EXPRESSION OF VIMENTIN, CYTOKERATIN, AND DESMIN IN SERTOLI CELLS OF HUMAN FETAL, CRYPTORCHID, AND TUMOR-ADJACENT TESTICULAR TISSUE

The intermediate filament of mature human Sertoli cells is vimentin. A co-expression of vimentin together with cytokeratin has been demonstr ated in Sertoli cells during embryonal development and under pathologi c conditions in adult testes. We analysed the presence of vimentin, cy tokeratin, and desmin in Sertoli cells of fetal testes (n=20), in semi niferous tubules of cryptorchid testes (n=10) and adjacent to testicul ar germ cell tumours (n=47) using specific monoclonal antibodies and s ingle and double-labelling immunohistochemistry. During embryonal deve lopment prominent cytokeratin expression disappears after the 20th wee k of gestation. Interestingly, we also found desmin in immature intrat ubular Sertoli cells between weeks 11 and 14. In adult cryptorchid tes tes and in peritumour tubules, desmin was also prominently present in Sertoli cells in the vast majority of the cases investigated, as well as vimentin and cytokeratin co-expression. This first description of d esmin immunoreactivity may shed some light on the ontogeny of human Se rtoli cells and demonstrates that this cell type is able to express th ree types of inter-mediate filaments in a complex manner.