Monday, October 2, 2017 at 9:00am
Protein-based Biomaterials for Stem Cell Differentiation and Surgical Adhesive Applications
For tissue engineering applications, our lab is developing protein-based biomaterials to promote mesenchymal stem cell differentiation towards particular cell fates (e.g., bone or cartilage). We have genetically engineered modular proteins containing peptides containing growth factors and have designed proteins that can respond to environmental changes (e.g., temperature or pH). Overall, our work demonstrates that bioactive cues based on peptides or proteins can successfully promote adult stem cell differentiation to desired lineages.
For surgical adhesive applications, we designed protein-based adhesives containing two domains: a structural domain that provides flexibility and an adhesive domain that provides the ability to adhere in wet environments. Our material demonstrates high cytocompatibility (>98% viability) and significant bulk adhesive strength when dry (approximately 1 MPa). Furthermore, due to coacervation that occurs at physiological conditions, the material can easily be applied underwater and provides the strongest bonds of any rationally designed protein when used completely underwater. The unique properties of this new family of materials are ideal for application as a soft tissue surgical adhesive, as well as coatings for cell attachment or scaffolds for tissue engineering.
Julie Liu received her B.S.E. in chemical engineering from Princeton University. She was awarded a Whitaker Graduate Fellowship and worked with David Tirrell at the California Institute of Technology. Her doctoral research examined the cellular response to protein-based matrices designed for small-diameter vascular grafts. After obtaining her Ph.D. in chemical engineering, she received an NIH postdoctoral fellowship to study skeletal biology with Jane Lian and Gary Stein in the department of cell biology at the University of Massachusetts Medical School. She is an associate professor of chemical engineering and biomedical engineering at Purdue University. Her research interests include biomimetic materials, tissue engineering, stem cell differentiation, surgical adhesives, and detection of epigenetic modifications. Her research has been funded by the National Science Foundation, National Institutes of Health, Department of Defense, American Heart Association, and a 3M Nontenured Faculty Award.