Project Summary/Abstract Within the biomedical field there is great effort to study a multitude of cell processes, including cell-cell communication, cell-matrix interactions, cell signaling, pharmacological effects, and differentiation to name a few. It is widely known that the more closely the cell culture system replicates the native cellular environment, the more closely the cultured cells will model their native behaviors. Knowing this, over the years, various forms of three-dimensional culture strategies have emerged as a superior advancement over 2D culture. The most promising approaches include those that mimic the native extracellular matrix, in its architecture, mechanics, and composition, thereby providing the ideal biological signaling and cellular recognition sites that promote normal cell behavior. Towards this goal, the focus of this technology development proposal is to develop a tunable, bioactive, DNA-based hydrogel platform that can meet these tissue specific requirements and serves to advance in vitro cell culture. This material technology is significant because the DNA-based hydrogel platform eliminates the need for complex chemical interactions and takes advantage of the rapid self-assembly and spontaneous fibril formation that occurs when DNA is complexed with ECM protein collagen. In addition, this platform utilizes functional DNA aptamers to render the hydrogel bioactive. This technology is poised to promote cellular functions that are more native and reproducible to a broad community of biomedical researchers. To achieve our goals, the aims of our project are 1) Examine to bulk material properties achievable with DNA- collagen based hydrogels; and 2) Functionalize DNA-hydrogels with bioactive DNA aptamers. Our studies will be compared to commonly used hydrogels and we will demonstrate biological impact through validation studies. Completion of the above-described aims is expected to reveal the full breadth and potential of DNA-collagen based materials to mimic tissue specific ECM and serve as a material platform for a broad array of biomedical studies. We intend to develop a library of DNA-collagen bulk matrix with well-defined synthesis conditions capable of tunable mechanical properties and bioactivity for a range of cell responses involved cell-cell interactions, cell-matrix interactions, pharmacological studies, modelled health or disease states of cells, mechanistic insight into varied cell phenotypes, stem cell studies, and an array of other fundamental studies of tissue specific cell behaviors.

Project Narrative The ability to study native behaviors of cells is critical to biomedical and biological studies aimed at understanding cellular functions such as those found in disease states. This ability is best met through the use of culture matrices that mimic the cellular recognition sites and signaling that exists in native extracellular matrix (ECM). This proposal seeks to develop a DNA-based hydrogel platform with tunable features that recapitulates native ECM to support studies that aim to increase our understanding of the principles, mechanisms, and processes that underlie the health or dysfunction of tissue specific cells.