Temperature-induced cell detachment on immobilized pluronic surface.

The Pluronic F68 and F127, a triblock copolymer of ethylene oxide and propylene oxide, was activated using carbonyldiimidazole (CDI), and CDI-activated Pluronic F68 and F127 was subsequently immobilized on the surface of a poly-L-lysine-coated polystyrene tissue culture flask. Cell culture was performed on the Pluronic-immobilized flask. The morphology of fibroblasts (L929 cells) on the Pluronic F127-immobilized flask was mainly spherical, and showed less spreading behavior than that on the Pluronic F68-immobilized flask and conventional tissue culture flask. This observation indicates that L929 cells on Pluronic F127-immobilized flasks were cultured in a bio-inert environment. L929 cells were successively detached from both Pluronic F127-immobilized flask and Pluronic F68-immobilized flask by cooling the flask to 4-15 degrees C. This detachment is due to the hydration and dehydration properties of Pluronic, depending on the temperature. Umbilical cord blood was cultured in the Pluronic F127-immobilized and conventional polystyrene tissue culture flasks at 37 degrees C. The expression ratio of surface markers on hematopoietic stem cells (CD34 and CD133) cultured in the Pluronic F127-immobilized flask was significantly higher than that of the cells in polystyrene tissue culture flask.