-2-positive isolates displayed specific neutral, instead of positively charged, amino acids, in these positions. This indicates that it may be more difficult to predict the biological phenotype of HIV-1 using sequences from uncultured PBMCs than from virus isolates.
Leitner
T
T
Department of Clinical Virology, Swedish Institute for Infectious Disease Control, Karolinska Institute, Stockholm, Sweden.
Korovina
G
G
Marquina
S
S
Smolskaya
T
T
Albert
J
J
D000595:Amino Acid Sequence; D001483:Base Sequence; D002461:Cell Line, Transformed; D004279:DNA, Viral; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D015699:HIV Envelope Protein gp120 / Q000235:genetics; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D006801:Humans; D019169:Jurkat Cells; D008297:Male; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics; D010641:Phenotype; D012426:Russia / Q000453:epidemiology; D014407:Tumor Cells, Cultured
D004279:DNA, Viral; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments