title: Collagen vitrigel membrane useful for paracrine assays in vitro and drug delivery systems in vivo.
abstract: We previously succeeded in converting a soft and turbid disk of type-I collagen gel into a strong and transparent vitrigel membrane utilizing a concept for the vitrification of heat-denatured proteins and have demonstrated its protein-permeability and advantage as a scaffold for reconstructing crosstalk models between two different cell types. In this study, we observed the nano-structure of the type-I collagen vitrigel membrane and verified its utility for paracrine assays in vitro and drug delivery systems in vivo. Scanning electron microscopic observation revealed that the vitrigel membrane was a dense network architecture of typical type-I collagen fibrils. In the crosstalk model between PC-12 pheochromocytoma cells and L929 fibroblasts, nerve growth factor (NGF) secreted from L929 cells passed through the collagen vitrigel membrane and induced the neurite outgrowth of PC-12 cells by its paracrine effect. Also, the collagen vitrigel membrane containing vascular endothelial growth factor (VEGF) showed sustained-release of VEGF in vitro and its subcutaneous transplantation into a rat resulted in remarkable angiogenesis. These data suggest that the collagen vitrigel membrane is useful for paracrine assays in vitro and drug delivery systems in vivo.
authors.affiliation: Laboratory of Animal Cell Biology (currently, Transgenic Animal Research Center), National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan. t.takezawa@affrc.go.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Takezawa
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Aya
authors.initials: A
authors.lastname: Nitani
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Takayama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kino-Oka
authors.forename: Masahito
authors.initials: M
authors.lastname: Taya
authors.forename: Shin
authors.initials: S
authors.lastname: Enosawa
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000295:instrumentation*; D002454:Cell Differentiation; D024042:Collagen Type I / Q000378:metabolism* / Q000648:ultrastructure; D016503:Drug Delivery Systems / Q000295:instrumentation*; D008297:Male; D008567:Membranes, Artificial; D049329:Nanostructures; D018919:Neovascularization, Physiologic; D020932:Nerve Growth Factor / Q000378:metabolism; D016716:PC12 Cells; D019899:Paracrine Communication; D010539:Permeability; D019736:Prostheses and Implants; D051381:Rats; D017208:Rats, Wistar; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D024042:Collagen Type I; D008567:Membranes, Artificial; D042461:Vascular Endothelial Growth Factor A; D020932:Nerve Growth Factor