Syndecan-1 precursor, also known as SDC1, is a transmembrane heparin sulphate proteoglycan which is made up of one core protein and five glycosaminoglycan. SDC1 is expected to play a role in cell adhesion. It is expressed on the surface of pre-B cells and plasma cells but is absent from mature B cells. It is a selective marker for B cell lymphoblastic leukemia and lymphoplasmocytoid leukemia. Recombinant human SDC1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.