Poly(N-isopropylacrylamide)-grafted gelatin as a thermoresponsive cell-adhesive, mold-releasable material for shape-engineered tissues

Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) can be used as a thermoresponsive cell-adhesive matrix and mold-releasable material for shape-engineered tissues. An example of such a tissue with predetermined shape is realized by fabrication of a tubular endothelial cell construct. A solution containing a mixture of PNIPAM-gelatin and PNIPAM was coated on the luminal surface of a glass capillary tube. After air-drying, endothelial cells were seeded and cultured for four days at 37 degrees C. The infusion of the culture medium into the tube at 20 degrees C resulted in the spontaneous detachment and removal of a tubular vascular tissue composed of endothelial cells and supramolecularly organized extracellular matrices produced by endothelial cells on the basal side of the tissue. The potential use of a thermoresponsive cell-adhesive and mold-releasable material in complex-shaped tissue-engineered devices is discussed.