[doi: 10.5505/2017ichc.PP-93]

Exploration of protein expression by immunohistochemistry of Toll-like receptor 2 (TLR 2) in rat testis and epididymis during postnatal development

Mehmet Özbek1, Emel Ergün2, Feyzullah Beyaz3, Levent Ergün2, Nuh Yıldırım2, Özge Özgenç2, Füsun Erhan2
1Mehmet Akif Ersoy University, Faculty of Veterinary Medicine, Department of Histology and Embryology, Burdur, Turkey
2Ankara University, Faculty of Veterinary Medicine, Department of Histology and Embryology, Ankara, Turkey
3Erciyes University, Faculty of Veterinary Medicine, Department of Histology and Embryology, Kayseri, Turkey

Introduction & Objectives
The testis is an immunoprivileged site, where the local cell-initiated testicular innate immune responses play a crucial role in defense against microbial infections. Toll-like receptors, which are members of pattern recognition receptors, are of great importance in ensuring the continuity of this protected environment of the testis.
This study was conducted to examine the localization and expression of TLR2 in the postnatal period in the rat testes and epididymis.
Materials & Methods
Wistar albino rat testis and epididymis tissues were used as material. Each of the four groups composed of six rats were designed as prepubertal (5 days), pubertal (20 days), postpubertal (50 days) and mature (70 days). The streptavidin–biotin complex (Strept-ABC) immunoperoxidase technique was employed to detect immunohistochemical localization of TLR2 in testes and epididymis.
Results
At 5 old day rats, expression of TLR2 was observed in peritubular myoid cells and TLR2 expression started to appear in some primary spermatocytes at 20 day old rats testis. At 50 day old rats, TLR2 expression was defined some spermatogenic cells in the tubules at various stages and at 70 day old day rats, Immun reaction was determined in both some spermatogenic cells and Sertoli cells. Some interstitial cells with weak immunoreactions were observed in all periods, while intense reaction of blood cells was observed. In epididiymis, TLR2 expression was observed some cells in connective tissue and some epithelial cells of epididymis.
Conclusions
The appearance of TLR2 in Sertoli cells after puberty suggests that TLR2 may contribute to the development of spermatogenic cells as well as being involved in innate immunity.