title: Evidence of no change in V3 loop antibody recognition pattern in HIV type 1-infected Ethiopians between 1988 and 1993.
abstract: To determine the antibody reactivity against a V3 sequence based on local HIV-1 strains in Ethiopia, 635 serum samples derived in 1988 and 1993 were analyzed by peptide enzyme immunoassays. V3 peptides were produced according to the Ethiopian subtype C V3 consensus sequence (RKSIRIGPGQTFYAT), the HIV-1MN and HIV-1IIIB strains (subtype B), and the consensus sequences of subtypes A, D, and E. Initial analyses showed that Ethiopian anti-V3 positive sera cross-reacted between subtype A and subtype C peptides, and displayed much lower reactivities to the other peptides. Using inhibition experiments, it was found that the reactivities in the Ethiopian samples were specific for subtype C. A strong reactivity to the Ethiopian V3 consensus sequence was found in the majority of the Ethiopian samples (59%), independent of geographical origin or year of sampling. In Swedish HIV-1-positive sera, the high reactivities were restricted to the subtype B HIV-1MN peptide. A low prevalence (10%) of strong reactivity to the HIV-1MN V3 peptide was found among the Ethiopian samples. Using substitution peptide analogs it was found that a lack of cross-reactivity between subtype B and C peptides was dependent on the Arg-322 to Gln-322 substitution. The present data show that a similar antibody recognition pattern was present in sera sampled during 1993 as in sera sampled during 1988, suggesting that subtype C of HIV-1 has remained the dominant subtype in Ethiopia.
authors.affiliation: Department of Immunology, Microbiology, Pathology, and Infectious Diseases, Karolinska Institute, Huddinge University Hospital, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Sherefa
authors.forename: M
authors.initials: M
authors.lastname: Sällberg
authors.forename: A
authors.initials: A
authors.lastname: Sönnerborg
mesh_terms: D000595:Amino Acid Sequence; D016384:Consensus Sequence; D000939:Epitopes / Q000235:genetics; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D015483:HIV Antibodies / Q000097:blood; D015488:HIV Antigens / Q000235:genetics*; D015699:HIV Envelope Protein gp120 / Q000235:genetics* / Q000276:immunology*; D015658:HIV Infections / Q000453:epidemiology / Q000276:immunology* / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010446:Peptide Fragments / Q000235:genetics* / Q000276:immunology*; D013997:Time Factors
chemical_list: D000939:Epitopes; D015483:HIV Antibodies; D015488:HIV Antigens; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments