Producing Collagen Micro-stripes with Aligned Fibers for Cell Migration Assays

Danahe Mohammed; Gaspard Pardon; Marie Versaevel; Céline Bruyère; Laura Alaimo; Marine Luciano; Eléonore Vercruysse; Beth L Pruitt; Sylvain Gabriele

doi:10.1007/s12195-019-00600-4

Producing Collagen Micro-stripes with Aligned Fibers for Cell Migration Assays

Cell Mol Bioeng. 2019 Sep 25;13(1):87-98. doi: 10.1007/s12195-019-00600-4. eCollection 2020 Feb.

Authors

Danahe Mohammed¹, Gaspard Pardon², Marie Versaevel¹, Céline Bruyère¹, Laura Alaimo¹, Marine Luciano¹, Eléonore Vercruysse¹, Beth L Pruitt^{2

3}, Sylvain Gabriele¹

Affiliations

¹ Laboratory for Complex Fluids and Interfaces, Mechanobiology and Soft Matter Group, Research Institute for Biosciences, University of Mons, Place du Parc, 20, 7000 Mons, Belgium.
² Departments of Bioengineering and Mechanical Engineering, Microsystems Laboratory, Stanford University, 452 Escondido Mail, Stanford, CA 94305-4040 USA.
³ BioMolecular Science and Engineering, and Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA USA.

Abstract

Introduction: The orientation of collagen fibers in native tissues plays an important role in cell signaling and mediates the progression of tumor cells in breast cancer by a contact guidance mechanism. Understanding how migration of epithelial cells is directed by the alignment of collagen fibers requires in vitro assays with standardized orientations of collagen fibers.

Methods: To address this issue, we produced micro-stripes with aligned collagen fibers using an easy-to-use and versatile approach based on the aspiration of a collagen solution within a microchannel. Glass coverslips were functionalized with a (3-aminopropyl)triethoxysilane/glutaraldehyde linkage to covalently anchor micro-stripes of aligned collagen fibers, whereas microchannels were functionalized with a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) nonionic triblock polymer to prevent adhesion of the collagen micro-stripes.

Results: Using this strategy, microchannels can be peeled off to expose micro-stripes of aligned collagen fibers without affecting their mechanical integrity. We used time-lapse confocal reflection microscopy to characterize the polymerization kinetics of collagen networks for different concentrations and the orientation of collagen fibers as a function of the microchannel width. Our results indicate a non-linear concentration dependence of the area of fluorescence, suggesting that the architecture of collagen networks is sensitive to small changes in concentration. We show the possibility to influence the collagen fibril coverage by adjusting the concentration of the collagen solution.

Conclusion: We applied this novel approach to study the migration of epithelial cells, demonstrating that collagen micro-stripes with aligned fibers represent a valuable in-vitro assay for studying cell contact guidance mechanisms.

Keywords: Alignment; Cell migration; Collagen fibers; Contact guidance.