T-cell Epitopes Identified by BALB/c Mice Immunized with Vaccinia Expressing HIV-1 Gag lie within immunodominant Regions Recognized by HIV-infected Indian Patients.

Abstract

BACKGROUND:

Human immunodeficiency virus (HIV) antigens from transmitted strains of HIV would prove crucial in vaccine designing for prevention of HIV infection. Immune response generated by Vaccinia construct expressing the HIV-1 gag gene from transmitted Indian HIV-1 subtype C strain (Vgag) in BALB/c mice is reported in the present study along with the identification of epitopes responsible for induction of the immune response.

AIMS:

The aim of this study was to determine immune response generated by the constructs in a mouse model and to understand the epitope specificities of the response.

SETTINGS AND DESIGN:

This was an observational study carried out in BALB/c mice.

MATERIALS AND METHODS:

The immunogenecity of Vgag construct was evaluated in BALB/c mice after multiple immunizations. T-cell response was monitored by the interferon-γ ELISPOT assay using HIV-1 C Gag overlapping peptides and anti-P24 antibodies were estimated by ELISA.

STATISTICAL ANALYSIS USED:

Graphpad prism software was used for statistical analysis and for plotting graphs.

RESULTS:

IFN-γ-secreting T cells and antibodies were detected against HIV Gag in mice after immunization. Although after repeated immunizations, antibody-mediated immune response increased or remained sustained, the magnitude of IFN-γ-secreting T cell was found to be decreased over time. The Gag peptides recognized by mice were mainly confined to the P24 region and had a considerable overlap with earlier reported immunodominant regions recognized by HIV-infected Indian patients.

CONCLUSION:

Vaccinia construct with a gag gene from transmitted HIV-1 virus was found to be immunogenic. The Gag regions identified by mice could have important implications in terms of future HIV vaccine designing.

• Authors: Ashwini V Shete, Madhuri R Thakar, Srikanth P Tripathy, Cg Raut, Sekhar Chakrabarti, Ramesh S Paranjape
• Journal: Journal of global infectious diseases (J Glob Infect Dis) Vol. 3 Issue 3 Pg. 246-53 (Jul 2011) ISSN: 0974-8245 [Electronic] India
• PMID: 21887056 (Publication Type: Journal Article)