1. BCR complex BCR(mlg): VH, VL----Ag mature B cells: mIgm and mIgd Function: specifically recognizes antigen ga/gB(CD79aCD79b ) heterodimer cytoplasmic domains contain ITAM Function: 1. transfers the signals that lead to b cell activation 2. transports the Ig1. BCR complex • BCR (mIg)：VH,VL----Ag mature B cells: mIgM and mIgD. Function: specifically recognizes antigen. • Ig/Ig (CD79a/CD79b): heterodimer cytoplasmic domains contain ITAM. Function: 1. transfers the signals that lead to B cell activation. 2. transports the Ig