title: Hybrid photopatterned enzymatic reaction (HyPER) for in situ cell manipulation.
abstract: The ability to design artificial extracellular matrices as cell-instructive scaffolds has opened the door to technologies capable of studying the fate of cells in vitro and to guiding tissue repair in vivo. One main component of the design of artificial extracellular matrices is the incorporation of biochemical cues to guide cell phenotype and multicellular organization. The extracellular matrix (ECM) is composed of a heterogeneous mixture of proteins that present a variety of spatially discrete signals to residing cell populations. In contrast, most engineered ECMs do not mimic this heterogeneity. In recent years, photo-deprotection has been used to spatially immobilize signals. However, this approach has been limited mostly to small peptides. Here we combine photo-deprotection with enzymatic reaction to achieve spatially controlled immobilization of active bioactive signals that range from small molecules to large proteins. A peptide substrate for transglutaminase factor XIII (FXIIIa) was caged with a photo-deprotectable group, which was then immobilized to the bulk of a cell-compatible hydrogel. With focused light, the substrate can be deprotected and used to immobilize patterned bioactive signals. This approach offers an innovative strategy to immobilize delicate bioactive signals, such as growth factors, without loss of activity and enables in situ cell manipulation of encapsulated cells.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, CA 90095 (USA).
authors.forename: Donald R
authors.initials: DR
authors.lastname: Griffin
authors.forename: Jacob
authors.initials: J
authors.lastname: Borrajo
authors.forename: Allyson
authors.initials: A
authors.lastname: Soon
authors.forename: Giovanny F
authors.initials: GF
authors.lastname: Acosta-Vélez
authors.forename: Victor
authors.initials: V
authors.lastname: Oshita
authors.forename: Nicole
authors.initials: N
authors.lastname: Darling
authors.forename: Julia
authors.initials: J
authors.lastname: Mack
authors.forename: Thomas
authors.initials: T
authors.lastname: Barker
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Iruela-Arispe
authors.forename: Tatiana
authors.initials: T
authors.lastname: Segura
mesh_terms: D000595:Amino Acid Sequence; D055162:Biocatalysis; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism; D026122:Factor XIIIa / Q000737:chemistry* / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D008027:Light; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D020100:Hydrogels; D009842:Oligopeptides; D026122:Factor XIIIa
keywords: enzyme catalysis; factor XIIIa; hydrogels; nitrobenzene; photochemistry