Mouse secreted Programmed Cell Death 1 (PD-1)-Fc fusion protein, also known as CD279, PDCD1, and SLEB2, GenBank Accession No. NM_008798, a.a. 25-167, with a C-terminal Avi-His-tag, expressed in a HEK293 cell expression system. MW = 19 kDa. This protein runs at an apparent higher molecular weight due to glycosylation.