title: Type I collagen-functionalized supported lipid bilayer as a cell culture platform.
abstract: The supported phospholipid bilayer serves as an important biomimetic model for the cell membrane in both basic and applied scientific research. We have constructed a biomimetic platform based on a supported phospholipid bilayer that is functionalized with type I collagen to serve as a substrate for cell culture. To create the type I collagen-functionalized lipid bilayer assembly, a simple chemical approach was employed: lipid vesicles composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(glutaryl) (DP-NGPE), a carboxylic acid-functionalized phospholipid, were prepared and then fused onto an SiO(2) substrate to form a supported lipid bilayer. Subsequently, type I collagen molecules were introduced to form stable collagen-lipid conjugates via amide linkages with activated DP-NGPE lipids. The binding kinetics of the conjugation process and the resultant changes in film thickness and viscoelasticity were followed using the quartz crystal microbalance with dissipation (QCM-D) monitoring. The morphology of the conjugated collagen adlayer was investigated with atomic force microscopy (AFM). We observed that the adsorbed collagen molecules tended to self-assemble into fibrillar structures. Fluorescence recovery after photobleaching (FRAP) was utilized to estimate lateral lipid mobility, which was reduced by up to 20% after the coupling of type I collagen to the underlying lipid bilayer. As a cell culture platform, the collagen-conjugated supported lipid bilayer showed promising results. Smooth muscle cells (A10) retained normal growth behavior on the collagen-functionalized platform, unlike the bare POPC lipid bilayer and the POPC/DG-NGPE bilayer without collagen. The biomimetic functionalized lipid system presented here is a simple, yet effective approach for constructing a cell culture platform to explore the interactions between extracellular matrix components and cells.
authors.affiliation: Genomics Research Center, Academia Sinica, Taipei 115, Taiwan.
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Huang
authors.forename: Nam-Joon
authors.initials: NJ
authors.lastname: Cho
authors.forename: Chih-Jung
authors.initials: CJ
authors.lastname: Hsu
authors.forename: Po-Yuan
authors.initials: PY
authors.lastname: Tseng
authors.forename: Curtis W
authors.initials: CW
authors.lastname: Frank
authors.forename: Ying-Chih
authors.initials: YC
authors.lastname: Chang
mesh_terms: D002460:Cell Line; D024042:Collagen Type I / Q000737:chemistry*; D008051:Lipid Bilayers; D018625:Microscopy, Atomic Force
chemical_list: D024042:Collagen Type I; D008051:Lipid Bilayers