4-1BB Soluble Receptor Recombinant Human also called Tumor necrosis factor receptor superfamily member 9 produced in E.Coli is a single, non-glycosylated polypeptide chain containing 167 amino acids, having a molecular mass of 17718 Dalton and containing the cysteine rich TNFR-like extracellular domain of 4-1BB Receptor. The 4-1BB Receptor is purified by proprietary chromatographic techniques.