SDF-1 is small cytokine belonging to the chemokine family that is officially designated Chemokine (CX-C motif) ligand 12 (CXCL12). SDF-1 is strongly chemotactic for lymphocytes and works by its receptor CXCR4. The SDF-1+CXCR4 complex plays a significant role in the creation of metastases of neoplasms and as a response to cytostatic treatment. Identification of this complex may be a useful prognostic factor in the therapy of many types of carcinoma. Recombinant human SDF-1, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography.