title: Neutralizing antibody responses in recent seroconverters with HIV-1 subtype C infections in India.
abstract: The longitudinal heterologous neutralization response against two HIV-1 subtype C isolates was studied in 33 ART-naive individuals recently infected with HIV-1 subtype C from India. Seven of 33 (21%) seroconverters demonstrated a consistent response against both isolates (65-100% neutralization), whereas the remaining 26 (79%) were nonresponders. Four of the seven responders demonstrated a neutralization response (>75% neutralization) within 2-3 months of infection and in the remaining three, the response was demonstrated between 22 and 38 months after infection. In the past, HIV vaccines targeted the V3 region for the development of neutralizing antibodies. However, recent studies have shown that anti-V3 antibodies are generated after HIV-1 infection, but are not effective in neutralizing virus. In this study, the V3 sequences of HIV-1 from seven responders were analyzed and compared with those from nonresponders. The V3 region sequences from early and late responders did show certain mutations that were not found in the nonresponders; however none of these mutations could explain the neutralization responses. This suggested that HIV-1 envelope regions other than the V3 domain may be involved in generating a neutralization response. This is the first report that describes the pattern of emergence and persistence of the heterologous neutralization response in recently HIV-1 subtype C-infected individuals from India and studies its association with sequence variation in the V3 region.
authors.affiliation: National AIDS Research Institute, Pune 411 026, India. skulkarni@nariindia.org
authors.forename: Smita
authors.initials: S
authors.lastname: Kulkarni
authors.forename: Srikanth
authors.initials: S
authors.lastname: Tripathy
authors.forename: Raman
authors.initials: R
authors.lastname: Gangakhedkar
authors.forename: Sushama
authors.initials: S
authors.lastname: Jadhav
authors.forename: Kalpana
authors.initials: K
authors.lastname: Agnihotri
authors.forename: Suvarna
authors.initials: S
authors.lastname: Sane
authors.forename: Robert
authors.initials: R
authors.lastname: Bollinger
authors.forename: Ramesh
authors.initials: R
authors.lastname: Paranjape
mesh_terms: D000595:Amino Acid Sequence; D018791:CD4 Lymphocyte Count; D005838:Genotype; D015483:HIV Antibodies / Q000097:blood*; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000145:classification / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007194:India; D008137:Longitudinal Studies; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D017422:Sequence Analysis, DNA; D013997:Time Factors; D019562:Viral Load; D054299:env Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000276:immunology
chemical_list: D015483:HIV Antibodies; D054299:env Gene Products, Human Immunodeficiency Virus