title: Efforts to create an artificial testis: culture systems of male germ cells under biochemical conditions resembling the seminiferous tubular biochemical environment.
abstract: Induction of meiotic and post-meiotic alterations of male germ cells in vitro has been the target of several research efforts since 1960. However, to date, the establishment of an ideal culture system in which spermatogonial stem cells can be maintained and directed to proliferate and undergo meiosis and complete spermiogenesis does not exist. This is attributed to the difficulties concerning the isolation and purification of defined subpopulations of germ cells and the establishment of male germ cell lines. In addition, there is no adequate knowledge regarding the optimal biochemical conditions that promote the survival and differentiation of germ cells in long-term cultures. This review focuses on the methodologies that have been proved sufficient to achieve differentiation of cultured male germ cells. Furthermore, the factors regulating spermatogenesis and the technical prerequisites to achieve differentiation of cultured male germ cells are described. Finally, the role of in vitro cultures of immature diploid germ cells in the therapeutic management of men negative for haploid cells in their testes and the subsequent potential genetic and epigenetic risks are discussed.
authors.affiliation: Laboratory for Molecular Urology and Genetics of Human Reproduction, Department of Urology, Ioannina University School of Medicine, Ioannina, Greece. akrosnin@hotmail.com
authors.forename: N
authors.initials: N
authors.lastname: Sofikitis
authors.forename: E
authors.initials: E
authors.lastname: Pappas
authors.forename: A
authors.initials: A
authors.lastname: Kawatani
authors.forename: D
authors.initials: D
authors.lastname: Baltogiannis
authors.forename: D
authors.initials: D
authors.lastname: Loutradis
authors.forename: N
authors.initials: N
authors.lastname: Kanakas
authors.forename: D
authors.initials: D
authors.lastname: Giannakis
authors.forename: F
authors.initials: F
authors.lastname: Dimitriadis
authors.forename: K
authors.initials: K
authors.lastname: Tsoukanelis
authors.forename: I
authors.initials: I
authors.lastname: Georgiou
authors.forename: G
authors.initials: G
authors.lastname: Makrydimas
authors.forename: Y
authors.initials: Y
authors.lastname: Mio
authors.forename: V
authors.initials: V
authors.lastname: Tarlatzis
authors.forename: M
authors.initials: M
authors.lastname: Melekos
authors.forename: I
authors.initials: I
authors.lastname: Miyagawa
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation / Q000502:physiology; D018920:Coculture Techniques; D006801:Humans; D008297:Male; D008540:Meiosis / Q000502:physiology; D009865:Oocytes / Q000502:physiology; D012671:Seminiferous Tubules / Q000502:physiology*; D012708:Sertoli Cells / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D013091:Spermatogenesis / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology*