Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
2 results
Search Results
Master Thesis Development and Characterization of Magnesium Alginate Hydrogels for 3d Cell Culture Formation(01. Izmir Institute of Technology, 2021) Çoban, Başak; Arslan Yıldız, AhuCell culture is an important tool for biological research. Two-dimensional (2D) cell culture is still used but growing cells on plastic surfaces offering unnatural growth kinetics and cell attachment. Three-dimensional (3D) cell culture allows cells to growth in their 3D physical shape and interact with their surroundings which represent the natural microenvironment. Hydrogels are crosslinked networks, have become increasingly used biomaterial for 3D cell culture with their ability to simulate the nature of most soft tissues. In this thesis, a new methodology based on bio-patterning was developed to fabricate (3D) cellular structures by using Mg-alginate hydrogel and fabricated 3D cellular structures was utilized for drug screening studies. Mg-alginate hydrogel has a specific gelation/de-gelation characteristics compared to other types of hydrogels due to its weak polymer-ion interaction. In this study slow gelation and de-gelation property of Mg-alginate hydrogel was used for biopatterning of 3D cellular structures. Plackett-Burman and Box-Behnken design models were used to optimize parameters of Mg alginate-based biopatterning method while using HeLa cells as a model cell line. Then, the applicability of newly developed methodology was successfully demonstrated by using SaOS-2 and SH-SY5Y cells to fabricate 3D cellular structures. Cell proliferation and migration profiles were observed during long-term culturing with time-dependent light microscopy images. Also cell proliferation and viability of long-term cultured tumor models were analyzed by using Alamar Blue and Live/Dead assays. Moreover, F-actin, Collagen I, and DAPI staining/immunostaining was done to investigate cellular and extracellular components of 3D cellular structures for short and long-term culture times. Finally, the dose-response of fabricated 3D structures was evaluated and compared with standard 2D cell culture by applying doxorubicin (DOX). The IC50 values were calculated for 3D cellular structure of HeLa, SaOS-2 and SH-SY5Y cells as 8.2, 7.8, and 2.1 µM respectively while IC50 values of 2D controls obtained as 3.2, 4.4, and 0.2 µM respectively. These results were also statistically analyzed and dose responses were found significantly different according to t-test, which means 3D cellular structures were more resistant to drug exposure compared to 2D cell culture.Master Thesis Lab-on-a-chip devices for drug screening(Izmir Institute of Technology, 2019) Gökçe, Begüm; Pesen Okvur, Devrim; Çağır, AliBreast cancer is one of the cancers with the highest incidence and mortality rates in women in Turkey as well as in the world. Tumor micro environment comprises of cancer and normal cells, extracellular matrix, soluble biological and chemical factors. Research has shown that cell shape, adhesion, migration, response to growth factors and drugs are different in 2D and 3D culture. Today, only 8 out of 100 anti-cancer clinical trial gives effective results. 3D cell culture systems have shown to be a necessary step between in vitro, in vivo and clinical studies. Therefore, it is necessary to better understand the interactions of cancer cells with their micro environment, for which new cell culture setups are required. The most apparent disadvantage of widely used 3D cell culture setups is the lack of stromal cells. The systems to be developed should both provide a 3D environment and comprise multiple cell types. The drug screen in 3D tri-culture method with a lab-on-a-chip device, that will be developed in this study will be able to answer these needs. Cell lines that represent different breast cancer types alone or together with stromal cells were cultured in 3D in the to be developed lab-on-a-chip; by determining the effects of drugs with different targets on the viability and distribution of cells, a drug screening method is developed.