EXOSMART · Exosome-Based Smart Coatings for Improved Bone Healing in Orthopaedic Implants

Every year millions of Europeans receive orthopaedic implants such as hip and knee prostheses. While these restore mobility, up to 20% fail within 10 years mainly because of chronic inflammation. Each revision surgery costs an average of €45,000, causing suffering for patients and creating an annual burden of more than €2 billion on EU healthcare. The key reason for implant failure is uncontrolled inflammation in the immediate postoperative period (48–72hours). During this short period immune cells called macrophages must switch from a pro-inflammatory state (M1) to a pro-healing state (M2). Current implant technologies cannot guide this transition with the required timing.EXOSMART addresses this challenge by creating smart implant coatings that release healing signals precisely when they are needed. The project harnesses exosomes, tiny vesicles naturally secreted by cells that act as biological couriers. These vesicles are loaded with interleukin 4 (IL-4), a protein that calms inflammation and promotes the M2 state for bone repair. Three key innovations make this possible:-Engineering stem cells to produce IL-4 only under inflammatory conditions and harvesting their exosomes-Stabilising IL-4 inside exosomes to extend its bioactivity-Embedding these smart exosomes into layered titanium coatings for spatially and temporally controlled releaseThe project combines advanced bioengineering at Stanford (USA) with surface engineering expertise at UGent (Belgium). It will generate new knowledge on immune-instructive biomaterials and deliver the first timed, biologically triggered IL-4 delivery system.For Europe, EXOSMART tackles a major medical and economic challenge. For the host institution, it brings access to complementary approaches and international collaborations. For the researcher, the fellowship provides cutting-edge expertise, fosters independence and builds a transatlantic network, laying the foundation for an independent career in biomedical innovation.