title: Human immunodeficiency virus (HIV) gag antigen-specific T-helper and granule-dependent CD8 T-cell activities in exposed but uninfected heterosexual partners of HIV type 1-infected individuals in North India.
abstract: Repeated exposure to human immunodeficiency virus (HIV) does not always result in HIV infection, and several cohorts of HIV-exposed but uninfected (EU) individuals have been described. We studied T-helper and granule-dependent cytotoxic T-lymphocyte (CTL) activities in a group of 30 EU partners of HIV type 1 (HIV-1)-infected individuals. HIV-1-specific helper-T-cell activity was studied by measuring the levels of interleukin 2 (IL-2) produced by peripheral blood mononuclear cells (PBMCs) and the granule-dependent CTL activity by measuring the intracellular levels of perforin and granzyme B expression in CD8+ T cells after stimulation with gag p24 antigen. Elevated IL-2 production by PBMCs after p24 stimulation occurred in EU individuals. The levels of perforin and granzyme B expression in CD8+ T cells were also higher among EU individuals than among healthy controls. HIV-specific helper-T-cell and granule-dependent CTL activities inversely correlated with the time since the last unprotected sexual exposure in these individuals. In our cohort, activation of T-helper and granule-dependent CTL activities against HIV might be due to unprotected sexual contact. These results indicate that HIV-1-specific T-cell responses could play a role in protection against acquiring infection in this cohort of EU individuals.
authors.affiliation: Department of Internal Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: Pallikkuth
authors.forename: Ajay
authors.initials: A
authors.lastname: Wanchu
authors.forename: Archana
authors.initials: A
authors.lastname: Bhatnagar
authors.forename: Ravinder Kaur
authors.initials: RK
authors.lastname: Sachdeva
authors.forename: Meera
authors.initials: M
authors.lastname: Sharma
mesh_terms: D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D015331:Cohort Studies; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005260:Female; D053804:Granzymes / Q000276:immunology / Q000378:metabolism; D016655:HIV Core Protein p24 / Q000235:genetics / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000635:transmission; D018023:HIV Seronegativity / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D020010:Heterosexuality; D006801:Humans; D007194:India; D007376:Interleukin-2 / Q000276:immunology; D008297:Male; D008875:Middle Aged; D054353:Perforin / Q000276:immunology / Q000378:metabolism; D012747:Sexual Partners; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D047568:Unsafe Sex