g-Jin Seo

Xyloglucan as a synthetic extracellular matrix for hepatocyte attachment.

The possibility of employing naturally derived xyloglucan (XG) having galactose moieties in the side chain for the development of synthetic extracellular matrix in tissue engineering was studied. Hepatocyte adhesion to the XG-coated polystyrene (PS) dish was 73.9% after 30 min incubation, whereas that to the PS dish as a negative control was 59.1%. The hepatocyte adhesion to the XG-coated surface was dependent on the presence of Ca2+ ions, whereas that to the XG-coated surface could not be induced by Mg2+ ions alone, indicating specific interaction between galactose moieties of XG and asialoglycoprotein receptors of hepatocytes. From the results of fluorescence, confocal laser micrographs and flow cytometry, it was suggested that XG was internalized by hepatocytes through a receptor-mediated mechanism. The DNA synthesis of hepatocytes attached to the XG-coated surface was decreased with an increase of the coating concentration of XG and in the presence of epidermal growth factor (EGF). The spreading shapes of the hepatocytes attached to the surface in the presence of EGF at low concentration of XG (1 μg/ml) were enhanced. The hepatocytes attached to the surface at a high concentration of XG (200 μg/ml) showed round shapes with spheroids after 16 h in the presence of EGF.

Controlled release of epidermal growth factor (egf) from egf-loaded polymeric nanoparticles composed of polystyrene as core and poly(methacrylic acid) as coronain vitro

Polymeric nanoparticles composed of polystyrene (PS) as core and poly(methacrylic acid) (PMA) as corona were prepared by the dispersion copolymerization. The potential of the nanoparticles as carriers for recombinant human epidermal growth factor (EGF) was investigated. The nanoparticles showed monodispersity and good water-dispersibility. The loading content of EGF to the nanoparticles was very high due to electrostatic interaction between EGF and nanoparticles. EGF was released as a pseudo-zero order pattern after initial burst effect. The nanoparticles were sufficient for A431 cells proliferation.