Human secreted Programmed Cell Death 1_x000D_(PD-1)-Fc fusion protein, also known as_x000D_CD279, PDCD1, and SLEB2, GenBank_x000D_Accession No. NM_014143, a.a. 25-167_x000D_with a K78A mutation, fused at the Cterminus_x000D_with the Fc portion of human IgG1,_x000D_and C-terminal AviTag™, expressed in a_x000D_HEK293 cell expression system and_x000D_enzymatically biotin-labeled using AviTag™_x000D_technology. MW = 44.5 kDa. This protein_x000D_runs at a higher MW by SDS-PAGE due to_x000D_glycosylation.