title: Characterization of Gag and Nef-specific ELISpot-based CTL responses in HIV-1 infected Indian individuals.
abstract: Cytotoxic T lymphocyte (CTL) responses to Gag have been most frequently linked to control of viremia whereas CTL responses to Nef have direct relationship with viral load. IFN-gamma ELISpot assay was used to screen CTL responses at single peptide level directed at HIV-1 subtype C Gag and Nef proteins in 30 antiretroviral therapy naive HIV-1 infected Indian individuals. PBMCs from 73.3% and 90% of the study population showed response to Gag and Nef antigens, respectively. The magnitude of Gag-specific CTL responses was inversely correlated with plasma viral load (r = -0.45, P = 0.001), whereas magnitude of Nef-specific responses was directly correlated (r = 0.115). Thirteen immunodominant regions (6 in Gag, 7 in Nef) were identified in the current study. The identification of Gag and Nef-specific responses across HIV-1 infected Indian population and targeting epitopes from multiple immunodominant regions may provide useful insight into the designing of new immunotherapy and vaccines.
authors.affiliation: Department of Microbiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Mendiratta
authors.forename: Madhu
authors.initials: M
authors.lastname: Vajpayee
authors.forename: Uma
authors.initials: U
authors.lastname: Malhotra
authors.forename: Shweta
authors.initials: S
authors.lastname: Kaushik
authors.forename: Lalit
authors.initials: L
authors.lastname: Dar
authors.forename: Kamalika
authors.initials: K
authors.lastname: Mojumdar
authors.forename: Neeraj Kumar
authors.initials: NK
authors.lastname: Chauhan
authors.forename: Vishnubhatla
authors.initials: V
authors.lastname: Sreenivas
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D018984:Epitopes, T-Lymphocyte / Q000032:analysis; D005260:Female; D015658:HIV Infections / Q000276:immunology* / Q000821:virology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D016056:Immunodominant Epitopes / Q000032:analysis; D007194:India; D007371:Interferon-gamma / Q000378:metabolism; D008297:Male; D010446:Peptide Fragments / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D019562:Viral Load; D055815:Young Adult; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000276:immunology*; D054311:nef Gene Products, Human Immunodeficiency Virus / Q000276:immunology*
chemical_list: D018984:Epitopes, T-Lymphocyte; D016056:Immunodominant Epitopes; D010446:Peptide Fragments; D054301:gag Gene Products, Human Immunodeficiency Virus; C069261:interferon gamma (1-39); D054311:nef Gene Products, Human Immunodeficiency Virus; C514837:nef protein, Human immunodeficiency virus 1; D007371:Interferon-gamma