These authors contributed equally to this work.
Crosslinking of collagen scaffolds promotes blood and lymphatic vascular stability
Article first published online: 22 OCT 2013
© 2013 Wiley Periodicals, Inc.
Journal of Biomedical Materials Research Part A
Volume 102, Issue 9, pages 3186–3195, September 2014
How to Cite
How to cite this article: 2014. Crosslinking of collagen scaffolds promotes blood and lymphatic vascular stability. J Biomed Mater Res Part A 2014: 102A: 3186–3195., , , , , , .
- Issue published online: 24 JUL 2014
- Article first published online: 22 OCT 2013
- Manuscript Accepted: 2 OCT 2013
- Manuscript Revised: 11 SEP 2013
- Manuscript Received: 23 JUL 2013
- National Heart, Lung, and Blood Institute. Grant Number: HL092335
- Boston University Undergraduate Research Opportunities Program
- microvascular tissue engineering;
- vascular physiology;
- extracellular matrix;
The low stiffness of reconstituted collagen hydrogels has limited their use as scaffolds for engineering implantable tissues. Although chemical crosslinking has been used to stiffen collagen and protect it against enzymatic degradation in vivo, it remains unclear how crosslinking alters the vascularization of collagen hydrogels. In this study, we examine how the crosslinking agents genipin and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide alter vascular stability and function in microfluidic type I collagen gels in vitro. Under moderate perfusion (∼10 dyn/cm2 shear stress), tubes of blood endothelial cells (ECs) exhibited indistinguishable stability and barrier function in untreated and crosslinked scaffolds. Surprisingly, under low perfusion (∼5 dyn/cm2 shear stress) or nearly zero transmural pressure, microvessels in crosslinked scaffolds remained stable, while those in untreated gels rapidly delaminated and became poorly perfused. Similarly, tubes of lymphatic ECs under intermittent flow were more stable in crosslinked gels than in untreated ones. These effects correlated well with the degree of mechanical stiffening, as predicted by analysis of fracture energies at the cell–scaffold interface. This work demonstrates that crosslinking of collagen scaffolds does not hinder normal EC physiology; instead, crosslinked scaffolds promote vascular stability. Thus, routine crosslinking of scaffolds may assist in vascularization of engineered tissues. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3186–3195, 2014.