{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T15:08:05Z","timestamp":1792249685452,"version":"4.4.0"},"reference-count":91,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,26]],"date-time":"2023-01-26T00:00:00Z","timestamp":1674691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Human prepubertal testicular tissues are rare, but organ culture conditions to develop a system for human in vitro-spermatogenesis are an essential option for fertility preservation in prepubertal boys subjected to gonadotoxic therapy. To avoid animal testing in line with the 3Rs principle, organ culture conditions initially tested on human adult testis tissue were applied to prepubertal samples (n = 3; patient ages 7, 9, and 12 years). Tissues were investigated by immunostaining and transmission electron microscopy (TEM), and the collected culture medium was profiled for steroid hormones by liquid chromatography-tandem mass spectrometry (LC-MS\/MS). Culture conditions proved suitable for prepubertal organ culture since SSCs and germ cell proliferation could be maintained until the end of the 3-week-culture. Leydig cells (LCs) were shown to be competent for steroid hormone production. Three additional testis tissues from boys of the same age were examined for the number of germ cells and undifferentiated spermatogonia (SPG). Using TEM micrographs, eight tissues from patients aged 1.5 to 13 years were examined, with respect to the sizes of mitochondria (MT) in undifferentiated SPG and compared with those from two adult testicular tissues. Mitochondrial sizes were shown to be comparable between adults and prepubertal boys from approximately 7 years of age, which suggests the transition of SSCs from normoxic to hypoxic metabolism at about or before this time period.<\/jats:p>","DOI":"10.3390\/cells12030415","type":"journal-article","created":{"date-parts":[[2023,1,27]],"date-time":"2023-01-27T02:30:38Z","timestamp":1674786638000},"page":"415","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Germ Cell Maintenance and Sustained Testosterone and Precursor Hormone Production in Human Prepubertal Testis Organ Culture with Tissues from Boys 7 Years+ under Conditions from Adult Testicular Tissue"],"prefix":"10.3390","volume":"12","author":[{"given":"Neels Lennart","family":"Aden","sequence":"first","affiliation":[{"name":"Clinic and Polyclinic for Dermatology and Venerology, Andrological Section, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Bleeke","sequence":"additional","affiliation":[{"name":"Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uwe R.","family":"Kordes","sequence":"additional","affiliation":[{"name":"Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bianka","family":"Brunne","sequence":"additional","affiliation":[{"name":"Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Holstermann","sequence":"additional","affiliation":[{"name":"Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0820-8231","authenticated-orcid":false,"given":"Ronald","family":"Biemann","sequence":"additional","affiliation":[{"name":"Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University of Leipzig, 04103 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uta","family":"Ceglarek","sequence":"additional","affiliation":[{"name":"Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University of Leipzig, 04103 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Armin","family":"Soave","sequence":"additional","affiliation":[{"name":"Department of Urology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Salzbrunn","sequence":"additional","affiliation":[{"name":"Clinic and Polyclinic for Dermatology and Venerology, Andrological Section, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan W.","family":"Schneider","sequence":"additional","affiliation":[{"name":"Clinic and Polyclinic for Dermatology and Venerology, Andrological Section, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4362-7973","authenticated-orcid":false,"given":"Kathrein","family":"von Kopylow","sequence":"additional","affiliation":[{"name":"Clinic and Polyclinic for Dermatology and Venerology, Andrological Section, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1097\/MED.0000000000000156","article-title":"Testicular function and fertility preservation after treatment for haematological cancer","volume":"22","author":"Jahnukainen","year":"2015","journal-title":"Curr. 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