Regulation of lymphocyte activation by the cell-surface molecule CD22.

Accessory molecules play an important role in the regulation of lymphocyte activation mediated by the B-cell antigen receptor (BCR). CD22 is one such accessory molecule expressed on B-lineage cells. Here, Che-Leung Law and colleagues review current knowledge on the structure-function relationship between CD22 and the BCR, discuss the role of CD22 as a cell-adhesion molecule and suggest models for potential in vivo functions of CD22.