Direct in vivo application of induced pluripotent stem cells is feasible and can be safe

作者:Xiang, Meng; Lu, Meng; Quan, Jing; Xu, Ming; Meng, Dan; Cui, Anfeng; Li, Ning; Liu, Yingying; Lu, Peng; Kang, Xueling; Wang, Xiaokai; Sun, Ning; Zhao, Meng; Liang, Qiujuan; Le, Lili; Wang, Xinhong; Zhang, Jianyi; Chen, Sifeng*
来源:Theranostics, 2019, 9(1): 290-310.
DOI:10.7150/thno.28671

摘要

Increasing evidence suggests the consensus that direct in vivo application of induced pluripotent stem cells (iPSCs) is infeasible may not be true. @@@ Methods: Teratoma formation and fate were examined in 53 normal and disease conditions involving brain, lung, liver, kidney, islet, skin, hind limb, and arteries. @@@ Results: Using classic teratoma generation assays, which require iPSCs to be congregated and confined, all mouse, human, and individualized autologous monkey iPSCs tested formed teratoma, while iPSC-derived cells did not. Intravenously or topically-disseminated iPSCs did not form teratomas with doses up to 2.5x10(8) iPSCs/kg and observation times up to 18 months, regardless of host tissue type; autologous, syngeneic, or immune-deficient host animals; presence or absence of disease; disease type; iPSC induction method; commercial or self-induced iPSCs; mouse, human, or monkey iPSCs; frequency of delivery; and sex. Matrigel-confined, but not PBS-suspended, syngeneic iPSCs delivered into the peritoneal cavity or renal capsule formed teratomas. Intravenously administered iPSCs were therapeutic with a dose as low as 5x10(6)/kg and some iPSCs differentiated into somatic cells in injured organs. Disseminated iPSCs trafficked into injured tissue and survived significantly longer in injured than uninjured organs. In disease-free animals, no intravenously administered cell differentiated into an unwanted long-lasting cell or survived as a quiescent stem cell. In coculture, the stem cell medium and dominant cell-type status were critical for iPSCs to form cell masses. @@@ Conclusion: Teratoma can be easily and completely avoided by disseminating the cells. Direct in vivo iPSC application is feasible and can be safe.