Improvement of vascularization of PLGA scaffolds by inosculation of in situ-preformed functional blood vessels with the host microvasculature.
OBJECTIVE
We analyzed, in vivo, whether the establishment of blood supply to implanted scaffolds can be accelerated by inosculation of an in situ-preformed microvascular network with the host microvasculature.


BACKGROUND
A rapid vascularization is crucial for the survival of scaffold-based transplanted tissue constructs.


METHODS
Poly-lactic-glycolic acid scaffolds were implanted into the flank of balb/c or green fluorescent protein (GFP)-transgenic mice for 20 days to create in situ a new microvascular network within the scaffolds. The prevascularized scaffolds were then transferred into the dorsal skinfold chamber of isogeneic recipient mice. Nonvascularized poly-lactic-glycolic acid scaffolds served as controls. Vascularization, blood perfusion, and cell survival of the implants were analyzed over 14 days using intravital fluorescence microscopy, histology, and immunohistochemistry.


RESULTS
Our results demonstrate that establishment of blood perfusion of prevascularized scaffolds is significantly accelerated and improved (136.7 +/- 23.2 pl/s) when compared with controls (6.9 +/- 1.9 pl/s), because the in situ-preformed microvessels were reperfused by forming interconnections to the host microvasculature. Apoptotic cell death within the implants was found only during the first 3 to 6 days after scaffold implantation during lack of blood perfusion, but not during the further 14-day observation period.


CONCLUSIONS
Inosculation of in situ-preformed functional blood vessels represents a promising approach to improve the blood supply to implanted tissue constructs.
Laschke
Matthias W
MW
Institute for Clinical and Experimental Surgery, University of Saarland, Homburg/Saar, Germany. matthias.laschke@uniklinik-saarland.de
Rücker
Martin
M
Jensen
Gunnar
G
Carvalho
Carlos
C
Mülhaupt
Rolf
R
Gellrich
Nils-Claudius
NC
Menger
Michael D
MD
D000818:Animals; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D019344:Lactic Acid; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008833:Microcirculation; D018919:Neovascularization, Physiologic; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D054457:Tissue Scaffolds / Q000737:chemistry
D049452:Green Fluorescent Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid