title: Transgene excision has no impact on in vivo integration of human iPS derived neural precursors.
abstract: The derivation of induced human pluripotent stem cells (hiPS) has generated significant enthusiasm particularly for the prospects of cell-based therapy. But there are concerns about the suitability of iPS cells for in vivo applications due in part to the introduction of potentially oncogenic transcription factors via viral vectors. Recently developed lentiviral vectors allow the excision of viral reprogramming factors and the development of transgene-free iPS lines. However it is unclear if reprogramming strategy has an impact on the differentiation potential and the in vivo behavior of hiPS progeny. Here we subject viral factor-free, c-myc-free and conventionally reprogrammed four-factor human iPS lines to a further challenge, by analyzing their differentiation potential along the 3 neural lineages and over extended periods of time in vitro, as well as by interrogating their ability to respond to local environmental cues by grafting into the striatum. We demonstrate similar and efficient differentiation into neurons, astrocytes and oligodendrocytes among all hiPS and human ES line controls. Upon intracranial grafting in the normal rat (Sprague Dawley), precursors derived from all hiPS lines exhibited good survival and response to environmental cues by integrating into the subventricular zone, acquiring phenotypes typical of type A, B or C cells and migrating along the rostral migratory stream into the olfactory bulb. There was no teratoma or other tumor formation 12 weeks after grafting in any of the 26 animals used in the study. Thus neither factor excision nor persistence of c-myc impact the behavior of hiPS lines in vivo.
authors.affiliation: Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York, United States of America.
authors.forename: Tamara
authors.initials: T
authors.lastname: Major
authors.forename: Jayanthi
authors.initials: J
authors.lastname: Menon
authors.forename: Gordon
authors.initials: G
authors.lastname: Auyeung
authors.forename: Frank
authors.initials: F
authors.lastname: Soldner
authors.forename: Dirk
authors.initials: D
authors.lastname: Hockemeyer
authors.forename: Rudolf
authors.initials: R
authors.lastname: Jaenisch
authors.forename: Viviane
authors.initials: V
authors.lastname: Tabar
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation; D002465:Cell Movement; D002478:Cells, Cultured; D003342:Corpus Striatum / Q000601:surgery; D000089622:Doublecortin Domain Proteins; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D057026:Induced Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000032:analysis; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D009479:Neuropeptides / Q000032:analysis; D009836:Oligodendroglia / Q000166:cytology / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D033581:Stem Cell Transplantation / Q000379:methods*; D019076:Transgenes / Q000235:genetics; D014183:Transplantation, Heterologous; D014404:Tubulin / Q000032:analysis
chemical_list: D000089622:Doublecortin Domain Proteins; D005904:Glial Fibrillary Acidic Protein; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides; D014404:Tubulin