Di-functionalized hyaluronic acid with reactive thiol and azide groups for the neural differentiation of mouse embryonic stem cells

Event Abstract Back to Event Di-functionalized hyaluronic acid with reactive thiol and azide groups for the neural differentiation of mouse embryonic stem cells Hyun Ju Lim1, 2, Thuduwage H. Perera1, 2, Sukhen Ghosh3, Ali Azhdarinia3 and Laura Smith Callahan1, 2, 4 1 University of Texas Medical School at Houston, Department of Neurosurgery, United States 2 University of Texas Health Science Center, Center for Stem Cells & Regenerative Medicine, United States 3 University of Texas Medical School at Houston, Center for Molecular Imaging, United States 4 University of Texas Medical School at Houston, Department ofNanomedicine & Biomedical Engineering, United States Introduction: The native extracellular matrix (ECM) has a complex composition. Tissue engineering matrices need to possess multiple bioactive signaling molecules in order to adequately mimic the ECM. In the central nervous system, hyaluronic acid (HA) is a regulator of cellular migration, proliferation, differentiation, and angiogenesis. In these experiments, a di-functional HA (diHA), which possesses thiol and azide groups for tethering of bioactive molecules at independent concentrations, is characterized to and initial biological testing is conducted on the unfunctionalized materials using mouse embryonic stem cells (mES). Material and Methods: 60,000 kDa HA was functionalized to create diHA and methacrylated HA (mHA). The thiol group on di-HA was characterized using 1H-NMR, and 2,4,6-trinitrobenzene sulfonic acid (TNBS) assay. The azide group was characterized using 13C-NMR, Fourier transform infrared spectroscopy (FT-IR) spectrum, and radioTLC of 68Ga chelating agent binding. Photopolymerized hydrogels of diHA and mHA of varying compositions ratios were fabricated using Irgacure 2959 and 2.3 mJ cm-2 UVA light for 5 min. The swelling ratio, water contents, and mechanical properties (young’s and shear modulus) of 1:2 (diHA: mHA) and 1:5 (diHA: mHA) hydrogels was determined. D3 mES were encapsulated in the HA hydrogel at a density of 1 X 106 cells/mL. mES in 3D HA hydrogels were examined proliferation and differentiation potential by MTT assay and b-tubulin III (TUJ1) staining, respectively. Results Discussion: On 1H-NMR, the thiol peak was observed at 2.9 ppm for thiol functionalized samples with and without azide functionalization. A positive staining for thiol was also observed by TNBS assay for these sample groups. An azide peak was observed at 2096 cm-1 on the FT-IR spectrum (Figure 1), and at 50.1 ppm on the 13C-NMR spectrum for only HA samples functionalized with both thiol and azide groups. The average number of chelating moieties capping the azide group in HA was 3.9 ± 0.09 on radio TLC for diHA samples. A higher ratio of mHA (1:5) increased the young’s modulus, shear modulus, swelling ratio, and water content, significantly. Encapsulated mES were proliferated on 1:2 and 1:5 ratio of diHA:mHA hydrogel. After 3 and 6 days of differentiation, 44%±7% and55%±12% of mES in 1:2 (diHA: mHA) hydrogels expressed TUJ1, respectively. While mES in 1:5 (diHA: mHA) hydrogels expressed 39%±20% and 40%±14% after 3 and 6 days of differentiation, respectively (Figure 2). mES cultured in 1:2 (diHA: mHA) showed mature neural extension on day 6 of differentiation. Conclusion: These results indicate that thiol and azide groups were present on the modified HA backbone. Encapsulated mES were able to proliferate and differentiate in base matrix without additional bioactive signaling. diHA is a valuable tool to enhance bioactivity and control of bioactive signal concentrations in HA matrices developed to treat central nervous system injuries. The Bentsen Stoke Center University of Texas Medical School at Houston; William Stamp Farish Fund Keywords: Hydrogel, stem cell, Functionalization, matrix-cell interaction Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Biomimetic materials Citation: Lim H, Perera TH, Ghosh S, Azhdarinia A and Smith Callahan L (2016). Di-functionalized hyaluronic acid with reactive thiol and azide groups for the neural differentiation of mouse embryonic stem cells. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01762 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 Hyun Ju Lim Thuduwage H Perera Sukhen Ghosh Ali Azhdarinia Laura Smith Callahan Google Hyun Ju Lim Thuduwage H Perera Sukhen Ghosh Ali Azhdarinia Laura Smith Callahan Google Scholar Hyun Ju Lim Thuduwage H Perera Sukhen Ghosh Ali Azhdarinia Laura Smith Callahan PubMed Hyun Ju Lim Thuduwage H Perera Sukhen Ghosh Ali Azhdarinia Laura Smith Callahan 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.