immunoglobulin complex B cell receptor complex An immunoglobulin complex that is present in the plasma membrane of B cells and that in its canonical form is composed of two identical immunoglobulin heavy chains and two identical immunoglobulin light chains and a signaling subunit, a heterodimer of the Ig-alpha and Ig-beta proteins. B cell receptor accessory molecule complex B lymphocyte receptor complex B-cell receptor complex B-lymphocyte receptor complex BCR complex GO:0019815 GO:0042570 Note that an immunoglobulin complex has the function of antigen binding if a suitable antigen is available. antibody cellular_component go.owl immunoglobulin complex, membrane bound obi.owl plasma membrane protein complex plasma membrane receptor complex