Abstract
In order to develop an effective organ/cell preservation method and to monitor/control post-transplant graft function continuously and non-invasively, an innovative optic technology to visualize/control cell/organ function seems to be useful. Recently, we have developed molecular probes to visualize redox states and cellular stresses, pH and cellular antigens in deeper lesions of the organ, and trying to activate intracellular key molecules by optical irradiation. In the hepatic ischemia/reperfusion model of mice, we successfully imaged liver oxidative stress and apoptosis by caspase-3 activity non-invasively and chronologically in a single mouse. We also developed a unique tool for visualizing intracellular pH and succeeded in imaging dynamic changes of pH in a mouse posterior limb ischemia/reperfusion model. Furthermore, we are now developing new tools to control intracellular molecules by blue light. We used plant-derived proteins to activate Akt/PKB molecule, essential for cell survival. By irradiating blue light, Akt in hepatocytes were phosphorylated(Ser and Thr)and activated. These tools will definitely provide a new avenue toward cell/organ transplantation in the future.