Scientific article

Differentially regulated expression and function of CD22 in activated B-1 and B-2 lymphocytes

Published inThe Journal of immunology, vol. 168, no. 12, p. 6078-6083
Publication date2002

CD22 is a B cell-restricted transmembrane protein that apparently controls signal transduction thresholds initiated through the B cell Ag receptor (BCR) in response to Ag. However, it is still poorly understood how the expression of CD22 is regulated in B cells after their activation. Here we show that the expression levels of CD22 in conventional B-2 cells are markedly down-regulated after cross-linking of BCR with anti-IgM mAb but are up-regulated after stimulation with LPS, anti-CD40 mAb, or IL-4. In contrast, treatment with anti-IgM mAb barely modulated the expression levels of CD22 in CD5(+) B-1 cells, consistent with a weak Ca(2+) response in anti-IgM-treated CD5(+) B-1 cells. Moreover, in CD22-deficient mice, anti-IgM treatment did not trigger enhanced Ca(2+) influx in CD5(+) B-1 cells, unlike CD22-deficient splenic B-2 cells, suggesting a relatively limited role of CD22 in BCR signaling in B-1 cells. In contrast, CD22 levels were markedly down-regulated on wild-type B-1 cells in response to LPS or unmethylated CpG-containing oligodeoxynucleotides. These data indicate that the expression and function of CD22 are differentially regulated in B-1 and conventional B-2 cells, which are apparently implicated in innate and adaptive immunity, respectively.

  • Adjuvants, Immunologic/pharmacology
  • Animals
  • Antibodies, Anti-Idiotypic/pharmacology
  • Antibodies, Monoclonal/pharmacology
  • Antigens, CD/ biosynthesis/metabolism/physiology
  • Antigens, CD22
  • Antigens, CD40/immunology
  • Antigens, Differentiation, B-Lymphocyte/ biosynthesis/metabolism/physiology
  • B-Lymphocyte Subsets/ immunology/ metabolism
  • Calcium/metabolism
  • Calcium Signaling/immunology
  • Cell Adhesion Molecules
  • Cells, Cultured
  • CpG Islands/immunology
  • Down-Regulation/immunology
  • Immunoglobulin M/immunology
  • Interleukin-4/pharmacology
  • Lectins
  • Lipopolysaccharides/pharmacology
  • Lymphocyte Activation/ immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Mutant Strains
  • Oligodeoxyribonucleotides/pharmacology
  • Peritoneum/cytology/immunology/metabolism
  • Spleen/cytology/immunology
  • Up-Regulation/immunology
Affiliation Not a UNIGE publication
Citation (ISO format)
LAJAUNIAS, Frédéric et al. Differentially regulated expression and function of CD22 in activated B-1 and B-2 lymphocytes. In: The Journal of immunology, 2002, vol. 168, n° 12, p. 6078–6083.
Updates (1)
ISSN of the journal0022-1767

Technical informations

Creation08/27/2010 1:35:15 PM
First validation08/27/2010 1:35:15 PM
Update time03/14/2023 4:04:07 PM
Status update03/14/2023 4:04:07 PM
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