Description: The 122 monoclonal antibody reacts with mouse B7-DC, also known as PD-L2. B7-DC, a recently identified member of the B7 family, has a predicted molecular weight of approximately 25 kDa and belongs to the Ig superfamily. The mouse B7-DC has a short cytoplasmic tail (4aa). B7-DC is primarily expressed by subpopulations of dendritic cells and monocytes/macrophages in the mouse. Although B7-DC has structural and sequence similarities to the B7 family, it does not bind CD28/CTLA-4, rather it is a ligand for PD-1. The interactions between PD-1 and B7-DC/PD-L2 have been reported to be involved in costimulation or suppression of T cell proliferation depending on state of cellular activation. 122 has been demonstrated to block binding of TY25 (Cat. No. 14-5986), another mAb specific for mouse B7-DC.