Spray‑On Immune Shield Coating Protects Transplanted Organs Without Systemic Immunosuppression

A recent advance from Pohang University of Science and Technology (POSTECH) and Ewha Womans University in Korea introduces a spray‑on coating that adheres directly to transplanted organs and delivers immunosuppressive drugs locally, offering a potential way to reduce or even eliminate the need for lifelong systemic immunosuppressants. Organ transplantation remains the most effective treatment for organ failure, yet patients must take continuous immunosuppressive medication to prevent rejection. These drugs circulate throughout the body and can cause serious side effects, including kidney toxicity and heightened infection risk. The research team set out to solve this long‑standing problem by shifting immunosuppression from a whole‑body approach to a targeted, organ‑specific strategy.

The technology, called “Immune‑Shield”, uses microgels made from mussel‑derived adhesive proteins that can stick firmly to wet biological surfaces. When sprayed onto an organ, the microgels form a thin, invisible coating that remains in place and slowly releases immunosuppressive drugs directly where they are needed. This approach ensures that the medication acts at the transplant site rather than dispersing through the bloodstream. The team demonstrated that the coating adheres reliably even on complex organ geometries, a key requirement for practical surgical use.

In xenotransplantation experiments, Immune‑Shield significantly reduced immune cell infiltration and inflammatory responses, extending the survival of transplanted tissues. The localized delivery produced more than double the immunosuppressive effect of conventional systemic drug administration, highlighting the efficiency of site‑specific dosing. Because the coating keeps the drug concentrated at the organ surface, it minimizes exposure to the rest of the body, potentially reducing the severe side effects that currently burden transplant recipients.

The researchers emphasize that the mussel‑inspired adhesive protein is a uniquely effective biomaterial for this purpose, capable of forming stable bonds in wet environments where most adhesives fail. They also note that the spray method is simple to apply during surgery and could be adapted to a wide range of transplanted tissues. The team envisions Immune‑Shield as a foundational technology for improving outcomes in xenotransplantation and human organ transplantation by increasing graft survival while reducing patient risk.

By creating a coating that delivers immunosuppressants exactly where they are needed, the POSTECH and Ewha researchers have introduced a promising strategy for overcoming one of transplantation’s most persistent challenges. The work points toward a future in which patients may no longer need lifelong systemic immunosuppression, improving safety, quality of life, and long‑term transplant success.