(WHS-P18) RAPID FABRICATION OF POLYVINYL ALCOHOL HYDROGEL FOAMS WITH ENCAPSULATED MESENCHYMAL STEM CELLS FOR CHRONIC WOUND TREATMENT
Friday, May 17, 2024
7:30 AM – 5:00 PM East Coast USA Time
Purpose: The purpose of this study is to develop a tunable hydrogel platform with encapsulated mesenchymal stem cells to enhance chronic wound treatment.
Methods: We synthesized a thiol methacrylate polyvinyl alcohol (TPVAMA) hydrogel system based on the thiol-ene reaction between methacrylated PVA (PVAMA) and thiolated PVA (TPVA). We introduced porous structures into the hydrogels via a gas-blowing process to improve nutrient transfer and waste removal, which could support cell viability. In this process, sodium bicarbonate and citric acid were combined into the system to create carbon dioxide, which was trapped during hydrogel fabrication to form a porous structure. Also, methacrylated gelatin (GelMA) was added into the system to improve cell attachment. Cells were mixed into hydrogel solutions prior to fabrication to obtain porous, cell-laden hydrogels. We obtained a library of hydrogel samples to utilize for further characterization.
Results: Cytocompatibility tests showed that all TPVAMA hydrogels have cell viability >95%, demonstrating this system is suitable for cell growth. 3D microscale images exhibited that we successfully encapsulated cells into hydrogels with varied dimensions. Viability of encapsulated A375 cells was measured over 14 days using a Live/Dead assay. At 14 days, viability was significantly higher in porous hydrogels with GelMA (porous-TPVAGelMA) than corollary non-porous hydrogels with (TPVAGelMA) and without GelMA (TPVAMA), with viabilities of 95±3%, 84±8%, and 71±18%, respectively (n=3, p < 0.05). In the encapsulation of fluorescently labeled 3T3 fibroblasts, porous-TPVAGelMA showed a significant increase in the number of cells and cell spreading over 14 days compared with non-porous TPVAGelMA and TPVAMA controls. These results indicate that GelMA enhances cell proliferation and attachment, while porous structures aid in maintaining long-term cell viability. In degradation studies, hydrogels containing higher TPVA content degraded faster in hydrolytic and oxidative solutions. Thus, the degradation rate can be tuned based on the PVAMA and TPVA ratio, indicating that the hydrogel system could be designed to degrade after implantation while supporting healing.
Conclusion: These studies demonstrate that TPVAMA hydrogel foams are a potential platform for chronic wound dressings that are degradable, tunable, and suitable for cell encapsulation. Current work is focused on performing scratch assays and ex vivo pig skin experiments with encapsulated mesenchymal stem cell samples to observe the effects of the hydrogel system on healing processes.