Regulation of activated CD4+ T cells by NK cells via the Qa-1-NKG2A inhibitory pathway

Immunity. 2007 May;26(5):593-604. doi: 10.1016/j.immuni.2007.03.017.

Abstract

The ability of natural-killer cells to regulate adaptive immunity is not well understood. Here we define an interaction between the class Ib major histocompatibility complex (MHC) molecule Qa-1-Qdm on activated T cells responsible for adaptive immunity and CD94-NKG2A inhibitory receptors expressed by natural-killer cells by using Qa-1-deficient and Qa-1 knockin mice containing a point mutation that selectively abolishes Qa-1-Qdm binding to CD94-NKG2A receptors. The Qa-1-NKG2A interaction protected activated CD4+ T cells from lysis by a subset of NKG2A+ NK cells and was essential for T cell expansion and development of immunologic memory. Antibody-dependent blockade of this Qa-1-NKG2A interaction resulted in potent NK-dependent elimination of activated autoreactive T cells and amelioration of experimental autoimmune encephalomyelitis. These findings extend the functional reach of the NK system to include regulation of adaptive T cell responses and suggest a new clinical strategy for elimination of antigen-activated T cells in the context of autoimmune disease and transplantation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Marrow / immunology
  • Bone Marrow / metabolism
  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / metabolism
  • Cell Proliferation
  • Cells, Cultured
  • Chimerin Proteins / genetics
  • Chimerin Proteins / immunology
  • Chimerin Proteins / metabolism
  • DNA-Binding Proteins / deficiency
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Encephalomyelitis, Autoimmune, Experimental / genetics
  • Encephalomyelitis, Autoimmune, Experimental / immunology
  • Encephalomyelitis, Autoimmune, Experimental / metabolism
  • Encephalomyelitis, Autoimmune, Experimental / pathology
  • Gene Expression Regulation / immunology*
  • Genetic Predisposition to Disease
  • Histocompatibility Antigens Class I / genetics
  • Histocompatibility Antigens Class I / metabolism*
  • Immunologic Memory / immunology
  • Interferon-gamma / biosynthesis
  • Killer Cells, Natural / cytology
  • Killer Cells, Natural / immunology*
  • Killer Cells, Natural / metabolism
  • Lentivirus / genetics
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Knockout
  • NK Cell Lectin-Like Receptor Subfamily C
  • NK Cell Lectin-Like Receptor Subfamily D / genetics
  • NK Cell Lectin-Like Receptor Subfamily D / metabolism
  • Phenotype
  • Receptors, Immunologic / genetics
  • Receptors, Immunologic / metabolism*
  • Receptors, Natural Killer Cell
  • Signal Transduction / immunology*

Substances

  • Chimerin Proteins
  • DNA-Binding Proteins
  • Histocompatibility Antigens Class I
  • Klrc1 protein, mouse
  • NK Cell Lectin-Like Receptor Subfamily C
  • NK Cell Lectin-Like Receptor Subfamily D
  • Q surface antigens
  • Rag2 protein, mouse
  • Receptors, Immunologic
  • Receptors, Natural Killer Cell
  • Interferon-gamma