As bioprinting advances into clinical relevance with patient-specific tissue and organ constructs, it must be capable of multi-material fabrication at high resolutions to accurately mimick the complex tissue structures found in the body. One of the most fundamental structures to regenerative medicine is microvasculature. Its continuous hierarchical branching vessel networks bridge surgically manipulatable arteries (∼1–6 mm) to capillary beds (∼10
Macrophages may play a beneficial role in blood vessel development. To study the role of macrophages in vessel development for regenerative medicine, a bioactive poly(ethylene glycol)‐based hydrogel scaffold that is modified for integrin‐mediated cell adhesion and biodegradation by matrix‐metalloproteinases 2 and 9 is utilized. This scaffold serves as a tunable cell microenvironment and supports the formation of microvascular networks. When encapsulated with endothelial cells, macrophages enhance vessel tubule volume within the hydrogel by nearly twofold compared to endothelial cells alone in hydrogels. Additionally, macrophages in the hydrogel alter their morphology in an endothelial cell‐dependent manner. Macrophages alone maintain high circularity with only 1% of the population demonstrating circularity ≤0.5 (indicating cell spreading), but when co‐encapsulated with endothelial cells, 46% of macrophages have a circularity ≤0.5. Macrophages 0–5 µm away from an endothelial cell have a circularity of 0.48 ± 0.22 whereas macrophages >20 µm away have a circularity of 0.83 ± 0.07. Two types of macrophage–endothelial cell interactions are seen: macrophages behaving as pericyte‐like cells and macrophages bridging between endothelial cells. Macrophages may be a novel cell target for regenerative medicine efforts where vasculature is often vital to success.
more » « less- NSF-PAR ID:
- 10034008
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Biosystems
- Volume:
- 1
- Issue:
- 3
- ISSN:
- 2366-7478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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