Schulte R J, Campbell M A, Fischer W H, Sefton B M
Molecular Biology and Virology Laboratory, Salk Institute, San Diego, CA 92186.
Science. 1992 Nov 6;258(5084):1001-4. doi: 10.1126/science.1279802.
Ligation of the antigen receptor on B cells induces the rapid phosphorylation of tyrosine on a number of cellular proteins. A monoclonal antibody that recognized a tyrosine-phosphorylated cell surface protein that was present in activated B cells was generated. Amino acid sequence analysis showed that this 140-kilodalton protein was CD22, a B cell-specific cell surface glycoprotein and putative extracellular ligand of the protein tyrosine phosphatase CD45. Tyrosine phosphorylation of CD22 may be important in B cell signal transduction, possibly through regulation of the adhesiveness of activated B cells.
