Formation of perfused, functional microvascular tubes in vitro

Area of Science:

• Biomedical Engineering
• Cell Biology
• Vascular Biology

Background:

• In vitro models are crucial for studying complex biological processes like inflammation.
• Existing models often lack the structural and functional complexity of native microvasculature.
• Developing perfusable 3D vascular constructs is essential for accurate disease modeling.

Purpose of the Study:

• To create and characterize three-dimensional (3D) microvascular tubes in vitro.
• To assess the barrier function, leukocyte interactions, and inflammatory responses of these tubes.
• To establish a perfusable in vitro model for studying inflammation.

Main Methods:

• Formation of confluent monolayers of human endothelial cells within collagen gel channels.
• Perfusion and maturation of the 3D microvascular tubes over time.
• Assessment of tube diameter, barrier integrity, leukocyte adhesion, and inflammatory responses.

Main Results:

• Successfully formed 3D microvascular tubes (5-7 mm length) with initial diameters of 55-120 microm, maturing to 75-150 microm.
• Demonstrated strong endothelial barrier function over 5 days.
• Observed resistance to leukocyte adhesion under basal conditions, with rapid barrier breakdown and leukocyte adhesion upon inflammatory stimulation.
• The tubes exhibited cellular organization and functions similar to in vivo venules and capillaries.

Conclusions:

• The developed 3D microvascular tubes serve as a robust in vitro model for studying vascular inflammation.
• These perfusable constructs accurately mimic key aspects of microvascular physiology and inflammatory responses.
• This model holds significant potential for preclinical research and drug discovery in inflammatory diseases.