title: Photo-immobilization of epidermal growth factor enhances its mitogenic effect by artificial juxtacrine signaling.
abstract: Photo-reactive epidermal growth factor (EGF) was synthesized by coupling EGF with azidobenzoic acid and was immobilized onto the wells of a polystyrene culture plate by photo-irradiation. The photo-immobilized EGF enhanced the growth of anchorage-dependent cells more than native or azidobenzoyl derivatized EGF. A small amount of photo-immobilized EGF was sufficient to enhance the growth of cells and the maximal mitogenic effect was greater than that of native or derivatized EGF. On the other hand, the photo-immobilized EGF did not enhance growth of anchorage-independent cells. In addition, signal transduction in the cells adhered only on the EGF-immobilized surface was observed by staining of phosphotyrosine residues by anti-phosphotyrosine antibodies. These results showed that the enhanced cell growth was due to direct interaction between the cells and the immobilized EGF. Photo-immobilization could be a universal means of fixing growth factors onto an artificial matrix that is devoid of chemically functional groups scaffolding growth factors and could provide a new tool to elucidate signal transduction mechanism and could lead to the development of a new protein-free cell culture system or tissue engineering materials.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Japan.
authors.forename: G
authors.initials: G
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: Y
authors.initials: Y
authors.lastname: Imanishi
mesh_terms: D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D004815:Epidermal Growth Factor / Q000737:chemistry / Q000494:pharmacology / Q000528:radiation effects*; D051379:Mice; D008856:Microscopy, Fluorescence; D008934:Mitogens / Q000494:pharmacology*; D015398:Signal Transduction; D014466:Ultraviolet Rays
chemical_list: D008934:Mitogens; D004815:Epidermal Growth Factor