Researchers at the University of Iowa have created a bio patch to regenerate missing or damaged bone. The patch has been shown to nearly fully regrow missing skull, seen in the image above. Image courtesy of Satheesh Elangovan.
The team started with a collagen scaffold. The researchers then loaded the bio patch with synthetically created plasmids, each of which is outfitted with the genetic instructions for producing bone. They then inserted the scaffold on to a 5-millimeter by 2-millimeter missing area of skull in test animals. Four weeks later, the team compared the bio patch's effectiveness to inserting a scaffold with no plasmids or taking no action at all.
The plasmid does its work by entering bone cells already in the body – usually those located right around the damaged area that wander over to the scaffold. The team used a polymer to shrink the particle's size (like creating a zip file, for example) and to give the plasmid the positive electrical charge that would make it easier for the resident bone cells to take them in.
"The most exciting part to me is that we were able to develop an efficacious, nonviral-based gene-delivery system for treating bone loss," says Sheetal D'mello, a graduate student in pharmacy and a joint first author on the paper.
Contributing authors from the UI include Liu Hong, Deborah Dawson, Clark Stanford, and Georgia Johnson, all in dentistry, and Chantal Allamargot, from the UI's Central Microscopy Research Facility. Ryan Ross and D. Rick Sumner, from Rush Medical College, in Chicago, also contributed to the study and to the paper.
The International Team for Implantology, the National Cancer Institute at the National Institutes of Health (grant numbers: R21 CA13345 01 and R21 CA128414 01) and the American Cancer Society funded the research. The UI also supported the work through a start-up grant.