Cross-Linking Chemistry of Tyramine-Modified Hyaluronan Hydrogels Alters Mesenchymal Stem Cell Early Attachment and Behavior

Biomacromolecules. 2017 Mar 13;18(3):855-864. doi: 10.1021/acs.biomac.6b01740. Epub 2017 Feb 10.

Abstract

Given the significance of hydrogels as cell-instructive materials, it is important to understand how differences in their chemical and physical properties are able to direct cell fate. For example, it remains unclear how different hydrogel cross-linking chemistries and gelation mechanisms influence cell behavior. Here, we report on hyaluronan-tyramine (HA-Tyr) hydrogels prepared either with enzymatic cross-linking using horseradish peroxidase and H2O2 or with visible light (500 nm) triggered gelation. We demonstrate that when hydrogels are polymerized to equivalent Young's moduli, the specific cross-linking chemistry of HA-Tyr hydrogels can have a substantial impact on mesenchymal stem cell (MSC) behavior. MSCs cultured on HA-Tyr hydrogels exhibit increased cell spread areas on enzymatically formed substrates relative to photo-cross-linked matrices. While enzymatically formed hydrogels led to MSCs exhibiting greater cell focal adhesion length, MSCs cultured on the photo-cross-linked matrices exhibited smaller cell spread area and shorter focal adhesion length but generated increased traction stress. These findings highlight the importance of understanding hydrogel cross-linking chemistries when the role of biophysical cues in regulating stem cell fate is investigated.

MeSH terms

  • Animals
  • Biocompatible Materials / chemistry
  • Cattle
  • Cell Adhesion / drug effects
  • Cell Differentiation / drug effects
  • Cells, Cultured
  • Elastic Modulus / drug effects
  • Horseradish Peroxidase / metabolism
  • Hyaluronic Acid / chemistry*
  • Hydrogels / chemistry*
  • Hydrogen Peroxide / metabolism
  • Mechanical Phenomena
  • Mesenchymal Stem Cells / drug effects*
  • Tyramine / chemistry*

Substances

  • Biocompatible Materials
  • Hydrogels
  • Hyaluronic Acid
  • Hydrogen Peroxide
  • Horseradish Peroxidase
  • Tyramine