Human secreted GITR, also known as Glucocorticoid-induced TNFR-Related Protein, Tumor Necrosis Factor Receptor Superfamily member 18, TNFRSF18, Activation-Inducible TNFR Family Receptor, AITR, and CD357, GenBank Accession No. NM_004195, a.a. 26-161 expressed in a HEK293 cell expression system, fused at the C-terminus to the Fc portion of human IgG1, and enzymatically biotin-labeled using Avi-tag™ technology. MW = 43 kDa (monomer). This protein runs at a higher MW by SDS-PAGE due to glycosylation.