Colin J. Weber, MD, DMSc - Basic Science Research Faculty

Colin J. Weber, MD, Dm, Sci

William McGarity Professor of Surgery
Department of Surgery
General and Endocrine Surgery
Emory University School of Medicine

Dr. Weber’s research focus is pancreatic islet transplantation. The long-term goal is to develop techniques for safe and durable islet cell replacement for large numbers of patients with insulin dependent diabetes mellitus. For the past several years, this research has concentrated on the use of xenogeneic tissues as sources of donor islets and microencapsulation plus selective immune modulation of hosts as the means to accomplish cross species islet graft survival.

Working with Dr. Susan Safley, Dr. Weber and Dr. Safley have focused on the NOD mouse which develops diabetes spontaneously in a manner quite similar to type I diabetes in patients. They have found that spontaneously diabetic NOD recipients reject both isologous, allogeneic, and xenogeneic islets very rapidly, but that microencapsulation of these islets prolongs their survival dramatically.  In addition, Dr. Safley and Dr. Weber have learned that the NOD immunologic response to allogeneic and xenogeneic islets is primarily orchestrated by the host NOD mouse CD4+ T-cell. Interference with the activation of CD4+ T-cells by the imposition of co-stimulatory blockade agents given to recipients of encapsulated porcine islet xenografts dramatically prolongs their survival to >1 and ½ years.

In addition in the past year, Drs. Weber and Safley have developed and improved formulation of microcapsules which is both more immuno-protective and durable allowing the long term application of this technique to islet transplantation. The results of these studies have culminated in a research proposal to test these concepts in diabetic non-human primates in the coming year. Furthermore, Drs. Weber and Safley are studying a humanized Scid mouse with diabetes which can receive both porcine and human islets and human peripheral blood mononuclear cells PVMs in order to assess human immune reactions responses to islet grafts in vivo. /P>

Recent Publications (2007 – 2008)

  • Cardona K,  Milas Z, Strobert E, Cano J, Jiang W, Safley SA, Gangappa S, Hering BJ, Weber CJ, Pearson  TC, Larsen CP. Engraftment of Adult Porcine Islet Xenografts in Diabetic Nonhuman Primates Through Targeting of Costimulation Pathways.  American Jn. of Transplantation, April 2007, 7:1-9.  
  • Safley SA, Cui H, Cauffiel S, Weber CJ. Biocompatibility and immune acceptance of ault porcine islets transplanted IP in diabetic NOD mice in calcium alginate PLL microcapsules versus barium alginate microcapsules without PLL.  Jn of Diabetes Science and Technology.  In press.  August 2008.