New findings from a transplant study led by scientists from the Diabetes Research Institute (DRI) at the Miller School and a DRI Federation center at Xiamen University in China showed that mesenchymal stem cells may replace a powerful anti-rejection drug in transplant recipients. The results of this pioneering study involving kidney transplant patients may fundamentally transform the future of clinical transplantation.
Patients undergoing a transplant routinely receive a regimen of immunosuppressive therapy to block the body’s immune system from rejecting the donor organ or cells. While these drugs have been shown to improve graft function and minimize rejection episodes, they increase the risk of dangerous side effects, including infections and organ toxicity. To eliminate these adverse effects, scientists at the DRI and collaborating centers worldwide have been investigating safer methods for preventing transplant rejection and have turned their attention to naturally occurring cells in the body that have immuno-modulatory properties, like mesenchymal stem cells.
A mesenchymal stem cell can differentiate into bone, cartilage, fat, and other body tissues. But the stem cells have also been found to have a number of other beneficial therapeutic properties, including their ability to modulate the immune system by inhibiting T-cell proliferation, eliminating graft-vs.-host disease, limiting cytotoxic inflammation, and stimulating vascularization, among other benefits.
“This study represents a first, important step toward the definition of cell-based strategies that will one day allow for transplantation without the need for life-long anti-rejection drugs,” said Camillo Ricordi, M.D. (pictured), director of the University of Miami Diabetes Research Institute and Cell Transplant Center, the Stacy Joy Goodman Professor of Surgery, Distinguished Professor of Medicine, and professor of biomedical engineering, and microbiology and immunology. “The worldwide collaborative strategy of the DRI Federation and The Cure Alliance has resulted in yet another small step forward in our worldwide cure-focused efforts, indicating safety and efficacy of a stem cell-based strategy toward reducing and eventually eliminating anti-rejection drugs. This is particularly important to the DRI mission, as transplantation without immunosuppression is a major goal in any strategy for transplantation of insulin producing cells and a requirement for becoming a reality for all patients with Type 1 or Type 2 insulin dependent diabetes.”
In this recent study, patients with end-stage renal disease received infusions of bone marrow-derived autologous mesenchymal stem cells together with either standard-dose or low-dose calcineurin inhibitors. The control group received an immunosuppression regimen consisting of anti-IL-2 receptor antibody plus standard-dose calcineurin inhibitors.
After 1 year post-transplant, the results of the study indicate that among the patients undergoing a kidney transplant, the use of autologous mesenchymal stem cells compared with the standard immunosuppressive therapy resulted in lower incidence of acute organ rejection, decreased risk of infection, and better kidney function.
“We reported on the first 12 months follow-up, which showed no adverse events associated with mesenchymal stem cell therapy,” said Antonello Pileggi, M.D., Ph.D., director of the Preclinical Cell Processing and Translational Models Program at the Cell Transplant Center of the DRI. “We will continue monitoring the patients in the study to assess the long-term effects on kidney transplant function and survival, as well as the safety of stem cell transplantation in this setting. Should long-term safety be confirmed, it may be valuable for improving transplantation outcomes while reducing the risks associated with anti-rejection drugs.”
“This collaboration was part of the ongoing global efforts of The DRI Federation and of The Cure Focus Research Alliance,” said Xiumin Xu, M.S., director of the China-U.S. Collaborative Human Cell Transplant Program at the DRI. “The opportunity to contribute these results obtained through the combined team efforts of Affiliated Fuzhou General Hospital of Xiamen University and DRI to a journal as high impact as JAMA represents an important achievement for the China-USA Collaborative Human Cell Transplant Program at the Cell Transplant Center of DRI.”
Illustration: University of Miami Miller School of Medicine.
University of Miami Miller School of Medicine News Release (03/20/12)
Abstract (The Journal of the American Medical Association; 307(11), 1169-1177 (2012))