Beren KARAOSMANOĞLU, Ekim Zihni TAŞKIRAN

Hastalık modeli olarak dermal fibroblasttan dönüştürülmüş nöron

Amaç: Kişiselleştirilmiş tıp çalışmaları için hastalık modeli oluşturmak önem kazanmıştır. Hastalardan bazı hücre türlerinin alınamıyor olması, hastalık modeli için somatik hücre farklılaştırılmasını gerektirmiştir. Hücrelerin yeniden programlanması için pek çok yöntem bulunmaktadır. İndüklenmiş Pluripotent Kök Hücre (iPKH) ve doğrudan dönüştürme en temel iki yöntemdir. Ancak, iPKH’nin pahalılık, yüksek mutasyon oranı ve farklılaşma hasarları gibi dezavantajlarından dolayı, pek çok araştırmacı doğrudan dönüştürmeyi seçmektedir. Bu çalışmada, dermal fibroblastların doğrudan dönüştürme ile nöronlara farklılaştırılarak kişiye özel hastalık modeli uygulamalarında kullanılabileceği amaçlanmıştır. Yöntem: Ticari olarak satın alınmış dermal fibroblastlar lamel üzerine ekilerek küçük kimyasallar içeren besiyeri ile 24 saat süresince indüklenmiştir. Hücreler taramalı elektron mikroskobu ile görüntülenmiş ve yeni nesil RNA dizileme ile transkriptom analizi gerçekleştirilmiştir. Bulgular: 24 saatlik indükleme sonucunda nöral hücre morfolojisi görülmüştür. Transkriptom sonuçlarında nöral genlerin artmış olduğu tespit edilmiştir. Sonuç: Dermal fibroblastlar küçük moleküller kullanılarak doğrudan dönüştürme ile başarılı olarak indüklenmiştir.

Neuronal conversion of dermal fibroblasts as a disease model

Objective: Disease modelling applications are gaining importance especially for the need of patient-specific studies.Because some cell types cannot be obtained from patients, somatic cell differentiation is needed for disease modelling.There are many methods for somatic cell reprogramming. Induced Pluripotent Stem Cells (iPSCs) and direct conversionare the main techniques. However, due to the disadvantages of iPSCs, such as expense, high mutation rate anddifferentiation defects, many researches choose direct conversion for reprogramming.In this study, we aimed to reprogram dermal fibroblasts into neurons with direct conversion in order them to bepotentially used for patient-specific disease modelling applications.Method: Commercially purchased dermal fibroblasts were seeded on coverslips and then induced with a mediumcontaining small chemicals for 24 hours. Cells were visualized by scanning electron microscopy and transcriptomeanalysis was done by next generation RNA sequencing.Results: Neuronal cell morphology was observed after 24 hour induction. According to the transcriptomic data,neuronal genes were upregulated.Conclusions: Dermal fibroblasts were successfully induced into neurons by direct conversion with using smallchemicals.

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