Speaker
Description
Natural scaffolds derived from living tissue have been used in clinical applications. They provide similar architecture and composition to the target tissue and can be remodelled as desired. However, they still have some drawbacks as there is a risk of disease transmission and may require additional surgery. Therefore, extracellular matrix (ECM) based biohybrid scaffolds have been developed using synthetic scaffolds as templates. Mechanical stimulation is proved to be helpful in cell proliferation and collagen production. However, there is limited information regarding the most appropriate technique and mechanical regime for generating biohybrid scaffolds. This project focuses on optimising the PGSM scaffolds and mechanical regime to induce cell proliferation and collagen content.
80% Polyglycerol(sebacate)-methacrylate (PGSM) polymer is used for making ECM-based scaffolds as it is biocompatible and biodegradable. 1x105 cells of dermal fibroblasts were seeded on PGSM scaffolds. Sugar-leached and emulsion templating fabrication techniques were compared. Scaffold surfaces were modified by exposure to either Ar or O2 plasma. After three weeks of cell culture, the scaffolds were analysed using resazurin and picrosirius red for cell proliferation and total collagen production, and the impact of different fabrication techniques and surface modifications compared. To investigate the effect of mechanical stimulation, the cell-seeded scaffolds were cultured in an Ebers TC-3 bioreactor. The regimes used either short(10 s stimulation, 30 s rest) or extended (2 h stimulation, 6 hours rest)stimulation and resting periods in combination with 5 or 10% tensile strain. All the regimens used in the experiments had the same total stimulation time, with strain applied at 1 Hz. After two weeks of stimulation, the scaffolds were analysed with resazurin, picogreen, and picrosirius red for cell proliferation and collagen content. 3D static controls had the same number of cells on scaffolds that were not exposed to strain.
80% PGSM scaffolds fabricated by emulsion templating induced higher cell proliferation and collagen production than sugar-leached scaffolds. However, there was no significant difference between surface treatments when compared with the same fabrication technique. Therefore emulsion templating and O2 plasma treatment was used to generate the scaffolds for the remainder of the study Mechanical stimulation results show that with longer active and resting periods, in combination with 10% tensile strain, the cells generated more collagen. However, this regime showed no significant impact on cell proliferation when compared to unstimulated cells. However, shorter stimulation and rest periods, together with 5% tensile strength resulted in significantly greater cell proliferation, but no significant difference in terms of total collagen when compared to results from unstimulated scaffolds.
Mechanical stimulation has been shown to influence the ECM secretion from cells in vitro. To be able to obtain the highest amount of collagen from cells in vitro, the appropriate scaffold and mechanical regime are necessary. It is suggested that one regime can only promote one aspect. A combination of two regimes will be tested as the next step to enhance both cell proliferation and collagen production.
62825437684
