Immunoglobulin gene rearrangement in B cell deficient mice generated by targeted deletion of the JH locus

Int Immunol. 1993 Jun;5(6):647-56. doi: 10.1093/intimm/5.6.647.


B lymphocyte differentiation is characterized by an ordered series of Ig gene assembly and expression events. In the majority of normal B cells, assembly and expression of Ig heavy (H) chain genes precedes that of light (L) chain genes. To determine the role of the Ig heavy chain protein in B cell development and L chain gene rearrangement, we have generated mice that cannot assemble Ig H chain genes as a result of targeted deletion of the JH gene segments in embryonic stem cells. Mice homozygous for this deletion are devoid of slg+ B cells in the bone marrow and periphery. B cell differentiation in these mice is blocked at the large, CD43+ precursor stage. However, these precursor B cells do assemble kappa L chain genes at a low level in the absence of mu H chain proteins. These data demonstrate that rearrangement and expression of the mu H chain gene is not absolutely required for kappa L chain gene rearrangement in vivo. Expression of mu chains may facilitate either efficient L chain gene rearrangement or the survival of cells that have rearranged light chain genes by promoting the differentiation of large, CD43+ to small, CD43- pre-B cells.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • B-Lymphocytes / cytology
  • B-Lymphocytes / immunology
  • Base Sequence
  • DNA / genetics
  • Gene Rearrangement, B-Lymphocyte*
  • Gene Rearrangement, B-Lymphocyte, Light Chain
  • Hematopoietic Stem Cells / immunology
  • Homozygote
  • Immunoglobulin Heavy Chains / genetics
  • Immunoglobulin Joining Region / genetics
  • Mice
  • Molecular Sequence Data
  • Recombination, Genetic
  • Sequence Deletion


  • Immunoglobulin Heavy Chains
  • Immunoglobulin Joining Region
  • DNA