SPSB2 is a suppressor of cytokine signaling (SOCS) family member, and it belongs to the subfamily of proteins containing a central SPRY (repeats in splA and RyR) domain and a C-terminal SOCS box. This protein is present in a gene-rich cluster on chromosome 12p13 in the vicinity of the CD4 antigen and triosephosphate isomerase genes. Recombinant human SPSB2 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.