title: Brief report: impaired cell reprogramming in nonhomologous end joining deficient cells.
abstract: Although there is an increasing interest in defining the role of DNA damage response mechanisms in cell reprogramming, the relevance of proteins participating in nonhomologous end joining (NHEJ), a major mechanism of DNA double-strand breaks repair, in this process remains to be investigated. Herein, we present data related to the reprogramming of primary mouse embryonic fibroblasts (MEF) from severe combined immunodeficient (Scid) mice defective in DNA-PKcs, a key protein for NHEJ. Reduced numbers of induced pluripotent stem cell (iPSC) colonies were generated from Scid cells using reprogramming lentiviral vectors (LV), being the reprogramming efficiency fourfold to sevenfold lower than that observed in wt cells. Moreover, these Scid iPSC-like clones were prematurely lost or differentiated spontaneously. While the Scid mutation neither reduce the proliferation rate nor the transduction efficacy of fibroblasts transduced with reprogramming LV, both the expression of SA-β-Gal and of P16/INK(4a) senescence markers were highly increased in Scid versus wt MEFs during the reprogramming process, accounting for the reduced reprogramming efficacy of Scid MEFs. The use of improved Sleeping Beauty transposon/transposase systems allowed us, however, to isolate DNA-PKcs-deficient iPSCs which preserved their parental genotype and hypersensitivity to ionizing radiation. This new disease-specific iPSC model would be useful to understand the physiological consequences of the DNA-PKcs mutation during development and would help to improve current cell and gene therapy strategies for the disease.
authors: Division of Hematopoietic Innovative Therapies (HIT), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)/Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBER-ER), Madrid, Spain.
authors: F Javier
authors: FJ
authors: Molina-Estevez
authors: M Luz
authors: ML
authors: Lozano
authors: Susana
authors: S
authors: Navarro
authors: Yaima
authors: Y
authors: Torres
authors: Ivana
authors: I
authors: Grabundzija
authors: Zoltan
authors: Z
authors: Ivics
authors: Enrique
authors: E
authors: Samper
authors: Juan A
authors: JA
authors: Bueren
authors: Guillermo
authors: G
authors: Guenechea
mesh_terms: D000818:Animals; D065150:Cellular Reprogramming / Q000235:genetics*; D059766:DNA End-Joining Repair; D057026:Induced Pluripotent Stem Cells / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D016513:Mice, SCID; D014162:Transfection
keywords: DNA-dependent protein kinase catalytic subunit; Immunodeficient mouse; Induced pluripotent stem cells; Nonhomologous end joining; Reprogramming; Severe combined immunodeficiency