title: Spatially controlled simultaneous patterning of multiple growth factors in three-dimensional hydrogels.
abstract: Three-dimensional (3D) protein-patterned scaffolds provide a more biomimetic environment for cell culture than traditional two-dimensional surfaces, but simultaneous 3D protein patterning has proved difficult. We developed a method to spatially control the immobilization of different growth factors in distinct volumes in 3D hydrogels, and to specifically guide differentiation of stem/progenitor cells therein. Stem-cell differentiation factors sonic hedgehog (SHH) and ciliary neurotrophic factor (CNTF) were simultaneously immobilized using orthogonal physical binding pairs, barnase-barstar and streptavidin-biotin, respectively. Barnase and streptavidin were sequentially immobilized using two-photon chemistry for subsequent concurrent complexation with fusion proteins barstar-SHH and biotin-CNTF, resulting in bioactive 3D patterned hydrogels. The technique should be broadly applicable to the patterning of a wide range of proteins.
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George Street, Toronto, Ontario M5S 3H6, Canada.
authors.forename: Ryan G
authors.initials: RG
authors.lastname: Wylie
authors.forename: Shoeb
authors.initials: S
authors.lastname: Ahsan
authors.forename: Yukie
authors.initials: Y
authors.lastname: Aizawa
authors.forename: Karen L
authors.initials: KL
authors.lastname: Maxwell
authors.forename: Cindi M
authors.initials: CM
authors.lastname: Morshead
authors.forename: Molly S
authors.initials: MS
authors.lastname: Shoichet
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry; D040761:Biomimetic Materials / Q000737:chemistry*; D001710:Biotin / Q000737:chemistry; D018929:Cell Culture Techniques; D020934:Ciliary Neurotrophic Factor / Q000737:chemistry; D053823:Hedgehog Proteins / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis*; D036341:Intercellular Signaling Peptides and Proteins / Q000737:chemistry*; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D012260:Ribonucleases / Q000737:chemistry; D012685:Sepharose / Q000737:chemistry; D019809:Streptavidin / Q000737:chemistry; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D020934:Ciliary Neurotrophic Factor; D053823:Hedgehog Proteins; D020100:Hydrogels; D036341:Intercellular Signaling Peptides and Proteins; D011993:Recombinant Fusion Proteins; C057438:barstar protein, Bacillus amyloliquefaciens; D001710:Biotin; D012685:Sepharose; D019809:Streptavidin; D012260:Ribonucleases; C019760:Bacillus amyloliquefaciens ribonuclease