The Co-culture of Sertoli Cells and Germ Cells: Applications in Toxicology

Spermatogenesis is a very complex process by which male germ cells differentiate into mature spermatozoa. In this regard, the local regulation of spermatogenesis can be considered as a particular cellular achievement. This sophisticated communication network has its weak points, such that the dysfunctionment of one cell type propagates to all other cell types as a cascade. This explains the particular vulnerability of the testis to environmental factors, and more specifically drugs and xenobiotics, and the general difficulty encountered by the toxicologist in identifying the testicular cell target of a given toxicant and hence its precise mode of action. More or less complex culture systems of isolated testicular cells have been developed over the past decades which represent very useful tools for the toxicologist. Among the different testicular cell types, Sertoli and Leydig cells, have been the ones most usually used for the in vitro analysis of toxic compounds. While Sertoli cells are used in vitro for mechanistic toxicology studies, the extreme fragility of germ cells prevents their culture for that purpose. However, Sertoli and germ cells can be cultured together for short periods of time. This review presents the different in vitro testicular systems at disposal and provides examples of mechanistic studies undertaken to verify and deepen in vivo observations on the targets to reproductive toxicants.