Cytoplasmic Ig alpha serine/threonines fine-tune Ig alpha tyrosine phosphorylation and limit bone marrow plasma cell formation

J Immunol. 2011 Sep 15;187(6):2853-8. doi: 10.4049/jimmunol.1101143. Epub 2011 Aug 12.

Abstract

Igα serine 191 and 197 and threonine 203, which are located in proximity of the Igα ITAM, dampen Igα ITAM tyrosine phosphorylation. In this study, we show that mice with targeted mutations of Igα S191, 197, and T203 displayed elevated serum IgG2c and IgG2b concentrations and had elevated numbers of IgG2c- and IgG2b-secreting cells in the bone marrow. BCR-induced Igα tyrosine phosphorylation was slightly increased in splenic B cells. Our results suggest that Igα serine/threonines limit formation of IgG2c- and IgG2b-secreting bone marrow plasma cells, possibly by fine-tuning Igα tyrosine-mediated BCR signaling.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bone Marrow Cells / cytology*
  • Bone Marrow Cells / immunology
  • Bone Marrow Cells / metabolism
  • Cell Differentiation
  • Cell Separation
  • Cytoplasm / chemistry
  • Cytoplasm / immunology
  • Cytoplasm / metabolism
  • Enzyme-Linked Immunosorbent Assay
  • Flow Cytometry
  • Immunoblotting
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Mutation / genetics
  • Mutation / immunology*
  • Phosphorylation
  • Plasma Cells / cytology*
  • Plasma Cells / immunology
  • Plasma Cells / metabolism
  • Receptors, Antigen, B-Cell / chemistry*
  • Receptors, Antigen, B-Cell / genetics
  • Receptors, Antigen, B-Cell / immunology*
  • Serine / chemistry
  • Serine / immunology
  • Signal Transduction / genetics
  • Signal Transduction / immunology
  • Threonine / chemistry
  • Threonine / immunology
  • Tyrosine / metabolism

Substances

  • Receptors, Antigen, B-Cell
  • Threonine
  • Tyrosine
  • Serine