Dynamic Interfaces between Cells and Surfaces: Electroactive Substrates that Sequentially Release and Attach Cells
作者:Woon-Seok Yeo、Muhammad N. Yousaf、Milan Mrksich
DOI:10.1021/ja038265b
日期:2003.12.1
An electroactivesubstrate that combines dual dynamic properties is demonstrated. A monolayer is patterned to first release an immobilizedligand, and therefore adherent cells, on application of an electrical potential. Subsequently, electrical oxidation of the substrate results in immobilization of ligands, and migration of adherent cells.
A substrate comprises a surface, and a plurality of moieties, on at least a portion of the surface. The moieties are moieties of formula:
Surf-L-Q-T,
where -T comprises a reactant ligand, and Surf- designates where the moiety attaches to the surface. The substrate can be made into a protein chip by the reaction of a reactant ligand and a fusion polypeptide, where the fusion polypeptide includes a capture polypeptide moiety which corresponds to the reactant ligand.
The present invention provides a method, comprising (a) providing a reactant ligand attached to a substrate; (b) contacting the substrate with a fusion polypeptide, said fusion polypeptide comprising a capture polypeptide fused to a display polypeptide under conditions such that said reactant ligand covalently binds to said capture polypeptide; and (c) analyzing said display polypeptide.
In Situ Modulation of Cell Behavior via Smart Dual-Ligand Surfaces
作者:Abigail Pulsipher、Sungjin Park、Debjit Dutta、Wei Luo、Muhammad N. Yousaf
DOI:10.1021/la503521x
日期:2014.11.18
Due to the highly complex nature of the extracellular matrix (ECM), the design and implementation of dynamic, stimuli-responsive surfaces that present well-defined ligands and serve as model ECM substrates have been of tremendous interest to biomaterials, biosensor, and cell biology communities. Such tools provide strategies for identifying specific ligand-receptor interactions that induce vital biological consequences. Herein, we report a novel dual-ligand-presenting surface methodology that modulates dynamic ECM properties to investigate various cell behaviors. Peptides PHSRN, cRGD, and KKKTTK, which mimic the cell- and heparan sulfate-binding domains of fibronectin, and carbohydrates Gal and Man were combined with cell adhesive RGD to survey possible synergistic or antagonist ligand effects on cell adhesion, spreading, growth, and migration. Soluble molecule and enzymatic inhibition assays were also performed, and the levels of focal adhesion kinase in cells subjected to different ligand combinations were quantified. A redox-responsive trigger was incorporated into this surface strategy to spontaneously release ligands in the presence of adhered cells, and cell spreading, growth, and migration responses were measured and compared. The identity and nature of the dual-ligand combination directly influenced cell behavior.