Intravenous allogeneic umbilical cord blood-derived mesenchymal stem cell therapy in recessive dystrophic epidermolysis bullosa patients

BACKGROUND. Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable disease that causes severe mucocutaneous fragility due to mutations in COL7A1 (encoding type VII collagen [C7]). In this phase I/IIa trial, we evaluated the safety and possible clinical efficacy of intravenous infusion of allogeneic human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in patients with RDEB. METHODS. Four adult and two pediatric patients with RDEB were treated with 3 intravenous injections of hUCB-MSCs (1 x 10(6) to 3 x 10(6) cells/kg) every 2 weeks and followed up for 8-24 months after treatment. The primary endpoint was safety. Secondary endpoints related to efficacy included clinical parameters, such as disease severity score, wound assessment, itch and pain score, and quality of life. C7 expression levels and inflammatory infiltrates in the skin, as well as serum levels of inflammatory markers and neuropeptides, were also assessed. RESULTS. Intravenous hUCB-MSC infusions were well tolerated, without serious adverse events. Improvements in the Birmingham Epidermolysis Bullosa Severity Score, body surface area involvement, blister counts, pain, pruritus, and quality of life were observed with maximal effects at 56-112 days after treatment. hUCB-MSC administration induced M2 macrophage polarization and reduced mast cell infiltration in RDEB skin. Serum levels of substance P were decreased after therapy. Increased C7 expression was observed at the dermoepidermal junction in 1 of 6 patients at day 56. CONCLUSION. To the best of our knowledge, this is the first clinical trial of systemic administration of allogeneic hUCB-MSCs in patients with RDEB, demonstrating safety and transient clinical benefits.

Automated summary

This study evaluated the safety and potential clinical efficacy of intravenous infusion of allogeneic human umbilical cord blood-derived mesenchymal stem cells in patients with Recessive Dystrophic Epidermolysis Bullosa (RDEB). The results showed that the treatment was well tolerated and led to transient clinical benefits, including improvements in wound conditions, pain, itch, and quality of life. Inflammatory skin conditions and C7 expression also showed some improvement after treatment.