title: Episomal Induced Pluripotent Stem Cells Promote Functional Recovery of Transected Murine Peripheral Nerve.
abstract: Traumatic peripheral nerve neurotmesis occurs frequently and functional recovery is often slow and impaired. Induced pluripotent stem cells (iPSCs) have shown much promise in recent years due to its regenerative properties similar to that of embryonic stem cells. However, the potential of iPSCs in promoting the functional recovery of a transected peripheral nerve is largely unknown. This study is the first to investigate in vivo effects of episomal iPSCs (EiPSCs) on peripheral nerve regeneration in a murine sciatic nerve transection model. Episomal iPSCs refer to iPSCs that are generated via Oct3/4-Klf4-Sox2 plasmid reprogramming instead of the conventional viral insertion techniques. It represents a relatively safer form of iPSC production without permanent transgene integration which may raise questions regarding risks of genomic mutation. A minimal number of EiPSCs were added directly to the transected nerve. Functional recovery of the EiPSC group was significantly improved compared to the negative control group when assessed via serial five-toe spread measurement and gait analysis of ankle angles. EiPSC promotion of nerve regeneration was also evident on stereographic analysis of axon density, myelin thickness, and axonal cross-sectional surface area. Most importantly, the results observed in EiPSCs are similar to that of the embryonic stem cell group. A roughly ten-fold increase in neurotrophin-3 levels was seen in EiPSCs which could have contributed to peripheral nerve regeneration and recovery. No abnormal masses or adverse effects were noted with EiPSC administration after one year of follow-up. We have hence shown that functional recovery of the transected peripheral nerve can be improved with the use of EiPSC therapy, which holds promise for the future of nerve regeneration.
authors.affiliation: Vascularized Composite Allotransplantation Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan.|Division of Surgery and Interventional Science, University College London, London, United Kingdom.
authors.forename: Charles Yuen Yung
authors.initials: CY
authors.lastname: Loh
authors.affiliation: Vascularized Composite Allotransplantation Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Aline Yen Ling
authors.initials: AY
authors.lastname: Wang
authors.affiliation: Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Huang-Kai
authors.initials: HK
authors.lastname: Kao
authors.affiliation: Vascularized Composite Allotransplantation Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Esteban
authors.initials: E
authors.lastname: Cardona
authors.affiliation: Vascularized Composite Allotransplantation Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Sheng-Hao
authors.initials: SH
authors.lastname: Chuang
authors.affiliation: Vascularized Composite Allotransplantation Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.|College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Fu-Chan
authors.identifier: http://orcid.org/0000-0003-1609-1237
authors.initials: FC
authors.lastname: Wei
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology; D065150:Cellular Reprogramming; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D005684:Gait; D007150:Immunohistochemistry; D057026:Induced Pluripotent Stem Cells / Q000166:cytology / Q000378:metabolism / Q000637:transplantation*; D016547:Kinesins / Q000235:genetics / Q000378:metabolism; D000090062:Kruppel-Like Factor 4; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D009414:Nerve Growth Factors / Q000378:metabolism; D009416:Nerve Regeneration; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism; D020127:Recovery of Function; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism; D012584:Sciatic Nerve / Q000502:physiology* / Q000601:surgery
chemical_list: C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D009414:Nerve Growth Factors; D050814:Octamer Transcription Factor-3; D055748:SOXB1 Transcription Factors; C518911:neurotropin 3, mouse; C089655:Kif4 protein, mouse; D016547:Kinesins