Secreted monkey Programmed Cell Death 1 (PD-1)-Fc fusion protein, also known as CD279, PDCD1, and SLEB2, GenBank Accession No. NM_001284136.1, a.a. 25-167, fused at the C-terminus to the Fc portion of human IgG1 with a C-terminal Avitag™, expressed in a HEK293 cell expression system. MW = 42.6 kDa. Note: this protein runs at an apparent higher molecular weight due to glycosylation. Biotinylation was confirmed to be >90%.