Rapid perfusion and network remodeling in a microvascular construct after implantation.
OBJECTIVE
We have previously demonstrated the ability to construct 3-dimensional microvascular beds in vitro via angiogenesis from isolated, intact, microvessel fragments that retain endothelial cells and perivascular cells. Our objective was to develop and characterize an experimental model of tissue vascularization, based on the implantation of this microvascular construct, which recapitulated angiogenesis, vessel differentiation, and network maturation.


RESULTS
On implantation in a severe combined-immunodeficient mouse model, vessels in the microvascular constructs rapidly inosculated with the recipient host circulation. Ink perfusion of implants via the left ventricle of the host demonstrated that vessel inosculation begins within the first day after implantation. Evaluation of explanted constructs over the course of 28 days revealed the presence of a mature functional microvascular bed. Using a probe specific for the original microvessel source, 91.7%+/-11% and 88.6%+/-19% of the vessels by day 5 and day 28 after implantation, respectively, were derived from the original microvessel isolate. Similar results were obtained when human-derived microvessels were used to build the microvascular construct.


CONCLUSIONS
With this model, we reproduce the important aspects of vascularization, angiogenesis, inosculation, and network remodeling. Furthermore, we demonstrate that the model accommodates human-derived vessel fragments, enabling the construction of human-mouse vascular chimeras.
Shepherd
Benjamin R
BR
Biomedical Engineering Program, Vascular Research Group, University of Arizona, Tucson 85724, USA.
Chen
Helen Y S
HY
Smith
Cynthia M
CM
Gruionu
Gabriel
G
Williams
Stuart K
SK
Hoying
James B
JB
D000818:Animals; D001808:Blood Vessels / Q000637:transplantation*; D002244:Carbon; D003094:Collagen; D004396:Coloring Agents; D004822:Epididymis; D005260:Female; D005782:Gels; D006801:Humans; D008297:Male; D051379:Mice; D016513:Mice, SCID; D008833:Microcirculation / Q000502:physiology*; D009024:Morphogenesis; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D018919:Neovascularization, Physiologic; D009924:Organ Culture Techniques / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D040521:Subcutaneous Tissue
D004396:Coloring Agents; D005782:Gels; C028433:chinese ink; D002244:Carbon; D003094:Collagen