title: Composite System of Graphene Oxide and Polypeptide Thermogel As an Injectable 3D Scaffold for Adipogenic Differentiation of Tonsil-Derived Mesenchymal Stem Cells.
abstract: As two-dimensional (2D) nanomaterials, graphene (G) and graphene oxide (GO) have evolved into new platforms for biomedical research as biosensors, imaging agents, and drug delivery carriers. In particular, the unique surface properties of GO can be an important tool in modulating cellular behavior and various biological sequences. Here, we report that a composite system of graphene oxide/polypeptide thermogel (GO/P), prepared by temperature-sensitive sol-to-gel transition of a GO-suspended poly(ethylene glycol)-poly(L-alanine) (PEG-PA) aqueous solution significantly enhances the expression of adipogenic biomarkers, including PPAR-γ, CEBP-α, LPL, AP2, ELOVL3, and HSL, compared to both a pure hydrogel system and a composite system of G/P, graphene-incorporated hydrogel. We prove that insulin, an adipogenic differentiation factor, preferentially adhered to GO, is supplied to the incorporated stem cells in a sustained manner over the three-dimensional (3D) cell culture period. On the other hand, insulin is partially denatured in the presence of G and interferes with the adipogenic differentiation of the stem cells. The study suggests that a 2D/3D composite system is a promising platform as a 3D cell culture matrix, where the surface properties of 2D materials in modulating the fates of the stem cells are effectively transcribed in a 3D culture system.
authors: Department of Chemistry and Nanoscience, Ewha Womans University , 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, Korea.
authors: Madhumita
authors: M
authors: Patel
authors: Department of Chemistry and Nanoscience, Ewha Womans University , 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, Korea.
authors: Hyo Jung
authors: HJ
authors: Moon
authors: Department of Chemistry and Nanoscience, Ewha Womans University , 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, Korea.
authors: Du Young
authors: du Y
authors: Ko
authors: Department of Chemistry and Nanoscience, Ewha Womans University , 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, Korea.
authors: Byeongmoon
authors: B
authors: Jeong
mesh_terms: D050156:Adipogenesis / Q000187:drug effects*; D000409:Alanine / Q000737:chemistry; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects*; D004337:Drug Carriers / Q000737:chemistry; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D006108:Graphite / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000187:drug effects*; D010087:Oxides / Q000737:chemistry; D014066:Palatine Tonsil / Q000166:cytology; D010455:Peptides / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D023822:Tissue Engineering
chemical_list: D004337:Drug Carriers; D010087:Oxides; D010455:Peptides; D011092:Polyethylene Glycols; D006108:Graphite; D000409:Alanine
keywords: 3D culture; graphene oxide; hybrid system; sol−gel transition; stem cell