Annals of Biomedical Engineering

, Volume 43, Issue 7, pp 1531–1542 | Cite as

In Silico Investigation of Angiogenesis with Growth and Stress Generation Coupled to Local Extracellular Matrix Density

  • Lowell T. Edgar
  • James B. Hoying
  • Jeffrey A. WeissEmail author


Mechanical interactions during angiogenesis, i.e., traction applied by neovessels to the extracellular matrix and the corresponding deformation, are important regulators of growth and neovascularization. We have previously designed, implemented, and validated a coupled model of angiogenesis in which a discrete microvessel growth model interacts with a continuous finite element mesh through the application of local remodeling sprout stresses (Edgar et al. in Biomech Model Mechanobiol, 2014). However, the initial implementation of this framework does not take matrix density into account when determined these remodeling stresses and is therefore insufficient for the study of angiogenesis within heterogeneous matrix environments such as those found in vivo. The objective of this study was to implement sensitivity to matrix density in the active stress generation within AngioFE in order to allow the study of angiogenic growth within a heterogeneous density environment. We accomplished this by scaling active sprout stresses relative to local matrix density using a scaling factor previously determined from experimental data. We then exercised the new functionality of the model by simulating angiogenesis within four different scenarios: homogeneous density, a narrow gap model, and matrix density gradient, and a construct subjected to repeated loading/unloading and preconditioning. These numerical experiments predicted heterogeneous matrix density in the initially homogeneous case, the closure and alignment of microvessels along a low-density gap, the formation of a unique cap-like structure during angiogenesis within a density gradient, and the alignment of microvessels in the absence of applied load due to preconditioning. The result of these in silico investigations demonstrate how matrix heterogeneity affects neovascularization and matrix deformation and provides a platform for studying angiogenesis in complicated and multi-faceted mechanical environments that microvessels experience in vivo.


Angiogenesis Extracellular matrix Cellular mechanics Cell–matrix interactions Finite element modeling Growth modeling 



Financial support from National Institutes of Health #R01HL077683, R01GM083925 and R01EB015133 is gratefully acknowledged.

Conflict of interest

The authors state no conflicting interests.

Supplementary material

Supplementary material 1 (AVI 30066 kb)

Supplementary material 2 (AVI 28269 kb)

Supplementary material 3 (AVI 28526 kb)

Supplementary material 4 (AVI 39882 kb)


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Copyright information

© Biomedical Engineering Society 2015

Authors and Affiliations

  • Lowell T. Edgar
    • 1
  • James B. Hoying
    • 2
  • Jeffrey A. Weiss
    • 1
    Email author
  1. 1.Department of Bioengineering and Scientific Computing and Imaging InstituteUniversity of UtahSalt Lake CityUSA
  2. 2.Division of Cardiovascular Therapeutics, Cardiovascular Innovation InstituteUniversity of LouisvilleLouisvilleUSA

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