title: Retracted article: In vitro derivation of mammalian germ cells from stem cells and their potential therapeutic application.
abstract: Pluripotent stem cells (PSCs) are a unique type of cells because they exhibit the characteristics of self-renewal and pluripotency. PSCs may be induced to differentiate into any cell type, even male and female germ cells, suggesting their potential as novel cell-based therapeutic treatment for infertility problems. Spermatogenesis is an intricate biological process that starts from self-renewal of spermatogonial stem cells (SSCs) and leads to differentiated haploid spermatozoa. Errors at any stage in spermatogenesis may result in male infertility. During the past decade, much progress has been made in the derivation of male germ cells from various types of progenitor stem cells. Currently, there are two main approaches for the derivation of functional germ cells from PSCs, either the induction of in vitro differentiation to produce haploid cell products, or combination of in vitro differentiation and in vivo transplantation. The production of mature and fertile spermatozoa from stem cells might provide an unlimited source of autologous gametes for treatment of male infertility. Here, we discuss the current state of the art regarding the differentiation potential of SSCs, embryonic stem cells, and induced pluripotent stem cells to produce functional male germ cells. We also discuss the possible use of livestock-derived PSCs as a novel option for animal reproduction and infertility treatment.
authors.affiliation: Saito Laboratory of Cell Technology, Yaita, Tochigi, 329-1571, Japan. saict@maple.ocn.ne.jp.|SPK Co., Ltd., Aizuwakamatsu, Fukushima, 965-0025, Japan. saict@maple.ocn.ne.jp.|College of Engineering, Nihon University, Koriyama, Fukushima, 963-8642, Japan. saict@maple.ocn.ne.jp.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Saito
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaoshiung Medical University, 100 Shin-Chuan 1st Road, Kaohsiung, 807, Taiwan.
authors.forename: Ying-Chu
authors.initials: YC
authors.lastname: Lin
authors.affiliation: College of Engineering, Nihon University, Koriyama, Fukushima, 963-8642, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Murayama
authors.affiliation: Cell Engineering Division, RIKEN BioResource Center, Tsukuba, 3050074, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Department of Biochemistry and Molecular Biology, Rutgers New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, 07101, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Eckner
authors.affiliation: Institute of Farm Animal Genetics, Friedrich-Löffler-Institut, Mariensee, 31535, Neustadt, Germany. heiner.niemann@fli.bund.de.
authors.forename: Heiner
authors.initials: H
authors.lastname: Niemann
authors.affiliation: Graduate Institute of Medicine, Center of Stem Cell Research, Center of Environmental Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd, San Ming District, Kaohsiung, 807, Taiwan. kazu@kmu.edu.tw.|Faculty of Science and Engineering, Tokushima Bunri University, Sanuki, 763-2193, Japan. kazu@kmu.edu.tw.|Department of Molecular Preventive Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan. kazu@kmu.edu.tw.
authors.forename: Kazunari K
authors.initials: KK
authors.lastname: Yokoyama
keywords: Animal reproduction; Embryonic stem cells; Gametes; Germ cells; Primordial germ cells; Spermatogonial stem cells; Sterility; Therapeutic use