The specific recognition by macrophages of CD8+,CD45RO+ T cells undergoing apoptosis: a mechanism for T cell clearance during resolution of viral infections

J Exp Med. 1994 Nov 1;180(5):1943-7. doi: 10.1084/jem.180.5.1943.

Abstract

During viral infections, CD8+,CD45RO+ T populations expand. These primed cells express abundant levels of cytoplasmic granules that contain perforin and TIA-1. Recent work has suggested that the majority of this CD8+ population downregulates Bcl-2 protein expression and is destined to undergo apoptosis. In this study we have investigated the elimination of these apoptotic CD8+ T cells by both human monocyte-derived and murine bone marrow macrophages. We have found that these phagocytes recognize and ingest both apoptotic CD8+ and CD4+ T cells using an alpha v beta 3 (vitronectin receptor)/CD36/thrombospondin recognition system, with the same receptors being used in the recognition of apoptotic neutrophils. These data provide new evidence for a mechanism that enables the clearance of greatly increased populations of CD8+ effector cells which are found during viral infections. This enables cellular homeostasis to occur in the host upon resolution of viral diseases in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Apoptosis*
  • CD8-Positive T-Lymphocytes / immunology*
  • Homeostasis
  • Humans
  • Leukocyte Common Antigens / analysis*
  • Macrophages / immunology*
  • Membrane Glycoproteins / analysis
  • Membrane Proteins*
  • Mice
  • Molecular Sequence Data
  • Perforin
  • Phagocytosis*
  • Poly(A)-Binding Proteins
  • Pore Forming Cytotoxic Proteins
  • Proteins*
  • RNA-Binding Proteins / analysis
  • T-Cell Intracellular Antigen-1
  • Virus Diseases / immunology*

Substances

  • Membrane Glycoproteins
  • Membrane Proteins
  • Poly(A)-Binding Proteins
  • Pore Forming Cytotoxic Proteins
  • Proteins
  • RNA-Binding Proteins
  • T-Cell Intracellular Antigen-1
  • TIA1 protein, human
  • Tia1 protein, mouse
  • Perforin
  • Leukocyte Common Antigens