Micropatterned platelet lysate-based membranes for cell culture and cardiac regeneration

• Autor(a) principal: Figueiredo, Samuel Garrido
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/32854
• topic: Tissue engineering; Cardiac patches; Hydrogels; PLMA; Micropillars; Micropatterned surfaces; Microfabrication

Heart diseases are a major cause of dead worldwide. Myocardial infarction is one of the most serious problems, leading to the destruction of functional heart tissue and putting patients at constant risk of heart failure. Conventional pharmacologic therapies or organ transplantation are often not efficient and associated with multiple limitations, and therefore the search for other alternatives is a need. Tissue engineering (TE) has emerged as an alternative to produce structures that potentiate cardiac regeneration or microtissues development for in vitro drug screening. TE typically combines biomaterials, cells, and biochemical signals. The ideal 3D structure for a cardiac patch must combine several structural and functional properties that should match the existing in the native myocardium. Human methacryloyl platelet lysates (PLMA)-derived hydrogels have recently been reported as a human based biomaterial with tuneable mechanical properties that support human cell culture. In this thesis project, micropatterned PLMA-based hydrogels were developed. To do so, PLs were chemically modified with methacryloyl groups, thus becoming photocrosslinkable. Afterwards, polydimethylsiloxane (PDMS) was used to produce micropatterned structures with microwells to be used as counter molds. Two different micropillars patterns were made - hexagonal and square. Mechanical characterization shows that micropatterned PLMA hydrogels have mechanical properties dependent on the concentration of the polymer present in the precursor solution. Biological assays were performed in order to understand cells response to topography and results showed that PLMA-hydrogels support the adhesion and proliferation of both human umbilical vein endothelial cells (HUVECs) and myoblasts derived from embryonic myocardium rat tissue (H9c2(2-1)). In this work we were capable to produce micropatterned PLMA-hydrogels which have suitable biomechanical properties, allowing a good cell adhesion, proliferation, and pre-formation of a microtissue with potential crosstalk between cells at the scaffold.