AUTHOR=Matilionyte Gabriele , Tharmalingam Melissa D. , Sanou Iris , Lopes Federica , Lane Sheila , Stukenborg Jan-Bernd , Spears Norah , Anderson Richard A. , Mitchell Rod T. 

TITLE=Maintenance of Sertoli Cell Number and Function in Immature Human Testicular Tissues Exposed to Platinum-Based Chemotherapy—Implications for Fertility Restoration

JOURNAL=Frontiers in Toxicology

VOLUME=4

YEAR=2022

URL=https://www.frontiersin.org/journals/toxicology/articles/10.3389/ftox.2022.825734

DOI=10.3389/ftox.2022.825734

ISSN=2673-3080

ABSTRACT=<p><bold>Background:</bold> Retrospective studies in adult survivors of childhood cancer show long-term impacts of exposure to alkylating chemotherapy on future fertility. We recently demonstrated germ cell loss in immature human testicular tissues following exposure to platinum-based chemotherapeutic drugs. This study investigated the effects of platinum-based chemotherapy exposure on the somatic Sertoli cell population in human fetal and pre-pubertal testicular tissues.</p><p><bold>Methods:</bold> Human fetal (<italic>n</italic> = 23; 14–22 gestational weeks) testicular tissue pieces were exposed to cisplatin (0.5 or 1.0 μg/ml) or vehicle for 24 h <italic>in vitro</italic> and analysed 24–240 h post-exposure or 12 weeks after xenografting. Human pre-pubertal (<italic>n</italic> = 10; 1–12 years) testicular tissue pieces were exposed to cisplatin (0.5 μg/ml), carboplatin (5 μg/ml) or vehicle for 24 h <italic>in vitro</italic> and analysed 24–240 h post-exposure; exposure to carboplatin at 10-times the concentration of cisplatin reflects the relative clinical doses given to patients. Immunohistochemistry was performed for SOX9 and anti-Müllerian hormone (AMH) expression and quantification was carried out to assess effects on Sertoli cell number and function respectively. AMH and inhibin B was measured in culture medium collected post-exposure to assess effects on Sertoli cell function.</p><p><bold>Results:</bold> Sertoli cell (SOX9<sup>+ve</sup>) number was maintained in cisplatin-exposed human fetal testicular tissues (7,647 ± 459 vs. 7,767 ± 498 cells/mm<sup>2</sup>; <italic>p</italic> &gt; 0.05) at 240 h post-exposure. No effect on inhibin B (indicator of Sertoli cell function) production was observed at 96 h after cisplatin (0.5 and 1.0 μg/ml) exposure compared to control (21 ± 5 (0.5 μg/ml cisplatin) vs. 23 ± 7 (1.0 μg/ml cisplatin) vs. 25 ± 7 (control) ng/ml, <italic>p</italic> &gt; 0.05). Xenografting of cisplatin-exposed (0.5 μg/ml) human fetal testicular tissues had no long-term effect on Sertoli cell number or function (percentage seminiferous area stained for SOX9 and AMH, respectively), compared with non-exposed tissues. Sertoli cell number was maintained in human pre-pubertal testicular tissues following exposure to either 0.5 μg/ml cisplatin (6,723 ± 1,647 cells/mm<sup>2</sup>) or 5 μg/ml carboplatin (7,502 ± 627 cells/mm<sup>2</sup>) compared to control (6,592 ± 1,545 cells/mm<sup>2</sup>).</p><p><bold>Conclusions:</bold> This study demonstrates maintenance of Sertoli cell number and function in immature human testicular tissues exposed to platinum-based chemotherapeutic agents. The maintenance of a functional Sertoli cell environment following chemotherapy exposure suggests that fertility restoration by spermatogonial stem cell (SSC) transplant may be possible in boys facing platinum-based cancer treatment.</p>