title: Establishment of human induced pluripotent stem cell lines from normal fibroblast TIG-1.
abstract: Normal human cells have a replicative life span and therefore senesce. Usually, normal human cell strains are differentiated cells and reach a terminally differentiated state after a number of cell divisions. At present, definitive differences are not known between replicative senescence and terminal differentiation. TIG-1 is a human fibroblast strain established from fetal lung and has been used extensively in studies of cellular senescence, and numerous data were accumulated at the molecular level. Recently, a method for generating induced pluripotent stem cells (iPSCs) was developed. Using the method, we introduced four reprogramming genes to TIG-1 fibroblasts and succeeded in isolating colonies that had embryonic stem cell (ESC)-like morphologies. They showed alkaline phosphatase activity and expressed ESC markers, as shown by immunostaining of OCT4, SOX2, SSEA4, and TRA-1-81 as well as reverse-transcription polymerase chain reaction (RT-PCR) for OCT4 and NANOG transcripts. Thus, we succeeded in establishing iPSC clones from TIG-1. The iPSC clones could differentiate to cells originated from all three germ-cell layers, as shown by RT-PCR, for messenger RNA (mRNA) expression of α-fetoprotein (endoderm), MSX1 (mesoderm) and microtubule-associated protein 2 (ectoderm), and by immunostaining for α-fetoprotein (endoderm), α-smooth muscle actin (mesoderm), and β-III-tubulin (ectoderm). The iPSCs formed teratoma containing the structures developed from all three germ-cell layers in severe combined immune-deficiency mice. Thus, by comparing the aging process of parental TIG-1 cells and the differentiation process of iPSC-derived fibrocytes to fibroblasts, we can reveal the exact differences in processes between senescence and terminal differentiation.
authors.affiliation: Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences at Kagawa, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa, 769-2193, Japan. t-kuma-k@kph.bunri-u.ac.jp
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kumazaki
authors.forename: Sayaka
authors.initials: S
authors.lastname: Kurata
authors.forename: Taira
authors.initials: T
authors.lastname: Matsuo
authors.forename: Youji
authors.initials: Y
authors.lastname: Mitsui
authors.forename: Tomoko
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D016922:Cellular Senescence; D005347:Fibroblasts / Q000166:cytology*; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D039904:Pluripotent Stem Cells / Q000166:cytology* / Q000473:pathology; D013724:Teratoma / Q000473:pathology