Tubulobulbar complexes in Sertoli cell primary cultures

Abstract

In the seminiferous epithelium, unique double membrane structures termed tubulobulbar complexes (TBCs) develop in association with basal junction complexes between Sertoli cells. These actin‐related structures are thought to internalize intercellular junctions during the movement of spermatocytes from basal to adluminal compartments of the epithelium. We are establishing a primary Sertoli cell culture system to study the role of basal TBCs in junction turnover. We confirm that Sertoli cells isolated from 20 day‐old rat pups morphologically differentiate when grown on Matrigel in Transwells. The cells are high cuboidal to columnar in shape with basal nuclei, and with basal junction complexes similar to the appearance of junction complexes between Sertoli cells in vivo. Significantly, TBCs and TBC‐like structures develop in association with intercellular junctions. Double‐membrane coated‐pits, together with double‐membrane tubular structures capped by coated‐pits are observed in regions related to ectoplasmic specializations. When immunostained for integral junction proteins, “rod‐like” structures are observed to extend into the cell from the periphery. These observations indicate that TBCs are able to develop in differentiated Sertoli cells in culture, making further functional analyses of TBCs possible in vitro. Supported by an NSERC Discovery Grant to AWV.Grant Funding Source: NSERC