Skip to main content
eScholarship
Open Access Publications from the University of California

UC San Diego

UC San Diego Electronic Theses and Dissertations bannerUC San Diego

Dynamic surface topography influences cell function

Abstract

Micro- and nano-scale changes in surface topography can modulate mesenchymal stem cell (MSC) differentiation; rough surfaces have been shown to induce osteogenesis to varying degrees depending on the scale and nature of the topographical features. However, in the in vivo environment, topography is constantly changing due to remodeling by cells within the niche. To better understand how mesenchymal stem cells respond to changes in topography over time, we developed a soft polyacrylamide hydrogel with magnetic nickel microwires randomly oriented in the surface of the material. Varying the magnetic field around the microwires can reversibly induce their alignment with the direction of the field, causing the smooth hydrogel surface to develop small wrinkles. By varying the density of wires in the hydrogel, surface roughness changes, R_RMS, ranged from 0.09 um (wire-free substrates) to 0.52 (maximum wire density) a custom displacement mapping software. Time-dependent topographical changes were achieved by oscillating the field around the microwires using step function or cyclic changes. Smooth muscle cells plated onto these substrates changed morphology by shrinking within minutes of inducing a step change in topography. However, on a longer time scale characterized by a continual modulation of topography, cells show no appreciable response, likely due to their propensity to remodel over longer time scales. Being able to dynamically study how cells respond to changes in topography will improve our current understanding of topography-driven effects on cell behavior, and eventually, on stem cell differentiation

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View