Sertoli cell A supporting cell projecting inward from the basement membrane of seminiferous tubules. They surround and nourish the developing male germ cells and secrete androgen binding protein. Their tight junctions with the spermatogonia and spermatocytes provide a blood-testis barrier. FMA:72298 ZFA:0009133 CALOHA:TS-0922 VHOG:0001348 BTO:0001238 androgen binding protein secreting cell supporting cell seminiferous tubule epithelial cell secretory epithelial cell