HIV-1 efficient entry in inner foreskin is mediated by elevated CCL5/RANTES that recruits T cells and fuels conjugate formation with Langerhans cells

PLoS Pathog. 2011 Jun;7(6):e1002100. doi: 10.1371/journal.ppat.1002100. Epub 2011 Jun 30.

Abstract

Male circumcision reduces acquisition of HIV-1 by 60%. Hence, the foreskin is an HIV-1 entry portal during sexual transmission. We recently reported that efficient HIV-1 transmission occurs following 1 h of polarized exposure of the inner, but not outer, foreskin to HIV-1-infected cells, but not to cell-free virus. At this early time point, Langerhans cells (LCs) and T-cells within the inner foreskin epidermis are the first cells targeted by the virus. To gain in-depth insight into the molecular mechanisms governing inner foreskin HIV-1 entry, foreskin explants were inoculated with HIV-1-infeceted cells for 4 h. The chemokine/cytokine milieu secreted by the foreskin tissue, and resulting modifications in density and spatial distribution of T-cells and LCs, were then investigated. Our studies show that in the inner foreskin, inoculation with HIV-1-infected cells induces increased CCL5/RANTES (1.63-fold) and decreased CCL20/MIP-3-alpha (0.62-fold) secretion. Elevated CCL5/RANTES mediates recruitment of T-cells from the dermis into the epidermis, which is blocked by a neutralizing CCL5/RANTES Ab. In parallel, HIV-1-infected cells mediate a bi-phasic modification in the spatial distribution of epidermal LCs: attraction to the apical surface at 1 h, followed by migration back towards the basement membrane later on at 4 h, in correlation with reduced CCL20/MIP-3-alpha at this time point. T-cell recruitment fuels the continuous formation of LC-T-cell conjugates, permitting the transfer of HIV-1 captured by LCs. Together, these results reveal that HIV-1 induces a dynamic process of immune cells relocation in the inner foreskin that is associated with specific chemokines secretion, which favors efficient HIV-1 entry at this site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Communication / immunology
  • Cell Communication / physiology
  • Cell Movement
  • Cells, Cultured
  • Chemokine CCL20 / biosynthesis
  • Chemokine CCL5 / biosynthesis*
  • Chemokine CCL5 / immunology
  • Circumcision, Male
  • Foreskin / immunology
  • Foreskin / virology*
  • HIV Infections / immunology*
  • HIV Infections / transmission
  • HIV Infections / virology
  • HIV-1 / physiology*
  • Humans
  • Langerhans Cells / immunology*
  • Langerhans Cells / metabolism
  • Langerhans Cells / virology
  • Lymphocyte Activation
  • Male
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / virology
  • Virus Internalization*

Substances

  • CCL20 protein, human
  • CCL5 protein, human
  • Chemokine CCL20
  • Chemokine CCL5