Inositol 1,4,5-trisphosphate 3-kinase B is a negative regulator of BCR signaling that controls B cell selection and tolerance induction

J Immunol. 2009 Apr 15;182(8):4696-704. doi: 10.4049/jimmunol.0802850.

Abstract

Inositol 1,4,5-trisphosphate 3-kinase B (or Itpkb) converts inositol 1,4,5-trisphosphate to inositol 1,3,4,5-tetrakisphosphate upon Ag receptor activation and controls the fate and function of lymphocytes. To determine the role of Itpkb in B cell tolerance, Itpkb(-/-) mice were crossed to transgenic mice that express a BCR specific for hen egg lysozyme (IgHEL). B cells from Itpkb(-/-) IgHEL mice possess an anergic phenotype, hypoproliferate in response to cognate Ag, and yet they exhibit enhanced Ag-induced calcium signaling. In IgHEL transgenic mice that also express soluble HEL, lack of Itpkb converts anergy induction to deletion. These data establish Itpkb as a negative regulator of BCR signaling that controls the fate of developing B cells and tolerance induction.

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / metabolism
  • B-Lymphocytes / cytology
  • B-Lymphocytes / drug effects
  • B-Lymphocytes / enzymology*
  • B-Lymphocytes / immunology*
  • Bcl-2-Like Protein 11
  • Bone Marrow / immunology
  • Calcium / metabolism
  • Cell Differentiation / immunology
  • Cells, Cultured
  • Gene Deletion
  • Immune Tolerance / immunology*
  • Inositol Phosphates / pharmacology
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Phosphotransferases (Alcohol Group Acceptor) / deficiency
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Protein Kinase Inhibitors / pharmacology
  • Proto-Oncogene Proteins / metabolism
  • Receptors, Antigen, B-Cell / immunology*
  • Signal Transduction / immunology*

Substances

  • Apoptosis Regulatory Proteins
  • Bcl-2-Like Protein 11
  • Bcl2l11 protein, mouse
  • Inositol Phosphates
  • Membrane Proteins
  • Protein Kinase Inhibitors
  • Proto-Oncogene Proteins
  • Receptors, Antigen, B-Cell
  • inositol-1,3,4,5-tetrakisphosphate
  • Phosphotransferases (Alcohol Group Acceptor)
  • Inositol 1,4,5-trisphosphate 3-kinase
  • Calcium