Origins of peripheral B cells in IL-7 receptor-deficient mice

Mol Immunol. 2006 Feb;43(4):326-34. doi: 10.1016/j.molimm.2005.02.010.


The interleukin 7 (IL-7) signaling pathway is critical for early lymphoid differentiation. We found dramatic perturbations in fetal liver B cell development and confirmed a complete absence of developing B cells in the adult bone marrow in mice lacking the IL-7 receptor alpha (IL-7Ralpha) gene. We show that peripheral B-2 and B-1 cell populations are deficient in IL-7Ralpha-/- mice. B-2 follicular cell and peritoneal B-1 cell percentages are reduced, while B-2 marginal zone cell percentages are increased. A comparison of bone marrow and splenic populations at different ages revealed that the splenic B cell populations seen in adult IL-7Ralpha-/- mice first appear during neonatal development. We have measured N-nucleotide addition at the joints of V(D)J rearrangements in splenic B cells and have used it as a somatic marker to define and separate bone marrow-derived B cells from fetal liver-derived B cells. B cells isolated from the bone marrow and spleen of adult and neonatal IL-7Ralpha-deficient mice harbor high levels of N-nucleotide additions similar to those found in equivalent wild-type B cell populations. We conclude that the majority of splenic B cells in IL-7Ralpha-deficient mice originate from the bone marrow and not the fetal liver.

Publication types

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

MeSH terms

  • Age Factors
  • Animals
  • Animals, Newborn
  • B-Lymphocytes / cytology*
  • Bone Marrow / embryology
  • Bone Marrow / growth & development
  • Bone Marrow Cells / cytology
  • Cell Differentiation
  • Cell Lineage*
  • DNA Nucleotidylexotransferase / metabolism
  • Gene Rearrangement, B-Lymphocyte
  • Kinetics
  • Liver / cytology
  • Liver / embryology
  • Liver / growth & development
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptors, Interleukin-7 / deficiency*
  • Receptors, Interleukin-7 / genetics
  • Sequence Alignment
  • Spleen / cytology*
  • VDJ Exons


  • Receptors, Interleukin-7
  • interleukin-7 receptor, alpha chain
  • DNA Nucleotidylexotransferase