An effective vaccination approach augments anti-HIV systemic and vaginal immunity in mice with decreased HIV-1 susceptible α4β7high CD4+ T cells

Curr HIV Res. 2013 Jan;11(1):56-66.

Abstract

HIV-1 preferentially infects activated CD4(+) T cells expressing α4β7 integrin and conventional vaccination approaches non-selectively induce immune responses including α4β7(high) CD4(+) T cells, suggesting that current candidate AIDS vaccines may produce more target cells for HIV-1 and paradoxically enhance HIV-1 infection. Thus it remains a challenge to selectively induce robust anti-HIV immunity without the unwanted HIV-1 susceptible α4β77(high) CD4(+)+ T cells. Here we describe a vaccination strategy that targets ALDH1a2, a retinoic acid producing enzyme in dendritic cells (DCs). Silencing ALDH1a2 in DCs enhanced the maturation and production of proinflammatory cytokines of DCs and promoted Th1/Th2 differentiation while suppressing Treg. ALDH1a2-silenced DCs effectively downregulated the expression of guthoming receptors α4β77 and CCR9 on activated T and B lymphocytes. Consequently, intranasal immunization of a lentiviral vaccine encoding ALDH1a2 shRNA and HIV-1 gp140 redirected gp140-specific mucosal T cell and antibody responses from the gut to the vaginal tract, while dramatically enhancing systemic gp140-specific immune responses. We further demonstrated that silencing ALDH1a2 in human DCs resulted in downregulation of β7 expression on activated autologous CD4(+) T cells. Hence this study provides a unique and effective strategy to induce α4β7(low) anti-HIV immune responses.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aldehyde Dehydrogenase 1 Family
  • Animals
  • B-Lymphocytes / immunology
  • B-Lymphocytes / metabolism
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / metabolism
  • Cytokines / metabolism
  • Dendritic Cells / metabolism
  • Disease Models, Animal
  • Down-Regulation
  • Female
  • Gene Silencing
  • HIV Infections / immunology*
  • HIV Infections / metabolism
  • HIV Infections / prevention & control
  • HIV-1 / immunology*
  • Integrins / metabolism
  • Mice
  • Mice, Inbred BALB C
  • Retinal Dehydrogenase / physiology*
  • Vaccination / methods*
  • Vagina / immunology*

Substances

  • Cytokines
  • Integrins
  • integrin alpha4beta7
  • Aldehyde Dehydrogenase 1 Family
  • ALDH1A2 protein, human
  • Retinal Dehydrogenase