Master of Engineering Science
Dr. Kibret Mequanint
The in vitro vascular tissue engineering paradigm seeks to produce biologically responsive vascular substitutes using cells, biodegradable scaffolds, and bioreactors to mature the tissue for the potential treatment of vascular occlusions and to create 3D tissue models for pre-clinical testing. In this work, a poly (ester amide) (PEA) derived from from L-phenylalanine, sebacoyl chloride and 1,4 butanediol was synthesized and electrospun to form both 3D fibrous mats and tubular constructs. Both the polymer solution concentration and mandrel rotation speed were optimized to fabricate bead-free fibres. Cytocompatibility and proliferation studies using mesenchymal progenitor 10T1/2 cells showed PEA fibres were not cytotoxic and were able to support proliferation for 14 days. 10T1/2 cells demonstrated increased attachment and spreading for up to 7 days on fibrous mats but perfusion bioreactor studies on tubular scaffolds did not demonstrate sufficient cell infiltration. 10T1/2 cell differentiation studies using qPCR and Western blot showed a TGFβ1 induced upregulation in both the gene and protein expression of vascular smooth muscle cell (VSMC) specific markers smooth muscle alpha-actin (SM- a-actin) and smooth muscle myosin heavy chain (SM-MHC) on PEA fibres, with the differentiation further confirmed using immunofluorescence staining. Overall, this in vitro model of 10T1/2 cell differentiation may serve as a potential platform to fabricate small-diameter tissue engineered vascular grafts.
Kiros, Sarah, "Electrospinning of poly (ester amide) fibres for mesenchymal progenitor cell differentiation" (2016). Electronic Thesis and Dissertation Repository. 4205.