Event Abstract Back to Event Multifunctional Fibrin/PEG hydrogels for the cardiac differentiation of reprogramed amniotic fluid derived stem cells for congenital heart repair Christopher Tsao1, Laura Pandolfi2, Ennio Tasciotti2 and Jeffrey G. Jacot1, 3 1 Rice University, Bioengineering, United States 2 Houston Methodist Research Institute, Regenerative Medicine, United States 3 Texas Children's Hospital, Congenital Heart Surgery Service, United States Introduction: Congenital heart defects are the most common type of birth defect and the leading cause of infant death. Current repair strategies involve surgical operations and the use of fixed autografts and homografts, which inevitability require repeat surgeries due to their inability to grow with the patient and a mechanical mismatch with native tissue. Congenital heart defects can be detected by prenatal ultrasound as early as the first trimester. The most severe defects will require surgical intervention soon after birth. This time between diagnosis and surgery can effectively be used to engineer functioning cardiac tissue. The goal of this study is to create an autologous, implantable cardiac patch that promotes the differentiation of reprogrammed human amniotic fluid derived stem cells (AFSC). Materials and Methods: Cell source: AFSCs were attained from amniotic fluid by routine amnioreduction. Stem cells were isolated and sorted for cKit+ and reprogrammed through mRNA transfection of Yamanaka factors. Mesoporous Silica Vectors (MSV): MSV (1µm in diameter; 51% of porosity) were loaded with GSK-3 and Wnt inhibitors separately and encapsulated in PLGA microspheres by solid-oil-water (S/O/W) emulsion method. PLGA thickness is altered to tune release mechanics. The release of GSK-3 and Wnt inhibitors from PLGA-MSV, in vitro, was performed in PBS (37oC, under mild agitation). Samples were collected up to 2 weeks. Fibrin/PEG hydrogel: Fibrin/PEG hydrogels are formed by dissolving fibrinogen was combined at a 1:1 ratio with a bi-functional NHS poly(ethylene glycol) (PEG). After conjugation, reprogrammed AFSC with MSV were mixed into the solution. Thrombin was combined with the cell solution at a 1:4 ratio to initial fibrinogen. Cells within hydrogels were maintained in pluripotent stem cell media for 3 days and assessed for embryonic pluripotency markers. Directed cardiac differentiation of reprogrammed AFSCs was accomplished by MSV release of small molecules inhibiting the GSK3/Wnt signaling pathways. Results and Discussion: AFSC 3 days after seeded into fibrin/PEG hydrogels maintain viability and markers of pluripotency Oct4, TRA-1-81 (Fig 1). Preliminary release studies of GSK3 containing MSV show delayed release characteristics from different formulations of the hydrogel and vectors (Fig 2). Differentiation studies within fibrin/PEG hydrogels loaded with nanoparticles show an increase in brachyury expression day 1 after the start of differentiation suggesting mesendoderm lineage. With further inhibition of the Wnt signaling pathway, encapsulated cells express early cardiac markers Nkx2.5 and Isl-1. Conclusions: The current study shows potential for a completely autologous cardiac tissue patch for the repair of congenital heart defects. Successful reprogramming and differentiation of AFSCs proves that functional cardiac cells can result from amniotic fluid. Reprogrammed AFSCs in 3D show that pluripotency is maintained and directed cardiac differentiation can occur by delivery vectors releasing small molecules of the GSK3/Wnt inhibitory molecules. Rodrigo Ruano Keywords: Regenerative Medicine, Tissue Engineering, stem cell, MYOCARDIAL TISSUE Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: General Session Oral Topic: Biomaterials in constructing tissue substitutes Citation: Tsao C, Pandolfi L, Tasciotti E and Jacot JG (2016). Multifunctional Fibrin/PEG hydrogels for the cardiac differentiation of reprogramed amniotic fluid derived stem cells for congenital heart repair. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.02465 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Christopher Tsao Laura Pandolfi Ennio Tasciotti Jeffrey G Jacot Google Christopher Tsao Laura Pandolfi Ennio Tasciotti Jeffrey G Jacot Google Scholar Christopher Tsao Laura Pandolfi Ennio Tasciotti Jeffrey G Jacot PubMed Christopher Tsao Laura Pandolfi Ennio Tasciotti Jeffrey G Jacot Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.