Immediate cytotoxicity but not degranulation distinguishes effector and memory subsets of CD8+ T cells

J Exp Med. 2004 Apr 5;199(7):925-36. doi: 10.1084/jem.20031799. Epub 2004 Mar 29.

Abstract

CD8+ T cells play a central role in the resolution and containment of viral infections. A key effector function of CD8+ T cells is their cytolytic activity toward infected cells. Here, we studied the regulation of cytolytic activity in naive, effector, and central versus effector memory CD8+ T cells specific for the same glycoprotein-derived epitope of lymphocytic choriomeningitis virus. Our results show that the kinetics of degranulation, assessed by a novel flow cytometric based assay, were identical in effector and both subsets of memory CD8+ T cells, but absent in naive CD8+ T cells. However, immediate cytolytic activity was most pronounced in effector T cells, low in effector memory T cells, and absent in central memory T cells, correlating with the respective levels of cytolytic effector molecules present in lytic granules. These results indicate that an inherent program of degranulation is a feature of antigen-experienced cells as opposed to naive CD8+ T cells and that the ability of CD8+ T cells to induce target cell apoptosis/death is dependent on granule protein content rather than on the act of degranulation itself. Furthermore, these results provide a potential mechanism by which central memory CD8+ T cell-mediated death of antigen-presenting cells within the lymph node is avoided.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Viral
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Degranulation
  • Cytotoxicity, Immunologic*
  • Epitopes
  • Immunologic Memory
  • L-Selectin / metabolism
  • Lymphocytic choriomeningitis virus / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • T-Lymphocyte Subsets / immunology

Substances

  • Antigens, Viral
  • Epitopes
  • L-Selectin