Evaluation of antiviral T cell responses and TSCM cells in volunteers enrolled in a phase I HIV-1 subtype C prophylactic vaccine trial in India

PLoS One. 2020 Feb 25;15(2):e0229461. doi: 10.1371/journal.pone.0229461. eCollection 2020.

Abstract

T cells play an important role in controlling viral replication during HIV infection. An effective vaccine should, therefore, lead to the induction of a strong and early viral-specific CD8+ T cell response. While polyfunctional T cell responses are thought to be important contributors to the antiviral response, there is evidence to show that polyfunctional HIV- specific CD8+ T cells are just a small fraction of the total HIV-specific CD8+ T cells and may be absent in many individuals who control HIV replication, suggesting that other HIV-1 specific CD8+ effector T cell subsets may be key players in HIV control. Stem cell-like memory T cells (TSCM) are a subset of T cells with a long half-life and self-renewal capacity. They serve as key reservoirs for HIV and contribute a significant barrier to HIV eradication. The present study evaluated vaccine-induced antiviral responses and TSCM cells in volunteers vaccinated with a subtype C prophylactic HIV-1 vaccine candidate administered in a prime-boost regimen. We found that ADVAX DNA prime followed by MVA boost induced significantly more peripheral CD8+ TSCM cells and higher levels of CD8+ T cell-mediated inhibition of replication of different HIV-1 clades as compared to MVA alone and placebo. These findings are novel and provide encouraging evidence to demonstrate the induction of TSCM and cytotoxic immune responses by a subtype C HIV-1 prophylactic vaccine administered using a prime-boost strategy.

Publication types

  • Clinical Trial, Phase I
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • AIDS Vaccines / administration & dosage
  • AIDS Vaccines / immunology*
  • Antiviral Agents / administration & dosage
  • Female
  • HIV Infections / immunology*
  • HIV Infections / prevention & control
  • HIV Infections / virology
  • HIV-1 / classification
  • HIV-1 / immunology*
  • Humans
  • Immunologic Memory / drug effects
  • Immunologic Memory / immunology*
  • Male
  • Stem Cells / drug effects
  • Stem Cells / immunology*
  • T-Lymphocyte Subsets / drug effects
  • T-Lymphocyte Subsets / immunology*
  • Vaccination
  • Virus Replication / drug effects
  • Virus Replication / immunology*
  • Volunteers

Substances

  • AIDS Vaccines
  • Antiviral Agents