Enhancing mechanical properties of tissue-engineered constructs via lysyl oxidase crosslinking activity.

Journal Article (Journal Article)

A number of strategies have been investigated to enhance the mechanical stability of engineered tissues. In this study, we utilized lysyl oxidase (LO) to enzymatically crosslink extracellular matrix (ECM) proteins, particularly collagen and elastin, to enhance the mechanical integrity of the ECM and thereby impart mechanical strength to the engineered tissue. Vascular smooth muscle cells (VSMCs) were liposomally transfected with the LO gene. Both Northern and Western analyses confirmed increased LO expression. Increased LO activity was demonstrated using a fluorescent enzyme substrate assay and by observation of the presence of increased levels of desmosine, a product of LO crosslinking, in the ECM. The mechanical effects of altered crosslink densities within tissue-engineered constructs were demonstrated in a VSMC-populated collagen gel model. When smooth muscle cells transfected with lysyl oxidase were seeded in collagen gels, the tensile strength and elastic modulus in these constructs increased by approximately two-fold compared to constructs seeded with mock-transfected VSMCs. Also, desmosine levels in the LO-populated collagen gels were higher than they were in mock-seeded gels, as demonstrated via immunohistochemical staining. Compositional analysis of the ECM deposited by the transformed cells showed similar collagen and elastin levels, and cell proliferation rates were similar as well, thus attributing increased mechanical properties to ECM crosslinking.

Full Text

Duke Authors

Cited Authors

  • Elbjeirami, WM; Yonter, EO; Starcher, BC; West, JL

Published Date

  • September 2003

Published In

Volume / Issue

  • 66 / 3

Start / End Page

  • 513 - 521

PubMed ID

  • 12918034

Electronic International Standard Serial Number (EISSN)

  • 1552-4965

International Standard Serial Number (ISSN)

  • 1549-3296

Digital Object Identifier (DOI)

  • 10.1002/jbm.a.10021


  • eng