Mesenchymal Stem Cells for Treatment of Refractory Chronic Graft-Versus-Host Disease.

Refractory extensive chronic graft-versus-host disease (GVHD) after allogeneic stem-cell transplantation (SCT) is associated with high mortality [Margolis J., SeminOncol 2000].However, conventional therapies including steroids are often unsuccessful in those patients with multiorgan involvement and are associated with significant therapy-related complications and poorly life quality. Mesenchymal stem cells (MSCs) have immunomodulatory effects [Tse WT et al., Transplantation 2003; Spees JI et al.,Proc Natl Acad Sci USA 2003]. Recently MSCs have been given intravenously to treat seven steroid resistant acute GVHD patients and one patient with chronic GVHD. MSCs effects in chronic GVHD is rarely known, although this successfully experience suggests that MSCs have been well tolerated and had a powerful immunosuppressive effects on acute GVHD. [Katarina Le Blanc et al., Lancet 2004; Olle Ringden., Transplantation 2006 ]. Here, we present our experience of using MSCs for treatment of Thirteen patients with refractory chronic GVHD. Between May 2005 and March 2007, thirteen patients (8 male, 5female) with hematological malignancies with a median age of 26(range:15 to 40) years who had received peripheral stem cells from sibling donors. All patients developed steroid resistant or extensive chronic GVHD, with progressive involvement of the skin(13), liver(10), oral mucosa(12),ocular glands(12), and thrombocytopenia (1) when the immunosuppressive agents were taped after five to twenty-four months. The MSC dose was median 1.0 ×10⁶ cells/kg body weight of the recipient. In all, thirteen patients had at least received one dose, seven patients received more than two doses. MSC donors were in seven cases HLA-identical siblings, six unrelated mismatched donors. No side-effects were seen after MSCs infusions. All patients have responded after follow-up of the median time 15 months. One patient with moderate cGVHD had a complete responses, and discontinued all of the immunosuppressive agents without relapse more than 18.4 months after MSC infusion. Three moderate and two patients with severe chronic GVHD improved to mild degree, and six severe turned to moderate degree. Complete resolution was seen in gut(2/3), liver(5/10), skin(5/13), oral(6/12) and eye(2/12). One patient responded in skin, liver, oral mucose and eye, but developed in lung (bronchiolitis obliterans, BO) score of 2 which are considered severe chronic GVHD. Mean follow-up periods was 27m (rang: 14 to48m), Leukemia free survival(LFS)rate were 85%(11/13), and the overall survival (OS)rate were 92.3%(12/13). Our experience suggests that MSC infusion is a safe and effective adjunct therapy for refractory extensive chronic GVHD with resistance to conventional therapy. But more prospective, controlled studies with MSCs for treatment of GVHD should be performanced to evaluate this new treatment exactly.