Scientists in Korea using a 3D printed drug microcarrier have shown in animal models that the carrier maintained robust integrity and delivered a local, sustained load of cyclosporine A (CsA) in an amount that overcame the need for additional drugs to treat immune rejection. The study (“3D printed drug/cell carrier enabling effective release of cyclosporine A for xenogeneic cell-based therapy”) will be published in a future issue of Cell Transplantation and is currently available on-line as an unedited early e-pub.

“Our objective was to show the feasibility of using a subcutaneous 3D printed drug delivery system to achieve local and sustained CsA release and to investigate the local immunosuppressive effects of the CsA after cell transplantation,” explained Dong-Woo Cho, Ph.D., of the department of mechanical engineering at the Pohang University of Science and Technology. “The improved load-bearing capacity of the combined microsphere and hydrogel system, and its ability to maintain its integrity and shape during the implantation period, helped to deliver a sustained CsA release, preventing the acceleration of the secretion of cytokines related to immune rejection.”

The researchers noted that many trials have attempted CsA delivery based on either microspheres or hydrogels, but most encountered serious problems, such as causing embolisms or organ damage due to migration of the microspheres from the injection site. Also, weak mechanical properties in many other kinds of systems caused premature dissolution and placed limitations on drug load quantity. However, the improved load-bearing capacity of the vehicles and improved structure that the Korean team developed allowed the sustained release of CsA at the desired site.

“This research could be a fundamental study for overcoming existing cell transplantation limitations, mainly caused by systemic immunosuppression,” wrote the investigators, who advocated 3D printing technology for a variety of medical applications, including printing membranes of various shapes.

Cell-based therapies often require the use of allogeneic or xenogenic cells that can stimulate an immune rejection response, requiring the use of immunosuppressive drugs to prevent acute transplant rejection. The introduction of CsA improves the success rate of transplantations, but systemic administration requires high doses of immunosuppressant that can have severe side effects. The benefit of their 3D printed combination microsphere and hydrogel carrier system is that it provides local rather than systemic drug delivery, say the researchers, noted Dr. Cho, adding that the carrier his team developed could be a promising solution to treating several diseases that require cell-based therapy, such as muscular dystrophy, degenerative disc disease, or myocardial infarction.