Self-Assembling Nanofiber Spheres Act as Cell Carriers in Tissue RepairSelf-Assembling Nanofiber Spheres Act as Cell Carriers in Tissue Repair

A team of researchers at the University of Michigan (Ann Arbor) has developed nanofibrous hollow microspheres that self-assemble from star-shaped biodegradable polymers. Serving as cell carriers, the nanofiber spheres can be injected into the body to facilitate cartilage repair and regeneration.

To create the delivery system, the researchers took a biomimetic approach, employing biodegradable nanofibers to design a synthetic cell matrix that mimics a natural one. The hollow spheres are first combined with chrondrocytes and then injected into a wound. Because of their highly porous construction, the self-assembled nanofibrous microspheres allow nutrients to easily enter the cell carrier and provide an environment in which the cells can thrive once inside the body, according to the researchers. As the microspheres biodegrade in the body, they generate minimal byproducts that could be detrimental to the carried cell.

These porous, biodegradable microspheres demonstrated better efficacy than the traditional cell matrix used in tissue growth, the researchers state. They report three to four times more cartilage regeneration than observed with the control microsphere group as well as a higher quality of regeneration. Furthermore, this type of extracellular-matrix-mimicking architecture was not previously injectable for cell delivery to complex-shaped wounds, according to the scientists. Their research is detailed in a recent issue of the journal Nature Materials.