Central memory CD8+ T cells become CD69+ tissue-residents during viral skin infection independent of CD62L-mediated lymph node surveillance

PLoS Pathog. 2019 Mar 15;15(3):e1007633. doi: 10.1371/journal.ppat.1007633. eCollection 2019 Mar.

Abstract

Memory CD8+ T cells in the circulation rapidly infiltrate non-lymphoid tissues following infection and provide protective immunity in an antigen-specific manner. However, the subsequent fate of memory CD8+ T cells after entering non-lymphoid tissues such as the skin during a secondary infection is largely unknown. Furthermore, because expression of CD62L is often used to identify the central memory (TCM) CD8+ T cell subset, uncoupling the physical requirement for CD62L-mediated lymph node homing versus other functional attributes of TCM CD8+ T cells remains unresolved. Here, we show that in contrast to naïve CD8+ T cells, memory CD8+ T cells traffic into the skin independent of CD62L-mediated lymph node re-activation and provide robust protective immunity against Vaccinia virus (VacV) infection. TCM, but not effector memory (TEM), CD8+ T cells differentiated into functional CD69+/CD103- tissue residents following viral clearance, which was also dependent on local recognition of antigen in the skin microenvironment. Finally, we found that memory CD8+ T cells expressed granzyme B after trafficking into the skin and utilized cytolysis to provide protective immunity against VacV infection. Collectively, these findings demonstrate that TCM CD8+ T cells become cytolytic following rapid infiltration of the skin to protect against viral infection and subsequently differentiate into functional CD69+ tissue-residents.

Publication types

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

MeSH terms

  • Animals
  • Antigens, CD / metabolism
  • Antigens, CD / physiology
  • Antigens, Differentiation, T-Lymphocyte / metabolism
  • Antigens, Differentiation, T-Lymphocyte / physiology
  • CD8-Positive T-Lymphocytes / metabolism*
  • CD8-Positive T-Lymphocytes / virology
  • Female
  • Immunologic Memory / physiology*
  • L-Selectin / metabolism
  • Lectins, C-Type / metabolism
  • Lectins, C-Type / physiology
  • Lymph Nodes
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Skin / immunology*
  • Skin / virology
  • T-Lymphocyte Subsets / metabolism
  • T-Lymphocyte Subsets / physiology
  • Vaccinia virus / immunology
  • Vaccinia virus / pathogenicity

Substances

  • Antigens, CD
  • Antigens, Differentiation, T-Lymphocyte
  • CD69 antigen
  • Lectins, C-Type
  • L-Selectin