Design and Characterization of Temporally Controlled Release Hydrogel System Towards Controlling Cellular Response

Extracellular matrix (ECM) is a highly complex environment that is composed of both structural and nonstructural components that can influence various biological activities, such as differentiation and proliferation. Given the importance of ECM in biological activities, it is critical to recapitulate its dynamic nature in both in vitro and in vivo environments for various applications from tissue engineering to organ-on-chip models. Hydrogel systems have emerged as potential methods to mimic the ECM due to its tunable mechanical properties and composition. However, hydrogel systems without specific modifications like a controlled release system are unable to replicate the temporal distribution of cytokines found in the native ECM environment. A potential solution is DNA nanotechnology, which allows for the creation of nanostructures that are highly programmable, actuatable with various stimuli, and orthogonal modification with multiplexing of biomolecules. Therefore, we utilized DNA nanotechnology tools, such as multiplex design and toehold-mediated strand displacement reaction, to design a highly tunable control release system with temporal precision and incorporated them within a gelatin-based hydrogel system to fabricate a dynamic hydrogel environment that can be used towards controlling cellular behavior. To achieve this objective, we designed a multi- way DNA nanostructure that was able to be multiplexed up to three different cargos and examined its potential to be used as a temporally controlled release system in both solution and in hydrogel systems. Furthermore, we studied the sequence design rules for toehold- mediated strand displacement reaction and modelled the release properties (quantity and rate) to enable us to further finetune the release profile of the system. Finally, we carried out the proof-of-concept study using our DNA controlled release system modified with biomolecules (TNF-⍺ or IFN-⍺) and it was incorporated within a gelatin methacrylate hydrogel system. Jurkat-Dual cells, a dual reporter gene cell line, were used to examine if this novel dynamic hydrogel system was able to stimulate them. Overall, this work paves the way to the development of novel tissue engineering scaffolds that use DNA nanotechnology to precisely control the temporal release of biomolecules, such as growth factors, cytokines, and chemokines, to further mimic the native ECM environment.

Author

• Hu, Chih-Hsiang

• Controlled release
• DNA nanotechnology
• Hydrogel
• Strand displacement reaction

Identifier

hdl:1920/14388

OAI identifier oai:identifier

oai:MARS:1920/14388