Development of innate CD4+ and CD8+ T cells in Itk-deficient mice is regulated by distinct pathways

J Immunol. 2014 Jul 15;193(2):688-99. doi: 10.4049/jimmunol.1302059. Epub 2014 Jun 18.

Abstract

T cell development in the thymus produces multiple lineages of cells, including innate T cells such as γδ TCR(+) cells, invariant NKT cells, mucosal-associated invariant T cells, and H2-M3-specific cells. Although innate cells are generally a minor subset of thymocytes, in several strains of mice harboring mutations in T cell signaling proteins or transcriptional regulators, conventional CD8(+) T cells develop as innate cells with characteristics of memory T cells. Thus, in Itk-deficient mice, mature CD4(-)CD8(+) (CD8 single-positive [SP]) thymocytes express high levels of the transcription factor eomesodermin (Eomes) and are dependent on IL-4 being produced in the thymic environment by a poorly characterized subset of CD4(+) thymocytes expressing the transcriptional regulator promyelocytic leukemia zinc finger. In this study, we show that a sizeable proportion of mature CD4(+)CD8(-) (CD4SP) thymocytes in itk(-/-) mice also develop as innate Eomes-expressing T cells. These cells are dependent on MHC class II and IL-4 signaling for their development, indicating that they are conventional CD4(+) T cells that have been converted to an innate phenotype. Surprisingly, neither CD4SP nor CD8SP innate Eomes(+) thymocytes in itk(-/-) or SLP-76(Y145F) mice are dependent on γδ T cells for their development. Instead, we find that the predominant population of Eomes(+) innate itk(-/-) CD4SP thymocytes is largely absent in mice lacking CD1d-specific invariant NKT cells, with no effect on innate itk(-/-) CD8SP thymocytes. In contrast, both subsets of innate Eomes(+)itk(-/-) T cells require the presence of a novel promyelocytic leukemia zinc finger-expressing, SLAM family receptor adapter protein-dependent thymocyte population that is essential for the conversion of conventional CD4(+) and CD8(+) T cells into innate T cells with a memory phenotype.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antigens, CD1d / immunology
  • Antigens, CD1d / metabolism
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / metabolism
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / metabolism
  • Cell Differentiation / genetics
  • Cell Differentiation / immunology
  • Cell Proliferation
  • Flow Cytometry
  • Interleukin-15 / deficiency
  • Interleukin-15 / genetics
  • Interleukin-15 / immunology
  • Interleukin-4 / immunology
  • Interleukin-4 / metabolism
  • Kruppel-Like Transcription Factors / immunology
  • Kruppel-Like Transcription Factors / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Natural Killer T-Cells / immunology
  • Natural Killer T-Cells / metabolism
  • Promyelocytic Leukemia Zinc Finger Protein
  • Protein-Tyrosine Kinases / deficiency
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / immunology*
  • Rats
  • Receptors, Antigen, T-Cell, alpha-beta / immunology
  • Receptors, Antigen, T-Cell, alpha-beta / metabolism
  • Receptors, Antigen, T-Cell, gamma-delta / immunology
  • Receptors, Antigen, T-Cell, gamma-delta / metabolism
  • Signal Transduction / genetics
  • Signal Transduction / immunology*
  • T-Box Domain Proteins / immunology
  • T-Box Domain Proteins / metabolism
  • Thymocytes / immunology
  • Thymocytes / metabolism

Substances

  • Antigens, CD1d
  • Eomes protein, mouse
  • Interleukin-15
  • Kruppel-Like Transcription Factors
  • Promyelocytic Leukemia Zinc Finger Protein
  • Receptors, Antigen, T-Cell, alpha-beta
  • Receptors, Antigen, T-Cell, gamma-delta
  • T-Box Domain Proteins
  • Zbtb16 protein, mouse
  • Interleukin-4
  • Protein-Tyrosine Kinases
  • emt protein-tyrosine kinase