Abstract
Techniques have been developed for isolating and cultivating mammalian [rat] Sertoli cells in vitro. Under appropriate conditions, pure cultures of Sertoli cells continue indefinitely, giving rise eventually to heteroploid cell strains. Diploid as well as heteroploid cells display typical nuclear and cytoplasmic morphology of Sertoli cells, active amoeboid movements, pinocytosis, and phagocytosis. On the basis of observations made during cultivation of Sertoli cells, their possible functions in vivo are considered to be harboring immature spermatids to prevent them from being transported away from the germinal epithelium, nursing undeveloped spermatids for maturation to sperms, and protecting germ cells from microbial infection by phagocytizing invading microorganisms.