SDF-1 signaling: a promising target in rheumatic diseases

Introduction: Stromal cell-derived factor 1 (SDF-1) is a potent chemoattractant cytokine with various biological functions such as stem cell mobilization, inflammatory cell infiltration and angiogenesis. Therefore, it has also been implicated in several pathological processes, from ischemic conditions to cancer. Remarkably, SDF-1 and its receptors, CXCR4 and CXCR7, are also present in joint tissues, where they play a role in the pathogenesis of rheumatoid arthritis (RA) and osteoarthritis (OA). Areas covered: This review summarizes the physiological and pathological role of SDF-1 signaling and its involvement in RA and OA. That includes synovial inflammation, bone erosion, cartilage degradation and increased bone turnover. Although this cytokine could play different roles in these rheumatic diseases, specific and differentiated therapeutic targets in each process can be identified. Current therapeutic strategies to block SDF-1 signaling in several diseases and their possible use in rheumatic diseases are also discussed. Expert opinion: Emerging drugs that block CXCR4 or CXCR7 in different disorders may represent promising therapies for rheumatic disease via inhibition of key pathological events involved in the progression of RA and OA.