title: Recombinant human gelatin substitute with photoreactive properties for cell culture and tissue engineering.
abstract: The human recombinant collagen I α1 chain monomer (rh-gelatin) was modified by the incorporation of an azidophenyl group to prepare photoreactive human gelatin (Az-rh-gelatin), with approximately 90% of the lysine residues conjugated with azidobenzoic acid. Slight changes in conformation (circular dichroism spectra) and thermal properties (gelation and melting points) were noticed after modification. Ultraviolet (UV) irradiation could immobilize the Az-rh-gelatin on polymer surfaces, such as polystyrene and polytetrafluoroethylene. Az-rh-gelatin was stably retained on the polymer surfaces, while unmodified gelatin was mostly lost by brief washing. Human mesenchymal cells grew more efficiently on the immobilized surface than on the coated surface. The immobilized Az-rh-gelatin on the polymer surfaces was able to capture engineered growth factors with collagen affinity, and the bound growth factors stimulated the growth of cells dose-dependently. It was also possible to immobilize Az-rh-gelatin in micropatterns (stripe, grid, and so on) using photomasks, and the cells grew according to the patterns. These results suggest that the photoreactive human gelatin, in combination with collagen-binding growth factors, will be clinically useful for surface modification of synthetic materials for cell culture systems and tissue engineering.
authors.affiliation: Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitajima
authors.forename: Sei
authors.initials: S
authors.lastname: Obuse
authors.forename: Takahiro
authors.initials: T
authors.lastname: Adachi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tomita
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ito
mesh_terms: D018929:Cell Culture Techniques; D024042:Collagen Type I / Q000737:chemistry*; D000090602:Collagen Type I, alpha 1 Chain; D005780:Gelatin / Q000737:chemistry*; D006801:Humans; D055668:Photochemical Processes; D011137:Polystyrenes / Q000737:chemistry; D011138:Polytetrafluoroethylene / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D023822:Tissue Engineering; D014466:Ultraviolet Rays
chemical_list: D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D011137:Polystyrenes; D011994:Recombinant Proteins; D005780:Gelatin; D011138:Polytetrafluoroethylene