Special Medical Engineering Seminar-Dr. Hirotake Komatsu
Bridging between clinic and engineering: development of oxygen-transporting mesh for cell transplantation
Cell transplantation has excellent treatment potential for restoring lost function by the transplanted cells with the desired function. Pancreatic islets, ~150 µm spherical micro-organs in the native pancreas containing insulin-producing beta cells, play a critical role in regulating glucose homeostasis. Currently, for diabetics who lost functional islets, islet transplantation is a clinical treatment option. However, the shortage of donors has limited the expansion of islet transplantation. Recently, stem cell-derived insulin-producing islet cells are rapidly emerging as an alternative source for islet replacement therapy.
Although the potential alternative islet source is encouraging, hypoxic condition at the transplantation sites is detrimental to post-transplant islet survival and leads to transplanted islet obliteration. Therefore, oxygenation of the islet graft has been explored to improve graft survival. However, there are significant obstacles to its clinical use, including a bulky implant device and the need to inject concentrated oxygen. To address these issues, our team (Komatsu laboratory at City of Hope and Tai laboratory at Caltech) developed an implantable ultra-thin oxygen-transporting mesh that delivers oxygen to the hypoxic graft site from ambient air by diffusion potential. A flexible, 25 µm-thick interconnected microcapillary Parylene mesh transports oxygen, as well as functions as a scaffold for islet graft. Notably, the concept of transporting oxygen using ambient air is advantageous over preceding approaches in its unlimited oxygen source and safety in clinical applications. We aim to further improve our strategy for the future clinical use of stem cell-derived insulin-producing islet cells to cure diabetes.
Hirotake Komatsu, M.D., Ph.D. is an Assistant Research Professor in Arthur Riggs Diabetes & Metabolism Research Institute at City of Hope. His long-term goal is to cure diabetes by cell replacement therapy to improve quality of life for patients with diabetes. Dr. Komatsu obtained M.D. in 2002, at Juntendo University, Japan. He has a long experience as a hepato-pancreato-biliary surgeon over 10 years, and during the period, he pursued a Ph.D. for training in basic research in molecular biology. He joined City of Hope in 2014, where clinical islet transplantation and translational research are actively performed. His expertise is derived from a broad training in medicine and basic research in the fields of pancreas surgery and pancreatic islet transplantation. Dr. Komatsu is a member of International pancreas and islet transplant association, and was elected as a member of Young investigator committee (2020 – current). He was awarded several research grants including NIH, Juvenile diabetes research foundation, and Nora Eccles Treadwell Foundation as a Principal Investigator.