Construction of functional tissue-engineered microvasculatures using circulating fibrocytes as mural cells

Area of Science:

• Regenerative Medicine
• Vascular Biology
• Tissue Engineering

Background:

• Mural cells are vital for microvasculature function.
• A significant hurdle in microvascular tissue engineering is sourcing appropriate mural cells.

Purpose of the Study:

• To investigate circulating fibrocytes (CFs) as a potential cellular source for mural cells in microvascular tissue engineering.

Main Methods:

• In vitro assessment of CFs' interaction with vascular endothelial cells (VECs) in collagen gels.
• In vivo transplantation of CFs and VECs into nude mice within collagen gel or Matrigel scaffolds.
• Comparative analysis of CF behavior versus human brain vascular pericytes (HBVPs).

Main Results:

• In vitro, CFs stabilized VEC-formed microvasculatures, formed gap junctions with VECs, and induced basement membrane formation.
• In vivo, transplanted CFs sheathed microvasculatures, induced basement membrane formation, and facilitated host circulation integration.
• CFs exhibited distinct behaviors from HBVPs, including less infiltration, proliferation, endocytosis, and migration.

Conclusions:

• Circulating fibrocytes are a suitable cellular source for mural cells in tissue-engineered microvasculatures.
• CFs possess key functional characteristics required for constructing functional microvascular networks.