Impaired B cell development and function in mice with a targeted disruption of the homeobox gene Hex

Proc Natl Acad Sci U S A. 2003 Jan 21;100(2):556-61. doi: 10.1073/pnas.0236979100. Epub 2003 Jan 8.

Abstract

Hex is a homeobox gene that is expressed in all stages of B cell development except plasma cells. We studied lymphocyte development in the absence of Hex by using the RAG1-deficient blastocyst complementation system because homozygous disruption of Hex is embryonic lethal. Hex(-/-);RAG1(-/-) chimeric mice had severely reduced numbers of mature B cells, pre-B cells, and CD5(+) B cells with a striking 15-fold increase in the percentage of B220(-)CD19(+) cells in the bone marrow. Hex(-/-);RAG1(-/-) chimeric mice failed to generate IgG antibodies to T cell-independent antigens, although their serum IgM levels and antibody responses to T cell-dependent antigens were intact. Therefore, Hex is necessary for B cell development and function and its absence results in a dramatic increase in B220(-)CD19(+) cells.

Publication types

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

MeSH terms

  • Animals
  • Antigens, CD19 / analysis
  • B-Lymphocytes / physiology*
  • Genes, Homeobox / physiology*
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / physiology
  • Immunoglobulin G / biosynthesis
  • Immunoglobulin M / biosynthesis
  • Leukocyte Common Antigens / analysis
  • Lymphopoiesis*
  • Mice
  • Mice, Inbred C57BL
  • Transcription Factors

Substances

  • Antigens, CD19
  • Hhex protein, mouse
  • Homeodomain Proteins
  • Immunoglobulin G
  • Immunoglobulin M
  • Transcription Factors
  • RAG-1 protein
  • Leukocyte Common Antigens