Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Mühendislik Bilimleri Bölümü, Türkiye
Tezin Onay Tarihi: 2018
Öğrenci: MILAD FATHI ACHACHELOUEI
Danışman: AYŞEN TEZCANER
Özet:The aim of this study was to develop bFGF and TGF-β1 loaded polymeric nanoparticles (PNPs) and dental pulp stem cells (DPSCs) containing dimethacrylated poly(ethylene glycol) (PEGDMA)/silk fibroin hydrogels as scaffolds for regeneration of the cartilage tissue. Poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) were prepared with double emulsion-solvent evaporation technique. The effect of different excipients (poly(2-ethyl-2-oxazoline) (PetOx), heparin and Kolliphor P 188) on the entrapment efficiency of growth factors in NPs and release kinetics from PLGA NPs in PBS at 37°C was investigated. For preparation of bFGF and TGF-β1 loaded NPs 0.5% and 1.0% (W/V) heparin excipients have been chosen, respectively. bFGF loaded NPs with 0.5% (W/V) heparin has shown highest cumulative percent release, encapsulation efficiency and loading capacity of 51.39 ± 2.22%, 88.1 ± 0.3% and 8.97 ± 0.34%, respectively and highest cell viability in monolayer study. TGF-β1 loaded PLGA NPs with 1.0% (W/V) as excipient was chosen due to highest cumulative percent release, encapsulation efficiency and loading capacity of 13.28 ± 0.19%, 99.65 ± 0.1%, 9.90 ± 0.10%, respectively and cell viability in monolayer study among all excipient groups. Hydrogels composed of silk fibroin and PEGDMA (PEGDMA (10, 15 and 20%) at different volume ratios (silk fibroin: PEGDMA, 3:1, 1:1, 1:3)) were prepared by crosslinking fibroin with sonication and PEGDMA with vi UV photocrosslinking. Hydrogels with various compressive moduli ranging from 95.70 ± 17.82 kPa to 338.05 ± 38.24 kPa were obtained through changing both concentration of PEGDMA and volume ratio of PEGDMA with 8% silk fibroin. 10% (W/W) NPs addition to hydrogels significantly increased their compressive moduli (p ≤ 0.05). Weight loss of blend hydrogels with highest silk fibroin content was the highest among all groups (89.93 ± 7.95% in 28 days). Highest cell viability was observed in PEG10-SF8(1:1) hydrogel group and this hydrogel composition was chosen for preparing hydrogels containing DPSCs and PLGA NPs. Live/dead assay has shown almost no dead cells and also elongated cells inside hydrogels containing both bFGF and TGF-β1 loaded NPs on 7th day. DNA and GAG amounts of hydrogels containing bFGF and TGF-β1 loaded NPs were significantly higher than hydrogels without NPs, empty NPs, and TGF-β1 loaded or bFGF loaded NPs (p ≤ 0.05), showing synergistically effect of dual release of bFGF and TGF-β over proliferation and chondrogenic differentiation of DPSCs in hydrogels. Overall, we conclude that PEG10-SF8(1:1) hydrogel system containing DPSCs and bFGF and TGF-β1 loaded PLGA NPs hold promise for cartilage tissue engineering.