B cell progenitors are arrested in maturation but have intact VDJ recombination in the absence of Ig-alpha and Ig-beta

J Immunol. 2002 Jul 15;169(2):865-72. doi: 10.4049/jimmunol.169.2.865.

Abstract

Ig-alpha and Ig-beta mediate surface expression and signaling of diverse B cell receptor complexes on precursor, immature, and mature B cells. Their expression begins before that of the Ig chains in early progenitor B cells. In this study, we describe the generation of Ig-alpha-deficient mice and their comparative analysis to mice deficient for Ig-beta, the membrane-IgM, and recombination-activating gene 2 to determine the requirement of Ig-alpha and Ig-beta in survival and differentiation of pro-B cells. We find that in the absence of Ig-alpha, B cell development does not progress beyond the progenitor stage, similar to what is observed in humans lacking this molecule. However, neither in Ig-alpha- nor in Ig-beta-deficient mice are pro-B cells impaired in V(D)J recombination, in the expression of intracellular Ig micro-chains, or in surviving in the bone marrow microenvironment. Finally, Ig-alpha and Ig-beta are not redundant in their putative function, as pro-B cells from Ig-alpha and Ig-beta double-deficient mice are similar to those from single-deficient animals in every aspect analyzed.

Publication types

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

MeSH terms

  • Animals
  • Antibody Diversity / genetics
  • Antigens, CD / biosynthesis
  • Antigens, CD / genetics*
  • Antigens, CD / physiology
  • B-Lymphocyte Subsets / immunology*
  • B-Lymphocyte Subsets / metabolism*
  • B-Lymphocyte Subsets / pathology
  • CD79 Antigens
  • Cell Differentiation / genetics*
  • Cell Differentiation / immunology*
  • Cell Survival / genetics
  • Cell Survival / immunology
  • Crosses, Genetic
  • DNA Nucleotidyltransferases / deficiency
  • DNA Nucleotidyltransferases / genetics
  • DNA-Binding Proteins / deficiency
  • DNA-Binding Proteins / genetics
  • Gene Rearrangement, B-Lymphocyte, Heavy Chain*
  • Immunoglobulin Heavy Chains / biosynthesis
  • Immunoglobulin Heavy Chains / genetics
  • Immunoglobulin Joining Region / biosynthesis
  • Immunoglobulin Joining Region / genetics
  • Immunoglobulin Variable Region / biosynthesis
  • Immunoglobulin Variable Region / genetics
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptors, Antigen, B-Cell / biosynthesis
  • Receptors, Antigen, B-Cell / deficiency
  • Receptors, Antigen, B-Cell / genetics*
  • Receptors, Antigen, B-Cell / physiology
  • Stem Cells / immunology*
  • Stem Cells / metabolism*
  • Stem Cells / pathology
  • VDJ Recombinases

Substances

  • Antigens, CD
  • CD79 Antigens
  • Cd79a protein, mouse
  • Cd79b protein, mouse
  • DNA-Binding Proteins
  • Immunoglobulin Heavy Chains
  • Immunoglobulin Joining Region
  • Immunoglobulin Variable Region
  • Rag2 protein, mouse
  • Receptors, Antigen, B-Cell
  • V(D)J recombination activating protein 2
  • DNA Nucleotidyltransferases
  • VDJ Recombinases