Genetic characterization of HIV type 1 and type 2 from Bissau, Guinea-Bissau (West Africa).
Previous studies from Guinea-Bissau (West Africa) have demonstrated a unique epidemiology with respect to both HIV-1 and HIV-2 infection. In order to evaluate the prevalence and dynamics of HIV-1 and HIV-2 subtypes in Bissau, the capital city of Guinea-Bissau, a cross-sectional study was set up using serological and molecular techniques. Plasma samples from 103 individuals were screened for HIV-1 and HIV-2 antibodies by ELISA and Western-blot. Seropositive results were confirmed by PCR amplification of proviral sequences in primary peripheral blood mononuclear cells (PBMC) with env and LTR primer sets for HIV-2 and env, LTR and pol primers for HIV-1. A total of 38/103 individuals were HIV-seroreactive (four HIV-1, 15 HIV-2, 19 HIV-1/HIV-2). A total of eight out of 19 dually seropositive specimens showed double PCR amplification of HIV-1 and HIV-2 proviral sequences, accounting for 21% of the infected individuals. In the remaining 11 individuals either HIV-2 or HIV-1 sequences were detected, the majority (n=9) amplifying only HIV-2. These screening data demonstrate a high discrepancy between serology and PCR results for dually seroreactive samples, Western-blot giving an overestimation of double infection. Additionally, HIV-1 strains were subtyped by heteroduplex mobility assay (HMA) on the basis of gp120 sequences. Subtyping of HIV-2 was carried out by DNA sequencing and phylogenetic analysis of env V3 molecular clones. For both HIV-1 and HIV-2 strains circulating in Bissau, our results indicate dominance of subtype A.
Unidade de Virologia/UPMM, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 96, P-1349-008, Lisboa, Portugal. aidaesteves@ihmt.unl.pt
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A
Esteves
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Parreira
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J
Piedade
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Venenno
W F
WF
Canas-Ferreira
D000293:Adolescent; D000328:Adult; D000595:Amino Acid Sequence; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004279:DNA, Viral / Q000097:blood; D005260:Female; D015686:Gene Products, env / Q000235:genetics; D006169:Guinea-Bissau / Q000453:epidemiology; D015483:HIV Antibodies / Q000097:blood; D015699:HIV Envelope Protein gp120 / Q000235:genetics; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics*; D015498:HIV-2 / Q000145:classification* / Q000235:genetics*; D020180:Heteroduplex Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011533:Proviruses; D017422:Sequence Analysis, DNA; D054299:env Gene Products, Human Immunodeficiency Virus
D004279:DNA, Viral; D015686:Gene Products, env; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D054299:env Gene Products, Human Immunodeficiency Virus; C069790:gp105 envelope protein, Human immunodeficiency virus 2