Cxcl12 also known as stromal cell-derived factor 1 isoform alpha. This protein acts as a positive regulator of monocyte migration and a negative regulator of monocyte adhesion via the LYN kinase. It stimulates migration of monocytes and T-lymphocytes through its receptors, CXCR4 and ACKR3, and decreases monocyte adherence to surfaces coated with ICAM-1, a ligand for beta-2 integrins. This protein inhibits CXCR4-mediated infection by T-cell line-adapted HIV-1. Cxcl12 protein plays a protective role after myocardial infarction. It induces down-regulation and internalization of ACKR3 expressed in various cells. Recombinant mouse Cxcl12, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques