In recent years, a variety of stem cells types have shown their potential for enhancing stroke recovery. In this study we compared therapeutic effects of three different types of human stem cells–human mesenchymal stem cells (hMSCs), induced pluripotent stem cell-derived progenitor cells (iNPCs), directly reprogrammed neural progenitor cells from human bone marrow MSCs (dr NPCs)–in treatment of ischemic stroke in rats.
Male Wistar rats 24h after 90 minutes MCAO were transplanted intra-arterial with saline (n=15) or different stem cells types (5x105 in 1 ml): MSCs isolated from human placenta (n=15), NPCs differentiated from iPS (n=10) and NPCs directly reprogrammed from human bone marrow MSCs (n=10) without genetic engineering techniques. For evaluation of therapeutic effects and infarct volume behavioral test and 7T-MRI and were performed at 1d, 7d, 14d after MCAO (before histology). 
The improvement of neurological deficit already after 7d were observed after transplantation of iNPCs, drNPC and MCSs. Reduction of stroke volume were observed after administration of iNPCs, drNPC only. Despite prominent therapeutic effects drNPC have great advantage – preparation protocol without requirement of viral integration. Transplantation of MSCs resulted in the best reduction of vasogenic edema and increased of survival rate, together with good functional recovery. All stem cells types were capable to migrate through the blood–brain barrier.

A comparative study of mesenchymal stem cell, iPS-derived neural progenitor cells and directly reprogrammed neural progenitor cells in treatment of ischemic stroke in rats