Sertoli ceils are the cells that line the seminiferous tubules in the testes. These cells protect the spermatids and convey nutrients to both the developing and mature spermatozoa. Sertoli cells are regulated by FSH (follicle stimulating hormone) as the FSH receptors are confined to the Sertoli cells. FSH stimulates sertoli cells to produce androgen-binding protein and inhibin; and together with testosterone, promotes the proliferation of Sertoli cells.