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01-06-2006 | Original Article

Mitotic activity of Sertoli cells in adult human testis: an immunohistochemical study to characterize Sertoli cells in testicular cords from patients showing testicular dysgenesis syndrome

Authors: Ralph Brehm, Rodolfo Rey, Sabine Kliesch, Klaus Steger, Alexander Marks, Martin Bergmann

Published in: Brain Structure and Function | Issue 3/2006

Abstract

During puberty, normal somatic Sertoli cells undergo dramatic morphological changes due to the differentiation of immature pre-Sertoli cells in functionally active adult Sertoli cells. Sertoli cell maturation is accompanied with loss of their mitotic activity before onset of spermatogenesis and loss of pre-pubertal and occurrence of adult immunohistochemical Sertoli cell differentiation markers. Testes of infertile adult patients often exhibit numerous histological signs of testicular dysgenesis syndrome (TDS) such as microliths, Sertoli cell only (SCO) tubules, tubules containing carcinoma in situ and immature seminiferous tubules (Sertoli cell nodules). Sertoli cell tumours, however, are very rare neoplasms possibly due to the fact that the mechanism and temporal origin of neoplastic Sertoli cells underlying Sertoli cell tumourigenesis still remain unknown. To clarify the state of Sertoli cell differentiation in both immature seminiferous tubules of adult patients with TDS and Sertoli cell tumour, we compared the expression of the Sertoli cell differentiation markers vimentin, inhibin-α, anti-Muellerian-hormone, cytokeratin 18, M2A-antigen, androgen receptor and connexin43 with that of SCO tubules with hyperplasia. In addition, we demonstrated for the first time the existence of proliferating Sertoli cells by Ki67- and PCNA-immunostaining in Sertoli cell nodules of the adult human testis. Our data indicate that mitotically active Sertoli cells in Sertoli cell nodules will be arrested prior to puberty and, contrary to dogma, do not represent foetal or neonatal cells. Since all markers in Sertoli cell nodules revealed a staining pattern identical to that in neoplastic Sertoli cells, but different to that in Sertoli cells of SCO tubules with hyperplasia, it may be speculated that Sertoli cell tumours in adult men may originate from Sertoli cell nodules.

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Title: Mitotic activity of Sertoli cells in adult human testis: an immunohistochemical study to characterize Sertoli cells in testicular cords from patients showing testicular dysgenesis syndrome
Authors: Ralph Brehm
Rodolfo Rey
Sabine Kliesch
Klaus Steger
Alexander Marks
Martin Bergmann
Publication date: 01-06-2006
Publisher: Springer-Verlag
Published in: Brain Structure and Function / Issue 3/2006
Print ISSN: 1863-2653
Electronic ISSN: 1863-2661
DOI: https://doi.org/10.1007/s00429-005-0075-8

At a glance: The STEP trials

Springer Medicine

Mitotic activity of Sertoli cells in adult human testis: an immunohistochemical study to characterize Sertoli cells in testicular cords from patients showing testicular dysgenesis syndrome

Abstract

At a glance: The STEP trials

Springer Medicine

Abstract

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