MSC therapy of inborn errors

Abstract

Mesenchymal stromal cells are ideally suited as cell therapy for inborn errors. While there are several potential mechanisms of therapeutic activity, in all studies yet, MSCs seem to exert their effects through the release of soluble mediators. This vast secretome, together with the capacity to modulate gene expression of the MSC therapeutic product through optimal selection of tissue source and ex vivo expansion protocols, suggests the potential to develop broadly applicable therapy for a wide array of disorders. However, the clinical experience to date is limited, most likely due to our unrealized historic view that MSCs were stem cells that could regenerate tissue. A pilot study in children with metachromatic leukodystrophy showed that MSCs may be able to increase nerve conduction velocity, suggesting that the cells may be stimulating remyelination of peripheral nerves. In osteogenesis imperfecta, MSCs unambiguously stimulate growth of the children who exhibit the characteristic severe growth deficiency. As our understanding of the fundamental biology of MSCs continues to improve, enthusiasm to assess MSCs in patients with inborn errors is also growing. The coming decade promises a swell of clinical trials and likely important breakthroughs.