Modulation of Sertoli cell functions in the two-chamber assembly by peritubular cells and extracellular matrix.

A two-chamber assembly has been employed to investigate influences of peritubular cells (PC) and extracellular matrix (Matrigel) on barrier formation by Sertoli cells (SC) in culture and on transferrin production. The kinetics of transport of [3H]inulin across a Millipore filter were essentially the same in the presence or absence of Matrigel or PC. In contrast, a SC monolayer retarded the diffusion of [3H]inulin, increasing the estimated time for 50% equilibration from about 4 h to approximately 12 h. Matrigel and PC each independently further increased the equilibration time, with the largest effects elicited by the presence of Matrigel (approximately 21 h). Data have been interpreted to indicate that these two components, especially extracellular matrix, facilitate the formation of a functional barrier by SC in the two-chamber system. PC assume a more important role than Matrigel in the modulation of transferrin secretion by SC. Transferrin concentrations were higher in the inner chamber, corresponding to those in the adluminal compartment, but transferrin masses were higher in the outer chamber under the conditions described. We report the effects of the presence and absence of Matrigel, PC, and FSH on levels of transferrin secreted by SC. Addition of FSH resulted in increased transferrin secretion by SC maintained under all conditions examined. We compare our data with those previously reported by others and attempt to provide a basis for the differences observed. We discuss the properties of the system and outline major advantages and limits of the two-chamber assembly in investigations on the polarity and properties of SC in culture.