Characterization of Gag and Nef-specific ELISpot-based CTL responses in HIV-1 infected Indian individuals

Med Microbiol Immunol. 2009 Feb;198(1):47-56. doi: 10.1007/s00430-008-0104-3. Epub 2008 Nov 5.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Cells, Cultured
  • Enzyme-Linked Immunosorbent Assay
  • Epitopes, T-Lymphocyte / analysis
  • Female
  • HIV Infections / immunology*
  • HIV Infections / virology*
  • HIV-1 / immunology*
  • Humans
  • Immunodominant Epitopes / analysis
  • India
  • Interferon-gamma / metabolism
  • Male
  • Peptide Fragments / metabolism
  • T-Lymphocytes, Cytotoxic / immunology*
  • Viral Load*
  • Young Adult
  • gag Gene Products, Human Immunodeficiency Virus / immunology*
  • nef Gene Products, Human Immunodeficiency Virus / immunology*

Substances

  • Epitopes, T-Lymphocyte
  • Immunodominant Epitopes
  • Peptide Fragments
  • gag Gene Products, Human Immunodeficiency Virus
  • interferon gamma (1-39)
  • nef Gene Products, Human Immunodeficiency Virus
  • nef protein, Human immunodeficiency virus 1
  • Interferon-gamma