MEHMET ÖZBEK, EMEL ERGÜN, LEVENT ERGÜN, FEYZULLAH BEYAZ, Füsun ERHAN, Banu KANDİL, Nuh YILDIRIM, ÖZGE ÖZGENÇ

Toll-Like Receptor 2 Expression on Ovine Ileum throughout Fetal Development

Toll-like receptors (TLRs) family activated by endogenous host molecules or microbial components are pattern recognition receptors. Among all TLRs, TLR2 regulates intestinal inflammation, neuromuscular function, enteric nervous system structure, and neurochemical coding. In the present study, we aimed to investigate TLR2 expression on ovine ileum throughout prenatal development by using immunohistochemistry. We examined the fetal period in three different stages (fetal 60-100 days, fetal 100-125 days, and fetal 125-150 days). Moderate labeling was observed in most intestinal epithelial cells and follicle associated epithelium of Peyer’s patches while some intestinal epithelial cells showed intense immunostaining. We also detected TLR2 expression in the majority of follicular immune cells, ganglion cells of submucosal and myenteric plexus, smooth muscles of the tunica and lamina muscularis, and blood vessels. In conclusion, this is the first study to describe expression profile of TLR2 in ovine ileum during prenatal development. TLR2 expression in the ileal ontogenesis has been shown to begin in the prenatal period. Almost all the intestinal epithelial cells and enteric neurons showed TLR2 expression. The presence of TLR2 expression in smooth muscles suggests that smooth muscles may be associated with immune system other than contracting task.

Fötal gelişim Boyunca Koyun İleumundaki Toll like Reseptör 2 Ekspresyonu

Endojen veya mikrobiyal komponentlerle aktive olan Toll-like reseptörler (TLR) patern tanıyan reseptörlerdir. Bu reseptörler arasında yer alan TLR2 intestinal inflamasyonu, nöromüsküler fonksiyonu, enterik sinir sistemi yapısını ve nörokimyasal kodlamayı düzenler. Bu çalışmada, prenatal dönemde koyun ileumunda TLR2 ekspresyonunun immunohistokimyasal yöntemle araştırılması amaçlandı. Prenatal dönem 3 ayrı bölümde incelendi (60-100, 100-125, 125-150). İntestinal ve folikülle ilişkili epitelde orta derecede boyanma gözlenirken, bazı intestinal epitel hücrelerinde yoğun intrasitoplazmik immun reaksiyon tespit edildi. Ayrıca, foliküllerdeki hücrelerin büyük çoğunluğunda, submukozal ve myenterik pleksuslardaki gangliyon hücrelerinde, tunika muskularis, lamina muskularis ve damar duvarlarındaki düz kaslarda da TLR2 ekspresyonuna rastlandı. Sonuç olarak, bu çalışma prenatal gelişim süresince koyun ileumunda TLR2 ekspresyon profilini tanımlayan ilk araştırmadır ve ileumdaki TLR2 ontogenezisin doğum öncesi dönemde başladığı gösterilmiştir. Hemen hemen tüm intestinal epitel hücreleri ve enterik nöronlar TLR2 ekspresyonu gösterdi. Düz kaslarda TLR2 ekspresyonunun varlığı, düz kasların kasılma görevi dışında bağışıklık sistemi ile ilişkili olabileceğini göstermektedir.

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