Multiscale Imaging to Monitor Functional SHED-Supported Engineered Vessels

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Vascular Biology

Background:

• Orofacial tissue regeneration is limited by poor vascular supply.
• Prevascularized engineered constructs offer a solution for rapid graft vascularization.
• Dental pulp stem cells possess angiogenic properties beneficial for tissue engineering.

Purpose of the Study:

• To establish a preclinical model of prevascularized constructs using stem cells from human exfoliating deciduous teeth (SHED).
• To functionally analyze in vivo angiogenesis, vascular perfusion, and permeability of these constructs.
• To evaluate the potential of SHED in promoting functional vascular networks for orofacial tissue engineering.

Main Methods:

• Three cell-loaded hydrogel constructs (SHED-HUVEC, HUVEC with SHED-conditioned medium, SHED alone) were fabricated in polylactic acid (PLA) grids.
• Constructs were ectopically implanted in athymic mice.
• In vivo PETscan, ex vivo micro-CT, 2-photon microscopy with lectin/dextran injection were used for analysis.

Main Results:

• The SHED-HUVEC group showed significantly increased radiotracer uptake (angiogenesis) on PETscan at day 10.
• Micro-CT confirmed greater vascular volume in SHED-HUVEC constructs at day 30.
• SHED-HUVEC constructs exhibited enhanced blood perfusion and reduced vascular leakage, indicating functional vessel maturation.

Conclusions:

• Novel PLA-based prevascularized constructs loaded with SHED and HUVECs promote functional human-engineered vessels.
• SHED actively contribute to the maturation and stability of engineered microvascular networks.
• PETscan is validated as a tool for early detection of in vivo angiogenesis in tissue engineering grafts.