Cell-intrusive Biomaterials for Tissue Regeneration & Delivery of Therapeutics
Dr. Melissa Krebs, Assistant Professor of Chemical & Biological Engineering
Colorado School of Mines
ABSTRACT: What do eyes, cartilage, bone, and teeth have in common? They are very different types of tissues, but in each, cells are distributed within an extracellular matrix (ECM) environment that provides rich chemical, mechanical, and architectural cues to the cells to direct their appropriate behavior for their tissue type. Biomaterials are being heavily investigated for use as tissue scaffolds and bioactive factor delivery systems with applications in tissue regeneration. Our group seeks to develop biopolymer systems that enhance our understanding of cells’ interactions with their microenvironment and that can be used for regenerative medicine applications. This presentation will highlight our work in three distinct areas: (1) new biopolymer technologies for glaucoma drug screening, (2) cartilage regeneration, and (3) bone and dental tissue regeneration. (1) The trabecular meshwork is an important filtering tissue within the eye that may play a role in glaucoma. We are engineering natural biopolymer scaffolds that mimic the ECM of this tissue, which can be used to determine the impact of the ECM chemistry, the architecture, rate of perfusion, and various drugs on trabecular meshwork cells that are cultured in this biomimetic environment. (2) Growth plate cartilage in children is fragile and prone to damage. We are engineering novel biopolymer systems to prevent bony bar formation in these injury sites and promote the regeneration of the growth plate cartilage tissue. These materials can provide sustained delivery of important soluble factors to the injured site, and we have been testing them in a rat growth plate injury model. (3) We are engineering materials with calcium phosphates that can be tuned to match a desired biological apatite, including those found in bone, dentin, and enamel. We have demonstrated the ability to fabricate composite materials with the mineral phase encapsulated within a polymeric hydrogel or as a surface coating, with the ability to control the thickness, location, morphology, and chemistry of the mineral phases. Our group is investigating the use of these materials as novel dental fillings and bone graft materials. In summary, we know that the cellular environment is critical for tissue engineering approaches, and our group seeks to enhance our understanding of these interactions while developing new regenerative technologies.