title: Cross-Reactive Potential of HIV-1 Subtype C-Infected Indian Individuals Against Multiple HIV-1 Potential T Cell Epitope Gag Variants.
abstract: Vaccine immunogen with expanded T cell coverage for protection against HIV-1 diversity is the need of the hour. This study was undertaken to examine the ability of T cells to respond to a broad spectrum of potential T cell epitope (PTE) peptides containing variable as well as conserved sequences that would most accurately reflect immune responses to different circulating strains. Set of 320 PTE peptides were pooled in a matrix format that included 40 pools of 32 peptides per pool. These pools were used in interferon-γ enzyme-linked immunospot assay for screening and confirmation of HIV-1 PTE Gag-specific T cell immune responses in 34 HIV-1 seropositive Indian individuals. "Deconvolute This" software was used for result analysis. The dominant target in terms of magnitude and breadth of responses was observed to be the p24 subunit of Gag protein. Of the 34 study subjects, 26 (77%) showed a response to p24 PTE Gag peptides, 17 (50%) to p17, and 17 (50%) responded to p15 PTE peptides. The total breadth and magnitude of immune response ranged from 0.75 to 14.50 and 95.02 to 1,103 spot-forming cells/106cells, respectively. Seventy-six peptides located in p24 Gag were targeted by 77% of the study subjects followed by 51 peptides in p17 Gag and 46 peptides in p15 Gag with multiple variants being recognized. Maximum study participants recognized PTE peptide sequence Gag271→285NKIVRMYSPVSILDI located in p24 Gag subunit. T cells from HIV-1-infected individuals can recognize multiple PTE peptide variants, although the magnitude of the responses can vary greatly across these variants.
authors.affiliation: 1 Department of Microbiology, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Neema
authors.initials: N
authors.lastname: Negi
authors.affiliation: 1 Department of Microbiology, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Madhu
authors.initials: M
authors.lastname: Vajpayee
authors.affiliation: 2 Department of Pediatrics, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Ravinder
authors.initials: R
authors.lastname: Singh
authors.affiliation: 1 Department of Microbiology, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Sharma
authors.affiliation: 3 YRG Centre for AIDS Research and Education, Voluntary Health Services Hospital , Chennai, India .
authors.forename: Kailapuri G
authors.initials: KG
authors.lastname: Murugavel
authors.affiliation: 4 HIV-AIDS Laboratory, Molecular Biology & Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Bangalore, India .
authors.forename: Udaykumar
authors.initials: U
authors.lastname: Ranga
authors.affiliation: 5 Department of Immunology, National AIDS Research Institute (ICMR) , Pune, India.
authors.forename: Madhuri
authors.initials: M
authors.lastname: Thakar
authors.affiliation: 6 Department of Biostatistics, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Vishnubhatla
authors.initials: V
authors.lastname: Sreenivas
authors.affiliation: 1 Department of Microbiology, All India Institute of Medical Sciences , New Delhi, India .
authors.forename: Bimal Kumar
authors.initials: BK
authors.lastname: Das
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000328:Adult; D000595:Amino Acid Sequence; D003094:Collagen; D003429:Cross Reactions; D015195:Drug Design; D058501:Enzyme-Linked Immunospot Assay; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005260:Female; D015683:Gene Products, gag / Q000276:immunology*; D015658:HIV Infections / Q000517:prevention & control*; D006679:HIV Seropositivity / Q000276:immunology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D000071497:Immunogenicity, Vaccine; D007194:India; D008297:Male; D010446:Peptide Fragments; D010455:Peptides / Q000276:immunology*; D011446:Prospective Studies; D013601:T-Lymphocytes / Q000276:immunology*; D055815:Young Adult
chemical_list: D016915:AIDS Vaccines; D018984:Epitopes, T-Lymphocyte; D015683:Gene Products, gag; D010446:Peptide Fragments; D010455:Peptides; C407062:cell-binding peptide P-15; D003094:Collagen
keywords: Gag; HIV; potential T cell epitopes; subtype C; vaccine immunogen