title: Characterization, cryopreservation, and ablation of spermatogonial stem cells in adult rhesus macaques.
abstract: Spermatogonial stem cells (SSCs) are at the foundation of mammalian spermatogenesis. Whereas rare A(single) spermatogonia comprise the rodent SSC pool, primate spermatogenesis arises from more abundant A(dark) and A(pale) spermatogonia, and the identity of the stem cell is subject to debate. The fundamental differences between these models highlight the need to investigate the biology of primate SSCs, which have greater relevance to human physiology. The alkylating chemotherapeutic agent, busulfan, ablates spermatogenesis in rodents and causes infertility in humans. We treated adult rhesus macaques with busulfan to gain insights about its effects on SSCs and spermatogenesis. Busulfan treatment caused acute declines in testis volume and sperm counts, indicating a disruption of spermatogenesis. One year following high-dose busulfan treatment, sperm counts remained undetectable, and testes were depleted of germ cells. Similar to rodents, rhesus spermatogonia expressed markers of germ cells (VASA, DAZL) and stem/progenitor spermatogonia (PLZF and GFRalpha1), and cells expressing these markers were depleted following high-dose busulfan treatment. Furthermore, fresh or cryopreserved germ cells from normal rhesus testes produced colonies of spermatogonia, which persisted as chains on the basement membrane of mouse seminiferous tubules in the primate to nude mouse xenotransplant assay. In contrast, testis cells from animals that received high-dose busulfan produced no colonies. These studies provide basic information about rhesus SSC activity and the impact of busulfan on the stem cell pool. In addition, the germ cell-depleted testis model will enable autologous/homologous transplantation to study stem cell/niche interactions in nonhuman primate testes.
authors.affiliation: Department of Ob/Gyn & Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Hermann
authors.forename: Meena
authors.initials: M
authors.lastname: Sukhwani
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Lin
authors.forename: Yi
authors.initials: Y
authors.lastname: Sheng
authors.forename: Jamie
authors.initials: J
authors.lastname: Tomko
authors.forename: Mario
authors.initials: M
authors.lastname: Rodriguez
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Shuttleworth
authors.forename: David
authors.initials: D
authors.lastname: McFarland
authors.forename: Robin M
authors.initials: RM
authors.lastname: Hobbs
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Pandolfi
authors.forename: Gerald P
authors.initials: GP
authors.lastname: Schatten
authors.forename: Kyle E
authors.initials: KE
authors.lastname: Orwig
mesh_terms: D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000009:adverse effects / Q000494:pharmacology; D002066:Busulfan / Q000009:adverse effects* / Q000494:pharmacology; D015925:Cryopreservation; D004305:Dose-Response Relationship, Drug; D007248:Infertility, Male / Q000139:chemically induced*; D008253:Macaca mulatta; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008954:Models, Biological; D012662:Semen Preservation / Q000009:adverse effects*; D013076:Sperm Count; D013091:Spermatogenesis / Q000187:drug effects; D013093:Spermatogonia / Q000166:cytology* / Q000187:drug effects* / Q000637:transplantation; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology; D013737:Testis / Q000033:anatomy & histology / Q000187:drug effects; D014183:Transplantation, Heterologous
chemical_list: D018906:Antineoplastic Agents, Alkylating; D002066:Busulfan