title: Preparation of collagen/gelatin sponge scaffold for sustained release of bFGF.
abstract: Artificial dermis (AD) has been used to regenerate dermis-like tissues in the treatment of full-thickness skin defects, but it takes 2 or 3 weeks to complete dermal regeneration. Our previous study demonstrated that injection of basic fibroblast growth factor (bFGF)-impregnated gelatin microspheres (MS) into the AD accelerates the regeneration of dermis-like tissue. However, injection of gelatin MS before clinical use is complicated and time consuming. This study investigated a new scaffold, in which collagen and gelatin are integrated, and which is capable of sustained bFGF release. We produced collagen/gelatin sponges with a gelatin concentration of 0wt%, 10wt%, 30wt%, and 50wt%. The mean pore size in each sponge decreased with the gelatin concentration. In an in vitro study, proliferation of fibroblasts in each sponge was not significantly different over 7 days of culture. As for in vivo sustained release of bFGF, a radioisotope study demonstrated that retention of bFGF in gelatin 10wt% and 30wt% sponges was significantly larger than that in gelatin 0wt% sponge. The collagen/gelatin sponges were grafted on full-thickness skin defects created on a rabbit ear, and we evaluated regeneration of dermis-like tissue by measuring the amount of hemoglobin and size of dermis-like tissue on histological sections. Seven days after implantation, the amount of hemoglobin in dermis-like tissue in gelatin 10wt% sponge was significantly larger than those in control and gelatin 50wt% sponge. Twenty-eight days after implantation, the area of dermis-like tissue in gelatin 10wt% sponge was significantly larger than those in the other specimens. We conclude that the collagen sponge integrated with 10wt% gelatin has the most potential for sustained release of bFGF and that the combination of collagen/gelatin 10wt% sponge and bFGF is a promising therapeutic modality for the treatment of full-thickness skin defects.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan. satoru@kuhp.kyoto-u.ac.jp
authors.forename: Satoru
authors.initials: S
authors.lastname: Takemoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Morimoto
authors.forename: Yu
authors.initials: Y
authors.lastname: Kimura
authors.forename: Tsuguyoshi
authors.initials: T
authors.lastname: Taira
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kitagawa
authors.forename: Kenji
authors.initials: K
authors.lastname: Tomihata
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
authors.forename: Shigehiko
authors.initials: S
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D049109:Cell Proliferation; D003094:Collagen / Q000737:chemistry*; D016222:Fibroblast Growth Factor 2 / Q000737:chemistry / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D005780:Gelatin / Q000737:chemistry*; D008297:Male; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D011817:Rabbits; D016038:Skin Transplantation / Q000379:methods; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D016222:Fibroblast Growth Factor 2; D005780:Gelatin; D003094:Collagen