MSCs for graft-versus-host disease

Clinical graft-versus-host disease (GVHD) is a severe inflammatory condition and the main immune complication of allogeneic hematopoietic cell transplantation (HCT). While most patients respond favorably to standard treatment interventions, others do not. Thus, GVHD remains the principal limitation to the wider application of HCT. Even with dramatic increases in our understanding of the patho- biology of GVHD over the last half century, true progress in clinical care for individuals with GVHD has been limited. Recently, the unexpected ability of cultured mesenchymal stromal cells (MSCs) to modulate immune responses has captured considerable scientific and clinical interest because of their potential to limit immune injury and to repair tissues. Diverse non-hematopoietic cell types present in bone marrow, collectively termed stromal cells, provide a conceptually novel and practically elegant opportunity for anti-GVHD therapy. Here, we summarize the MSC experience most relevant to GVHD therapy and the reasons that MSCs hold the promise of fulfilling a major unmet need in the management of clinical GVHD.