模拟Leydig细胞微环境诱导骨髓基质干细胞向雄激素分泌细胞分化

Bilateral anorchia and testosterone deficiency caused by hypogonadism, aging, or traumatic testes loss can may cause loss of testicular function, ambiguous genitalia, puberty failure, infertility, and psychological disorders. Common treatments include androgen supplementation or replacement, and testicular prosthetic implantation, while both therapies are associated with complications. Tissue engineering technique provides a potential approach for solving the above problem. As Leydig cells (LCs) were known as the primary source of testosterone in mammalians, our in vivo study had previously proved the feasibility of reconstructing testis testosterone-secreting function by tissue engineering approach which combined LCs with polyglycolic acid (PGA) scaffolds to regenerate testis-like tissue with sustained testosterone-secreting function in a rat model. Nevertheless, the successful regeneration of tissue engineered testis-like tissue (TET) relies on large numbers of functional LCs, the scarcity of allogenic Leydig cells has prevented leydig cell implantation from being a realistic practice. Several studies have demonstrated that bone marrow stem cells (BMSCs), in a favorable testicular environment, can differentiate into Leydig cell lineage. However, the low yield and testosterone secreting function of BMSCs derived LCs remains a problem. Our previous study proved that the stem Leydig cells (SLCs) existing in the Leydig cell lineage, which was isolated from preperbtal animals by a patented technique of our study group, could proliferate and differentiate activly in vitro, with the process greatly mimicing the in vivo proliferation and differentiation of preperbtal LCs. In this study, we aim to in vitro dupicate the LCs differenciation process, and test the feasibility of inducing BMSCs into functional Leydig cell lineage by co-culturing BMSCs with Leydig cells of preperbtal rats, and then will fully evaluate its clinical relevence. This study would help to establish a noval approach on cell differenciation research, paving a way for realizing functional differenciation of multi-functional stem cells by combination of cell co-culture and and conditional induction.

睾丸缺失/雄激素缺乏症对患者身心有较大影响，合理补充雄激素与形态重建是解决该疾病的根本途径，但传统疗法存在弊端。以Leydig细胞（LC,雄激素来源）为基础构建生物相容性雄激素分泌组织，可将生理性激素补充与组织充填有效结合；然而LC来源一直存在瓶颈。诱导骨髓基质干细胞（BMSC）分化是获得LC的重要途径，虽然目前诱导分化效率偏低、功能欠佳，但研究表明，在体内LC增殖分化期微环境中BMSC可高效率地分化为功能型LC。申请人研究发现，自幼龄动物可获取LC系分化期各级细胞成分，并在特定条件下实现了LC大量体外增殖、分化。以此为基础，本项目将以细胞亚群筛选、细胞因子干预、激素调节等手段，探讨体外诱导BMSC向LC分化的影响因素，实现对LC增殖/分化的微环境的体外模拟、并诱导BMSC向雄激素分泌细胞高效分化，以解决LC来源不足与功能不全的难题。进而建立共培养与条件诱导有机结合的干细胞诱导分化新模式。