Acceleration of vascular sprouting from fabricated perfusable vascular-like structures

PLoS One. 2015 Apr 10;10(4):e0123735. doi: 10.1371/journal.pone.0123735. eCollection 2015.

Abstract

Fabrication of vascular networks is essential for engineering three-dimensional thick tissues and organs in the emerging fields of tissue engineering and regenerative medicine. In this study, we describe the fabrication of perfusable vascular-like structures by transferring endothelial cells using an electrochemical reaction as well as acceleration of subsequent endothelial sprouting by two stimuli: phorbol 12-myristate 13-acetate (PMA) and fluidic shear stress. The electrochemical transfer of cells was achieved using an oligopeptide that formed a dense molecular layer on a gold surface and was then electrochemically desorbed from the surface. Human umbilical vein endothelial cells (HUVECs), adhered to gold-coated needles (ϕ600 μm) via the oligopeptide, were transferred to collagen gel along with electrochemical desorption of the molecular layer, resulting in the formation of endothelial cell-lined vascular-like structures. In the following culture, the endothelial cells migrated into the collagen gel and formed branched luminal structures. However, this branching process was strikingly slow (>14 d) and the cell layers on the internal surfaces became disrupted in some regions. To address these issues, we examined the effects of the protein kinase C (PKC) activator, PMA, and shear stress generated by medium flow. Addition of PMA at an optimum concentration significantly accelerated migration, vascular network formation, and its stabilization. Exposure to shear stress reoriented the cells in the direction of the medium flow and further accelerated vascular network formation. Because of the synergistic effects, HUVECs began to sprout as early as 3 d of perfusion culture and neighboring vascular-like structures were bridged within 5 d. Although further investigations of vascular functions need to be performed, this approach may be an effective strategy for rapid fabrication of perfusable microvascular networks when engineering three-dimensional fully vascularized tissues and organs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Vessels / cytology
  • Blood Vessels / growth & development*
  • Blood Vessels / physiology*
  • Cell Adhesion
  • Collagen
  • Electrochemical Techniques
  • Enzyme Activation / drug effects
  • Gold
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Hydrodynamics
  • Microvessels / cytology
  • Microvessels / growth & development
  • Microvessels / physiology
  • Neovascularization, Physiologic
  • Oligopeptides
  • Protein Kinase C / metabolism
  • Regenerative Medicine
  • Surface Properties
  • Tetradecanoylphorbol Acetate / pharmacology
  • Tissue Engineering / methods*

Substances

  • Oligopeptides
  • Gold
  • Collagen
  • Protein Kinase C
  • Tetradecanoylphorbol Acetate

Grants and funding

This work was supported by the Ministry of Education, Culture, Sports, Science, and Technology of Japan, 25289291, 26630423, 26106712 (http://www.mext.go.jp/english/) to (JF) and New Energy and Industrial Technology Development Organization, 11B09003d (http://www.nedo.go.jp/english/index.html) to (JF) and ALCA, Japan Science and Technology Agency (http://www.jst.go.jp/EN/index.html) to (JF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.