10.1371/journal.pone.0192884 Hiroyuki Sanjo Hiroyuki Sanjo Mitsuru Komeya Mitsuru Komeya Takuya Sato Takuya Sato Takeru Abe Takeru Abe Kumiko Katagiri Kumiko Katagiri Hiroyuki Yamanaka Hiroyuki Yamanaka Yoko Ino Yoko Ino Noriaki Arakawa Noriaki Arakawa Hisashi Hirano Hisashi Hirano Tatsuma Yao Tatsuma Yao Yuta Asayama Yuta Asayama Akio Matsuhisa Akio Matsuhisa Masahiro Yao Masahiro Yao Takehiko Ogawa Takehiko Ogawa <i>In vitro</i> mouse spermatogenesis with an organ culture method in chemically defined medium Public Library of Science 2018 Knockout serum replacement KSR FSH mouse spermatogenesis testis organ culture organ culture method round spermatid production LH RA medium organ culture conditions 2 days postpartum MEM CDM BSA 2018-02-12 18:45:26 Dataset https://plos.figshare.com/articles/dataset/_i_In_vitro_i_mouse_spermatogenesis_with_an_organ_culture_method_in_chemically_defined_medium/5880724 <div><p>We previously reported the successful induction and completion of mouse spermatogenesis by culturing neonatal testis tissues. The culture medium consisted of α-minimum essential medium (α-MEM), supplemented with Knockout serum replacement (KSR) or AlbuMAX, neither of which were defined chemically. In this study, we formulated a chemically defined medium (CDM) that can induce mouse spermatogenesis under organ culture conditions. It was found that bovine serum albumin (BSA) purified through three different procedures had different effects on spermatogenesis. We also confirmed that retinoic acid (RA) played crucial roles in the onset of spermatogonial differentiation and meiotic initiation. The added lipids exhibited weak promoting effects on spermatogenesis. Lastly, luteinizing hormone (LH), follicle stimulating hormone (FSH), triiodothyronine (T3), and testosterone (T) combined together promoted spermatogenesis until round spermatid production. The CDM, however, was not able to produce elongated spermatids. It was also unable to induce spermatogenesis from the very early neonatal period, before 2 days postpartum, leaving certain factors necessary for spermatogenic induction in mice unidentified. Nonetheless, the present study provided important basic information on testis organ culture and spermatogenesis <i>in vitro</i>.</p></div>