3D PRINTING AND PATTERNING VASCULATURE IN ENGINEERED TISSUES - 3D Bioprinting and Nanotechnology in Tissue Engineering and Regenerative Medicine - page 176

FIGURE 8.3
Demonstrating vasculogenic and angiogenic vessel formation in different systems. (A) Microfluidic vessel
network formed by injection molding techniques, which was then stacked and sealed to result in an enclosed
fluidic structure: (i) overall network structure, (ii) angiogenesis formation of sprouting endothelial cells, (iii)
endothelial sprouting with perivascular interaction. Scale bars = 100 m m; figure adapted from Zheng et al. (2012) .
(B) Endothelial cells shown to sprout over time (early sprouts: (i and ii); late sprouts: (iii)), forming into matured
neovessels that are lumenized end-to-end (iv). Scale bars = 25 m m; figure adapted from Nguyen et al. (2013) . (C)
Microfluidic device fabricated from soft lithography and replica molding: (i) cells encapsulated inside a channel
demonstrate microvascular networks formed through vasculogenesis after 2 days in culture, (ii) cells coated inside a
channel demonstrate angiogenic sprouts after 2 days in culture. Scale bars = 20 m m; figure adapted from Kim et al .
(2013) . (D) Cords constructed from a microtissue molding approach demonstrating formation of new capillaries
along the length of the patterned cords after 7 days of implantation (arrows point to sprouts, arrowheads point to
cords). Scale bar = 25 m m; figure adapted from Baranski et al. (2013) . (E) Histological analysis of bioprinted cells
onto skin wounds of a mice indicating thicker regeneration of tissue with more blood vessels in mesenchymal stem
cell and amniotic fluid-derived stem cell treated patches compared to gel only (arrows point to vessels formed
in vivo ). Scale bars = 50 m m; figure adapted from Skardal et al. (2012) . (F) Perfusable 3D engineered tissues
fabricated from casting of patterned networks: (i) Endothelial lining of microchannel surrounded by 10T1/2 cells
after 9 days in culture, (ii and iii) endothelial sprouts from patterned vasculature at different positions along the
same vessel network (arrowheads point to sprouts). Scale bars = 200 m m; figure adapted from Miller et al. (2012) .
8.1.6 ANGIOGENESIS, VASCULOGENESIS, AND IN VIVO INTEGRATION
Over the past few years, significant progress has been made to achieve perfusable microchannels
containing cells; however, for translational applications, angiogenesis, vasculogenesis, and in vivo