Self-assembling helical rosette nanotubes for cartilage tissue engineering

Today, one of the limitations associated with cartilage grafting is the lack of bonding between the implanted materials and the natural tissue. Helical rosette nanotubes (HRNs) are novel biomimetic self-assembled supramolecular structures whose basic building blocks are DNA base-pairs, which can solidify into a viscous gel at body temperatures in short periods of time. HRNs are similar in size to collagen in cartilage. In this study, the mechanical properties of select hydrogel/HRN composites were tested. In addition, electrospinning was used to generate three-dimensional, implantable, composite HRN fibers containing fibroblast-like type-B synoviocytes (SFB cells) or chondrocytes. Importantly, results showed that HRNs enhanced hydrogel adhesive strength to fractured collagen and created a scaffold with nanometer-rough surface structures that promoted SFB cell and chondrocyte adhesion and viability. In this manner, this study provided an alternative cartilage regenerative material produced by nanotechnology techniques that can be injected as a liquid, solidify at body temperatures under short periods of time, have suitable mechanical properties to cartilage, and promote SFB cell viability and adhesion.