{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:47:47Z","timestamp":1787028467543,"version":"build-2736575974"},"reference-count":68,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,24]],"date-time":"2021-12-24T00:00:00Z","timestamp":1640304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100006280","name":"American Urological Association","doi-asserted-by":"publisher","award":["Urology Care Foundation Research Scholar Award"],"award-info":[{"award-number":["Urology Care Foundation Research Scholar Award"]}],"id":[{"id":"10.13039\/100006280","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Klinefelter syndrome (KS) is characterized by a masculine phenotype, supernumerary sex chromosomes (usually XXY), and spermatogonial stem cell (SSC) loss in their early life. Affecting 1 out of every 650 males born, KS is the most common genetic cause of male infertility, and new fertility preservation strategies are critically important for these patients. In this study, testes from 41, XXY prepubertal (3-day-old) mice were frozen-thawed. Isolated testicular cells were cultured and characterized by qPCR, digital PCR, and flow cytometry analyses. We demonstrated that SSCs survived and were able to be propagated with testicular somatic cells in culture for up to 120 days. DNA fluorescent in situ hybridization (FISH) showed the presence of XXY spermatogonia at the beginning of the culture and a variety of propagated XY, XX, and XXY spermatogonia at the end of the culture. These data provide the first evidence that an extra sex chromosome was lost during innate SSC culture, a crucial finding in treating KS patients for preserving and propagating SSCs for future sperm production, either in vitro or in vivo. This in vitro propagation system can be translated to clinical fertility preservation for KS patients.<\/jats:p>","DOI":"10.3390\/ijms23010173","type":"journal-article","created":{"date-parts":[[2021,12,24]],"date-time":"2021-12-24T08:38:46Z","timestamp":1640335126000},"page":"173","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["In Vitro Propagation of XXY Undifferentiated Mouse Spermatogonia: Model for Fertility Preservation in Klinefelter Syndrome Patients"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4409-7652","authenticated-orcid":false,"given":"Guillermo","family":"Galdon","sequence":"first","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"},{"name":"Facultad de Medicina Universidad de Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicholas A.","family":"Deebel","sequence":"additional","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"},{"name":"Department of Urology, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nima Pourhabibi","family":"Zarandi","sequence":"additional","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark J.","family":"Pettenati","sequence":"additional","affiliation":[{"name":"Section of Medical Genetics, Department of Pathology, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stanley","family":"Kogan","sequence":"additional","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"},{"name":"Department of Urology, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Wang","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, The Lundquist Institute and Harbor-UCLA Medical Center, Torrance, CA 90502, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ronald S.","family":"Swerdloff","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, The Lundquist Institute and Harbor-UCLA Medical Center, Torrance, CA 90502, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8186-2160","authenticated-orcid":false,"given":"Anthony","family":"Atala","sequence":"additional","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"},{"name":"Department of Urology, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanhe","family":"Lue","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, The Lundquist Institute and Harbor-UCLA Medical Center, Torrance, CA 90502, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4377-4404","authenticated-orcid":false,"given":"Hooman","family":"Sadri-Ardekani","sequence":"additional","affiliation":[{"name":"Wake Forest Institute for Regenerative Medicine (WFIRM), Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"},{"name":"Department of Urology, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1016\/S0140-6736(04)16678-6","article-title":"Klinefelter\u2019s Syndrome","volume":"364","author":"Lanfranco","year":"2004","journal-title":"Lancet"},{"key":"ref_2","first-page":"209","article-title":"Sex Chromosome Abnormalities Found among 34,910 Newborn Children: Results from a 13-Year Incidence Study in Arhus, Denmark","volume":"26","author":"Nielsen","year":"1990","journal-title":"Birth Defects Orig. 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