P2 purinoceptors in the immune system

Ciba Found Symp. 1996;198:290-302; discussion 302-5. doi: 10.1002/9780470514900.ch17.

Abstract

Immune cells express plasma membrane receptors for extracellular nucleotides. Both G protein-linked metabotropic and channel-forming ionotropic receptors have been described, although no P2 receptor subtype has been cloned from the immune system thus far. Metabotropic receptors have been described in human B but not T lymphocytes; they have not been found in mouse B and T cells. Ionotropic receptors seem to be ubiquitously expressed in the immune system; however, their functional properties, if not their pharmacology, appear to be different in different immune cells. Human T normal and B leukaemic lymphocytes, human macrophages, mouse B and T lymphocytes, mouse microglial and macrophage cells, and rat mast cells express ionotropic receptors that recognize ATP4- as the preferred ligand, are activated by 3'-O-(4-benzoyl)benzoyl ATP and inhibited by oxidized ATP. The pharmacological profile of ionotropic receptors expressed by different immune cells is similar, but their permeability properties may be different: the pore formed by receptors expressed by macrophages, microglial cells and mast cells is typically permeable to charged molecules of molecular mass up to 900 Da; on the contrary, that expressed by lymphocytes has a molecular cut-off of 200-300 Da. The ionotrpic receptor of immune cells is modulated by inflammatory cytokines (e.g. interleukin [IL]-2 and gamma-interferon) and is also modulated during monocyte to macrophage differentiation. Transient stimulation of the ionotropic receptor of macrophages and microglial cells elicits IL-1 beta release. Sustained activation leads to cell death, either by necrosis or apoptosis, depending on the given cell type.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cell Death / immunology
  • Humans
  • Immune System / immunology
  • Receptors, Purinergic P2 / immunology*
  • Receptors, Purinergic P2X7
  • Receptors, Purinergic P2Y2

Substances

  • P2RX7 protein, human
  • P2RY2 protein, human
  • P2rx7 protein, mouse
  • P2rx7 protein, rat
  • P2ry2 protein, mouse
  • P2ry2 protein, rat
  • Receptors, Purinergic P2
  • Receptors, Purinergic P2X7
  • Receptors, Purinergic P2Y2