Smart scaffolding that can guide cells, proteins and small-molecule drugs to make new tissue and repair damage inside the body is in the works at Rice University.
Scientists at Rice and the Texas A&M Health Science Center Baylor College of Dentistry received a $1.7 million, five-year grantfrom the National Institutes of Health (NIH) to develop a hydrogel that can be injected into a patient to form an active biological scaffold.
Rice bioengineer Jeffrey Hartgerink and co-investigator Rena D'Souza of Baylor won the grant to continue their groundbreaking work on self-assembling, multidomain peptide hydrogels that not only physically support but alsoencourage the growth of specific kinds of tissues.
Bioengineers use scaffolds to mimic the body's extracellular matrix, which supports the growth and maintenance of living cells. Synthetic scaffolds are used as frameworks to form replacement tissues and, perhaps someday, regenerate entire organs from a patient's own cells. Once their work is done, the scaffolds are designed to degrade and leave only natural, healthy tissue behind.
While much of the work to date has focused on creatingtissue in the laboratory for implantation, Hartgerink's aim is to inject scaffolds infused with living cells that will allow the repairs to happen inside the tissue's natural environment.
The peptides designed and prepared at Rice self-assemble into nanofibers that can be triggered to form a hydrogel. "We can then deliver cells, small-molecule drugs and proteins to bring everything together properly in one place," said Hartgerink, an associate professor of chemistry and of bioengineering at Rice. Hydrogels could be designed to interact with stem cells and "get them to do what we want them to do," he said.
Hartgerink and D'Souza, a professor in the Department of Biomedical Sciences at Baylor currently on aworking sabbatical at Rice's BioScience Research Collaborative, have been pursuing the project for five years. The NIH grant will allow them to focus on the regeneration of the dentin-pulp complex found inside every tooth. The pulp, D'Souza said, is the soft tissue in the roots and crown that keeps the tooth vital and responsive to injury. "If you have a toothache, it's the tissue that's inflamed and has no place to expand. That's why it hurts so much," she said.