AGRIPOLY:Development of biogenic thermoresponsive polyelectrolyte multilayers for culture of induced pluripotent stem cells

The aim of the research project is to develop an entirely new culture system that permits continuous culture and harvesting of iPSC on a thermoresponsive and bioactive culture substratum. This shall be achieved by the conjugation of the polycation chitosan with the thermoresponsive element PNIPAM and the use of bioactive polyanions heparin and chitosan for form multilayers of thickness of about 50 nm using LbL technique. A further novelty of the project shall the uploading of the mitogenic growth factor FGF-2 that will support proliferation of iPSC and maintenance of their stemness. Hence, the proposal has the following ambitious objectives: Grafting of PNIPAM to chitosan (CHI-PNIPAM) and study of thermoresponsive behavior depending on grafting degree (i), study of ability of CHI-PNIPAM to form multilayers with either heparin or chondroitin sulfate of the desired thickness (ii) thermoresponsive behavior of multilayers in the desired temperature range between 4 and 37°C (iii), ability of multilayers to adsorb proteins from serum or single protein solutions and support slight attachment of iPSC spheroids (iv), ability of multilayers to take up and present the growth factor FGF-2 in a bioactive manner (v) and support of iPSC proliferation and stemness (vi).