Dec 1, 1996

Characterization of the expression and gene promoter of CD22 in murine B cells

European Journal of Immunology
K B AnderssonE A Clark

Abstract

CD22 is a B cell-restricted surface molecule which may play an important role in interactions between B cells and other cells and in regulating signals through the B cell receptor (BCR) complex. Here we have examined whether the mouse is a suitable in vivo model for studying CD22 functions. In primary and secondary lymphoid organs of adult mice CD22 is on all mature B cells, including resting IgM+IgD+ B cells, IgG+ HSA(lo) memory B cells, syndecan+ plasma cells and CD5+ B cells, but it is not on immature IgM+IgD- B cells. Biochemical analysis revealed that murine CD22 is associated with the IgM receptor in some, but not all, CD22+ B leukemic and lymphoma cell lines; as with human CD22, murine CD22 is rapidly phosphorylated on tyrosine after ligation of the BCR. In the CD22- murine pro-B cell line, FEMCL, CD22 expression was inducible by treatment with phorbol 12-myristate 13-acetate. A genomic fragment of the cd22b allele containing 1.3 kb 5' of exon 1 was sequenced in order to identify potential DNA regulatory elements in the CD22 promoter region. Consensus sequences for transcription factor binding sites including PU.1, AP-1, AP-2, C/EBP and SP-1 were present, but no classical TATA elements or initiator motifs were evident at...Continue Reading

Mentioned in this Paper

JUN gene
JUND gene
CD22 antigen
T-Lymphocyte
Leukocyte Differentiation Antigens, Human
Mice, Inbred BALB C
Exons
Genome
Receptors, Antigen, B-Cell
Transcription Factor AP-2 Alpha

Related Feeds

B cell Differentiation

Depending on the signal received through the B cell receptor and other receptors, B cells differentiate into follicular or marginal zone B cells. Here is the latest research pertaining to this differentiation process.