Skin resident memory CD8+ T cells are phenotypically and functionally distinct from circulating populations and lack immediate cytotoxic function. Academic Article uri icon

Overview

abstract

  • The in-depth understanding of skin resident memory CD8+ T lymphocytes (TRM ) may help to uncover strategies for their manipulation during disease. We investigated isolated TRM from healthy human skin, which expressed the residence marker CD69, and compared them to circulating CD8+ T cell populations from the same donors. There were significantly increased proportions of CD8+ CD45RA- CD27- T cells in the skin that expressed low levels of killer cell lectin-like receptor G1 (KLRG1), CD57, perforin and granzyme B. The CD8+ TRM in skin were therefore phenotypically distinct from circulating CD8+ CD45RA- CD27- T cells that expressed high levels of all these molecules. Nevertheless, the activation of CD8+ TRM with T cell receptor (TCR)/CD28 or interleukin (IL)-2 or IL-15 in vitro induced the expression of granzyme B. Blocking signalling through the inhibitory receptor programmed cell death 1 (PD)-1 further boosted granzyme B expression. A unique feature of some CD8+ TRM cells was their ability to secrete high levels of tumour necrosis factor (TNF)-α and IL-2, a cytokine combination that was not seen frequently in circulating CD8+ T cells. The cutaneous CD8+ TRM are therefore diverse, and appear to be phenotypically and functionally distinct from circulating cells. Indeed, the surface receptors used to distinguish differentiation stages of blood T cells cannot be applied to T cells in the skin. Furthermore, the function of cutaneous TRM appears to be stringently controlled by environmental signals in situ.

publication date

  • September 12, 2018

Research

keywords

  • Immunologic Memory
  • Skin
  • T-Lymphocytes, Cytotoxic

Identity

PubMed Central ID

  • PMC6156810

Scopus Document Identifier

  • 85053394969

Digital Object Identifier (DOI)

  • 10.1016/j.jaci.2017.10.032

PubMed ID

  • 30030847

Additional Document Info

volume

  • 194

issue

  • 1