Neslihan TAŞÇENE, Zeynep İŞGÜDER, Berrin SALMANOĞLU

Osteopontin expression in polarized MDCK cells

Çalışmada, farklı hücre yoğunluklarındaki (%10, 50, 90 ve 100) Madin-Darby Canine Kidney (MDCK) hücrelerinde, osteopontin (OPN) ekspresyonunun araştırılması amaçlandı. OPN ekspresyonu, western blotting ile araştırıldı. Polarizasyonun başlamasını takiben ve hücre yoğunluktaki artışa bağlı OPN ekspresyonunda artış gözlendi. Hücrelerdeki fotillin-2nin ekspresyon profili kontrol olarak kullanıldı. Flotillin-2 proteininin ekspresyon hızı, hücre yoğunluğu ve/veya polarizasyona bağımlı olmadan MDCK hücrelerince üretilmektedir. OPNnin hücre içi dağılımı anti-OPN antikor ile immun işaretleme yapılarak konfokal mikroskopta görüntülendi. MDCK hücrelerindeki hücre yoğunluğuna bağlı artan OPN ekspresyonu, görüntülenen bantlarla teyit edildi. Özellikle OPNnin mannozdan zengin izoformlarının ekspresyonunun uyarıldığı tespit edildi. Sonuçlara göre, hücre yoğunluğu ve polarizasyona bağlı olarak, MDCK hücrelerinde OPN ekspresyonunda artış gözlendi. Hücre yoğunluğu ve polarizasyon durumu, mannozdan zengin OPNnin ekspresyon profili üzerine önemli etkisi bulunmaktadır.

Polarize MDCK hücrelerinde osteopontin ekspresyonu

The aim of this study is to indicate expression of osteopontin (OPN) in Madin-Darby Canine Kidney (MDCK) cells with diferent confuences (10, 50, 90, 100%). OPN expression were investigated by western blotting. An increase in OPN expression was observed due to the increased confuency and subsequent initiation of polarization. Expression profiles of fotillin-2 in the same cells were used as a control, since this protein is ubiquitously produced in MDCK cells and its expression rates are independent of confuence and / or polarization. Intracellular distribution of OPN was also monitored by confocal microscopy on preparations immunolabeled with anti-OPN antibodies. Staining patterns have also confirmed increased OPN expression, especially mannose rich isoforms showed an increase dependent on confuency and polarization in MDCK cells. The results were concluded that increased OPN expression during confuency and polarization in MDCK cells. The state of confuence and polarization have significant efects on the mannose rich OPN expression profile.

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