Purity: > 90% by SDS - PAGE Format: Liquid. In Phosphate Buffered Saline (pH 7.4) containing 10% glycerol.. VTCN1, also known as v-set domain-containing T-cell activation inhibitor 1 isoform 1, is a member of the costimulatory B7 family. It has been found to be widely expressed in many kinds of tumor tissues and to play an important part in tumor progression and poor prognosis. It serves a critical role in the negative regulation of T cell-mediated antitumor immune responses. It facilitates proliferation of esophageal squamous cell carcinoma cells through promoting interleukin-6/signal transducer and activator of transcription 3 pathway activation. Recombinant human VTCN1, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.