Distinct APC subtypes drive spatially segregated CD4+ and CD8+ T-cell effector activity during skin infection with HSV-1

PLoS Pathog. 2014 Aug 14;10(8):e1004303. doi: 10.1371/journal.ppat.1004303. eCollection 2014 Aug.

Abstract

Efficient infection control requires potent T-cell responses at sites of pathogen replication. However, the regulation of T-cell effector function in situ remains poorly understood. Here, we show key differences in the regulation of effector activity between CD4+ and CD8+ T-cells during skin infection with HSV-1. IFN-γ-producing CD4+ T cells disseminated widely throughout the skin and draining lymph nodes (LN), clearly exceeding the epithelial distribution of infectious virus. By contrast, IFN-γ-producing CD8+ T cells were only found within the infected epidermal layer of the skin and associated hair follicles. Mechanistically, while various subsets of lymphoid- and skin-derived dendritic cells (DC) elicited IFN-γ production by CD4+ T cells, CD8+ T cells responded exclusively to infected epidermal cells directly presenting viral antigen. Notably, uninfected cross-presenting DCs from both skin and LNs failed to trigger IFN-γ production by CD8+ T-cells. Thus, we describe a previously unappreciated complexity in the regulation of CD4+ and CD8+ T-cell effector activity that is subset-specific, microanatomically distinct and involves largely non-overlapping types of antigen-presenting cells (APC).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adoptive Transfer
  • Animals
  • Antigen-Presenting Cells / immunology*
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Disease Models, Animal
  • Flow Cytometry
  • Fluorescent Antibody Technique
  • Herpes Simplex / immunology*
  • Herpesvirus 1, Human / immunology
  • Lymphocyte Activation / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Microscopy, Confocal
  • Skin Diseases, Infectious / immunology*

Grant support

The work was funded by grant (APP628423 and APP1059514) and fellowship support from the National Health and Medical Research Council Australia (NHMRC)and the Australian Research Council (ARC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.