Preparation and Evaluation of Polymer Microspheres with Cell Adhesion Activity

Microspheres having cell adhesion activity were prepared by immobilizing a tetrapeptide Arg-Gly-Asp-Ser (RGDS) onto the surface. Phagocytosis of the microspheres by leukocytes was not enhanced by immobilizing RGDS, but specific oxygen consumption was observed during the incubation of the RGDS-carrying microspheres with leukocytes. This was enhanced by a spacer introduced between RGDS and the microsphere. These results suggested that the immobilized RGDS could transduce the adhesion signal, resulting in the activation of leukocytes without enhancing phagocytosis of the microspheres. Furthermore, it was found that soluble RGDS did not induce oxygen consumption at all by itself. This result suggests that RGDS must be immobilized on solid carriers for the specific activation of leukocytes. Preparation and Evaluation of Polymer Microspheres with Cell Adhesion Activity.