Are Sertoli cells a kind of mesenchymal stem cells?

OBJECTIVE: Sertoli cells (SCs) are a major component of testis which secrete a variety of cytokines and immunosuppressive factors, providing nutritional support and immune protection for sperm growth and development. The purpose of this study was to investigate the relationship between SCs and bone marrow mesenchymal stem cells (BMSCs) in order to provide a theoretical basis for better application of SCs.

METHODS: We used the adherence method to isolate Sprague-Dawley rat SCs and BMSCs. Cells surface markers were detected by flow cytometry. The capacity of cells to differentiate was determined by osteogenic and adipogenic induction. Assessment of cell proliferation was performed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2-H-tetrazolium bromide] assay. Changes in the nucleus were analyzed by Hoechst nuclear staining. Cell aging was observed with β-galactosidase, which is a biological marker of senescence. RT-PCR was employed to detect the expression of cytokines.

RESULTS: From the aforementioned experiments, we found that the surface markers of SCs and BMSCs were almost exactly the same. Proliferation of SCs, as well as osteogenic and adipogenic differentiation, were weaker than in BMSCs. Compared with BMSCs, Hoechst nuclear staining showed that the chromatin of SCs began to aggregate and was slightly larger. β-galactosidase staining showed that SCs were in a slightly aging state. The secretion of cytokines from SCs was slightly less than the secretion from BMSCs.

CONCLUSION: SCs are a kind of mesenchymal stem cells which have begun the process of differentiation.