title: Identification and in vitro derivation of spermatogonia in beagle testis.
abstract: BACKGROUND
  In vitro culture of spermatogonial stem cells (SSCs) is important for exploration of SSCs self-renewal, differentiation, and manipulation. There are several reports on rodent SSC cultures; however, data on SSC cultures in domestic animals are limited. To provide basic scientific information on canine SSC cultures, we report canine testes development, and the development of spermatogonia-derived colonies (SDCs) for in vitro cultures.
  
  
  RESULTS
  Testes from 2-, 3-, and 12-month-old beagles were used for histology, immunohistochemistry, in vitro culture, immunocytochemistry, and PCR. Protein gene product 9.5 (PGP9.5)-positive spermatogonia, both single and paired, were found to be abundant in the testes of 2-month-old beagles. stempro-34 and Dulbecco's modified Eagle medium with 5% fetal bovine serum provided as useful substrates for culture of SDCs, and fibroblast growth factor (FGF) played a key role in colony formation. Colonies were positive for alkaline phosphatase and anti-PGP9.5 staining. The early spermatogonia and stem cell markers such as octamer binding protein 4 (Oct4), Nanog homeobox (Nanog), promyelocytic leukemia zinc finger (PLZF), PGP9.5, and GDNF family receptor alpha-1 (GFRα-1) were expressed in the colonies at higher levels than in the testis tissue.
  
  
  CONCLUSIONS
  Testes of the 2-month-old beagles had abundant single and paired spermatogonia, which can be used for derivation of SDCs, and FGF was important for colony formation.
authors.affiliation: Department of Animal and Food Bioscience, RIBH, Konkuk University, Chung-ju, Korea.
authors.forename: Kyung Hoon
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Animal and Food Bioscience, RIBH, Konkuk University, Chung-ju, Korea.
authors.forename: Ran
authors.initials: R
authors.lastname: Lee
authors.affiliation: Department of Animal and Food Bioscience, RIBH, Konkuk University, Chung-ju, Korea.
authors.forename: Won Young
authors.initials: WY
authors.lastname: Lee
authors.affiliation: Animal Biotechnology Division, National Institute of Animal Science, Suwon, Korea.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Animal Biotechnology Division, National Institute of Animal Science, Suwon, Korea.
authors.forename: Hak Jae
authors.initials: HJ
authors.lastname: Chung
authors.affiliation: Department of Animal Biotechnology, Konkuk University, Seoul, Korea.
authors.forename: Jin Hoi
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Animal Science, Chungbuk National University, Choung-ju, Korea.
authors.forename: Nam Hyung
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of Veterinary Science, Chungbuk National University, Choung-ju, Korea.
authors.forename: Suk Hwa
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Departmemt of Biomedical Science, CHA University, Seongnam, Republic of Korea.
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Animal and Food Bioscience, RIBH, Konkuk University, Chung-ju, Korea.
authors.forename: Hyuk
authors.initials: H
authors.lastname: Song
mesh_terms: D053687:Adult Stem Cells / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D002455:Cell Division; D004285:Dogs; D005346:Fibroblast Growth Factors / Q000378:metabolism; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D050814:Octamer Transcription Factor-3 / Q000378:metabolism; D013093:Spermatogonia / Q000166:cytology* / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D050814:Octamer Transcription Factor-3; D014157:Transcription Factors; D005346:Fibroblast Growth Factors