Long-term culture and significant expansion of human Sertoli cells whilst maintaining stable global phenotype and AKT and SMAD1/5 activation

Abstract

BackgroundSertoli cells play key roles in regulating spermatogenesis and testis development by providing structural and nutritional supports. Recent studies demonstrate that Sertoli cells can be converted into functional neural stem cells. Adult Sertoli cells have previously been considered the terminally differentiated cells with a fixed and unmodifiable population after puberty. However, this concept has been challenged. Since the number of adult human Sertoli cells is limited, it is essential to culture these cells for a long period and expand them to obtain sufficient cells for their basic research and clinic applications. Nevertheless, the studies on human Sertoli cells are restricted, because it is difficult to get access to human testis tissues.ResultsHere we isolated adult human Sertoli cells with a high purity and viability from obstructive azoospermia patients with normal spermatogenesis. Adult human Sertoli cells were cultured with DMEM/F12 and fetal bovine serum for 2 months, and they could be expanded with a 59,049-fold increase of cell numbers. Morphology, phenotypic characteristics, and the signaling pathways of adult human Sertoli cells from different passages were compared. Significantly, adult human Sertoli cells assumed similar morphological features, stable global gene expression profiles and numerous proteins, and activation of AKT and SMAD1/5 during long-period culture.ConclusionsThis study demonstrates that adult human Sertoli cells can be cultured for a long period and expanded with remarkable increase of cell numbers whilst maintaining their primary morphology, phenotype and signaling pathways. This study could provide adequate human Sertoli cells for reproductive and regenerative medicine.Electronic supplementary materialThe online version of this article (doi:10.1186/s12964-015-0101-2) contains supplementary material, which is available to authorized users.

Biology of the Sertoli Cell in the Fetal, Pubertal, and Adult Mammalian Testis

“…Thus, Sertoli cell cultures are a good system for present and future studies. Recent studies show that adult human Sertoli cells can be cultured and expanded in vitro while maintaining their primary characteristics (Chui et al 2011;Guo et al 2015), indicating that they may have use in reproductive medicine. Future studies should continue to investigate the proliferative ability of human Sertoli cells in vivo.…”

BMP6 Regulates Proliferation and Apoptosis of Human Sertoli Cells Via Smad2/3 and Cyclin D1 Pathway and DACH1 and TFAP2A Activation

“…Adult Sertoli cells have previously been considered the terminally differentiated cells that are unable to divide or proliferate. Nevertheless, this concept has recently been challenged28, because Sertoli cells from adult hamster29 and human30 can regain proliferative ability in vitro . We found that exogenous BMP6 promoted the proliferation of human Sertoli cells.…”

Molecular Mechanisms of Cell Differentiation in Gonad Development

“…Fuss (1911Fuss ( , 1912 and Felix (1911) were apparently the first to describe the extragonadal location of PGCs in human embryos. In particular, they reported simultaneous expression of both pluripotency (OCT4, NANOG, PRDM14, and LIN28) and germline-specific (BLIMP1, AP2γ, DAZL, Kit, and DDX4) genes (Guo et al 2015). The putative PGCs were distinguished by their large size, spherical shape, a prominent nucleolus, and the presence of abundant glycogen granules in the cytoplasm.…”

“…The putative PGCs were distinguished by their large size, spherical shape, a prominent nucleolus, and the presence of abundant glycogen granules in the cytoplasm. Moreover, human PGCs express KLF4 (Krupper-like factor 4), a gene encoding a trascription factor involved in pluripotency maintenance, whereas mouse PGC do not express it (Guo et al 2015). Only recently, the first gene and protein expression data on human PGCs at different stages of development were produced.…”

“…Most important, when epigenetic of the PGC-like cells was analyzed, it was found that these cells were characterized by erasure of global DNA methylation, ongoing removal of parental imprinting, and histone modifications similar to endogenous PGCs (Guo et al 2015;Irie et al 2015b;Sugawa et al 2015).…”