Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada.
Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada.
Int J Mol Sci. 2021 Dec 17;22(24):13549. doi: 10.3390/ijms222413549.
Male survivors of childhood cancer are at risk of suffering from infertility in adulthood because of gonadotoxic chemotherapies. For adult men, sperm collection and preservation are routine procedures prior to treatment; however, this is not an option for pre-pubertal children. From young boys, a small biopsy may be taken before chemotherapy, and spermatogonia may be propagated in vitro for future transplantation to restore fertility. A robust system that allows for scalable expansion of spermatogonia within a controlled environment is therefore required. Stirred suspension culture has been applied to different types of stem cells but has so far not been explored for spermatogonia. Here, we report that pre-pubertal porcine spermatogonia proliferate more in bioreactor suspension culture, compared with static culture. Interestingly, oxygen tension provides an avenue to modulate spermatogonia status, with culture under 10% oxygen retaining a more undifferentiated state and reducing proliferation in comparison with the conventional approach of culturing under ambient oxygen levels. Spermatogonia grown in bioreactors upregulate the Wnt/ β-catenin pathway, which, along with enhanced gas and nutrient exchange observed in bioreactor culture, may synergistically account for higher spermatogonia proliferation. Therefore, stirred suspension bioreactors provide novel platforms to culture spermatogonia in a scalable manner and with minimal handling.
男性癌症患儿幸存者由于性腺毒性化疗而在成年后有不孕的风险。对于成年男性，在治疗前通常会进行精子采集和保存；然而，对于青春期前的儿童来说，这不是一个选择。从小男孩身上，可以在化疗前进行小活检，并且可以在体外增殖精原细胞，以备将来移植以恢复生育能力。因此，需要建立一个允许在受控环境中大规模扩增精原细胞的强大系统。搅拌悬浮培养已应用于不同类型的干细胞，但迄今为止尚未探索用于精原细胞。在这里，我们报告说，与静态培养相比，青春期前猪精原细胞在生物反应器悬浮培养中增殖更多。有趣的是，氧气张力提供了一种调节精原细胞状态的途径，与在常规培养条件下培养相比，在 10%以下的氧气培养下保持更未分化的状态并减少增殖。在生物反应器中生长的精原细胞上调 Wnt/β-连环蛋白通路，这与生物反应器培养中观察到的增强的气体和营养物质交换协同作用，可能导致更高的精原细胞增殖。因此，搅拌悬浮生物反应器提供了新颖的平台，以可扩展的方式和最小的处理量培养精原细胞。
