Researchers at the University of Iowa have created a bio patch to regenerate missing or damaged bone by putting DNA into a nano-sized particle that delivers bone-producing instructions directly into cells.

The bone-regeneration kit relies on a collagen platform seeded with particles containing the genes needed for producing bone. In experiments, the gene-encoding bio patch successfully regrew bone fully enough to cover skull wounds in test animals. It also stimulated new growth in human bone marrow stromal cells in lab experiments.

The study is novel in that the researchers directly delivered bone-producing instructions (using piece of DNA that encodes for a platelet-derived growth factor called PDGF-B) to existing bone cells in vivo, allowing those cells to produce the proteins that led to more bone production. Previous attempts had relied on repeated applications from the outside, which is costly, intensive, and harder to replicate consistently.

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-seeded bio patch grew 44-times more bone and soft tissue in the affected area than with the scaffold alone, and was 14-fold higher than the affected area with no manipulation. Aerial and cross-sectional scans showed the plasmid-encoded scaffolds had spurred enough new bone growth to nearly close the wound area, the researchers report.

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 researchers also point out that their delivery system is nonviral. That means the plasmid is less likely to cause an undesired immune response and is easier to produce in mass quantities, which lowers the cost.

The researchers next hope to create a bio platform that promotes new blood vessel growth– needed for extended and sustained bone growth.

This story is reprinted from material from University of Iowa, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.