For example, SDF-1/CXCR4 plays roles in immune [34], hematopoietic [35], brain development [36], angiogenesis [37,38], HIV-1 infection [39], autoimmune diseases [34,40], cancer [41,42], inflammation [43] and other pathological processes [44]. The gene discussed is CXCR4; the disease is autoimmune disease.