Nanotechnology-based cell sheet engineering for regenerative medicine

In order to avoid several complications resulted from biodegradable scaffolds or single cell injection, we have developed "cell sheet engineering" by utilizing nanotechnology-based temperature-responsive culture dishes. Since temperature-responsive polymers are covalently grafted on the dishes, various types of cells adhere and proliferate on them at 37 degrees C, but are spontaneously detached only by reducing temperature below 32 degrees C without any need for proteolytic enzyme. All the confluent cells are noninvasively harvested as a single contiguous cell sheets with intact cell-cell junctions and deposited extracellular matrix. We have utilized these harvested cell sheets for various tissue reconstruction including ocular surfaces, periodontal ligament, cardiac patches as well as bladder.