An Injectable Hydrogel Bioimplant Loaded with Engineered Exosomes and Triple Anti-Tuberculosis Drugs with Potential for Treating Bone and Joint Tuberculosis

Purpose Treatment for bone and joint tuberculosis (BJTB) is challenging due to its refractory and recurrent nature. This study aimed to develop a bioimplantable scaffold with osteoinductive and antituberculosis characteristics to treat BJTB. Methods This scaffold is built on oxidized hyaluronic acid and carboxymethyl chitosan hydrogel mixed with hydroxyapatite as a bone tissue engineered material. In order to make the scaffold have the biological activity of promoting tissue repair, the engineered exosomes (Exo eng ) were added innovatively. In addition, drug-loaded liposomes equipped with an aldehyde group on the surface are cross-linked with the amine group of the hydrogel skeleton to participate in the Schiff base reaction. Results The designed scaffold has characteristics of self-healing and injectability exhibit excellent anti-tuberculosis and promoting bone repair activities. Exo eng strongly stimulates cellular angiogenesis and osteogenic differentiation. The liposomes coated in hydrogel can release three kinds of anti-tuberculosis drugs smoothly and slowly, achieving a long term anti-tuberculosis. Conclusion The composite bio-scaffold shows good tissue repair and long-term anti-tuberculosis abilities, which expected to provide a viable treatment plan for bone-related BJTB.