Our laboratory research involves studies of gastric epithelial nbarriern function as well as the mechanisms of growth factor signal transduction on normal and cancerous gastric and colonic epithelial cells. We are also involved in examining the cell cycle of pancreatic islets and studying ways on how to immortalize pancreatic islets for transplantation studies. Specifically, we are pursuing three general research topics:
1. The early signal transduction mechanisms of H. pylori and EGF (epidermal growth factor) and TGFa (transforming growth factor-alpha) on normal and cancerous human gastric epithelial cells;
2. The study of the Calcium-sensing receptor (CaR) in normal and cancerous gastric and colonic cell growth.
3. Mechanisms of immortalization of pancreatic islets using E1A-retroviral mutants.
The principle model systems used in these studies are human epithelial cells isolated and cultured from normal and cancerous gastric and colonic tissues, and rat and human pancreatic islets. Methods of study include Western- and Northern-blotting, gene transfection techniques, intracellular Ca2 fluorescent measurements using a fluorimeter and Fura-2/Fluo-4, and electrophysiological measurements of cell monolayers using Ussing-chambered techniques. Information gathered by our studies will be helpful in understanding the fundamental molecular mechanisms of gastrointestinal growth and repair. In addition, understanding the cell cycle in pancreatic islets will also provide valuable information in the genetic engineering of immortalized pancreatic islets for clinical transplantation.
Personnel involved in this Research: Brett C. Sheppard, MD; Karen E. Deveney, MD; Donald D. Trunkey, MD; and Clifford W. Deveney, MD.