Cell Migration and Polarity on Microfabricated Gradients of Extracellular Matrix Proteins

Abstract

This paper explores the effects of the surface density and concentration profiles of extra cellular matrix proteins on the migration of rat intestinal IEC-6 cells. Microfluidic devices were used to create linear, immobilized gradients of laminin. This study investigated both the impact of the steepness and local concentrations on the directedness of cell migration. The bulk concentrations of proteins in the feed streams in the mixing device determined the gradient profile and the local concentration of laminin in the device. Two sets of gradients were used to explore cell migration directedness: (i) gradients with similar change in local concentration, i.e., the same gradient steepness, and (ii) different gradients with similar local concentrations. Cells migrated up the gradients, independent of the steepness of the gradients used in this study. At the same local laminin concentration, the migration rate was independent of the gradient steepness. However, cell directedness decreased significantly at high laminin densities.

Surface Presentation of Bioactive Ligands in a Nonadhesive Background Using DOPA-Tethered Biotinylated Poly(ethylene glycol)

“…1A). Streptavidin binding to surfaces coated with DPB10 was 40-fold greater than for DPB0, and biotin (5)(6)(7)(8) -IgG 1 specifically adsorbed to unfilled streptavidin binding pockets. Binding of streptavidin and biotin (5)(6)(7)(8) -IgG 1 to DPB10 surfaces was evaluated using ellipsometry.…”

“…A. Woodlam, Inc.). The reported thickness, before and after the adsorption of streptavidin and biotinylated IgG 1 (5-8 biotin molecules per IgG 1 ; biotin (5)(6)(7)(8) -IgG 1 ; BD Biosciences, San Jose, CA), was the average from 3 surfaces with 3 different spots measured on each surface. XPS spectra were collected on an Omicron ESCALAB (Omicron, Taunusstein, Germany) with a monochromatic Al Kα (1486.6 eV) 300-W X-ray source.…”

“…We examined sequential adsorption of streptavidin and biotin (5)(6)(7)(8) -IgG 1 to characterize the binding activity of DPB/DP surfaces. Nonspecific adsorption of streptavidin and biotin (5)(6)(7)(8) IgG 1 was very low for surfaces coated with 100% DP (DPB0) (Fig.…”

“…Nonspecific adsorption of streptavidin and biotin (5)(6)(7)(8) IgG 1 was very low for surfaces coated with 100% DP (DPB0) (Fig. 1A).…”

“…Binding of streptavidin and biotin (5)(6)(7)(8) -IgG 1 to DPB10 surfaces was evaluated using ellipsometry. The thickness of the DPB10 layer was 22 ± 2 Å. Sequential adsorption of streptavidin and biotin (5)(6)(7)(8) -IgG 1 increased the thickness by a total of 18 ± 1 Å. The binding of streptavidin and biotin (5)(6)(7)(8) -IgG 1 to DPB10 was confirmed using X-ray photoelectron spectroscopy (XPS; Fig.…”