In vitro angiogenesis assay for the study of cell-encapsulation therapyElectronic supplementary information (ESI) available. See DOI: 10.1039/c2lc40182g

• Main Authors: Kim, Choong, Chung, Seok, Yuchun, Liu, Kim, Min-Cheol, Chan, Jerry K. Y, Asada, H. Harry, Kamm, Roger D
• Format: Journal Article
• Language: English
• Published: 17.07.2012
• ISSN: 1473-0197; 1473-0189
• DOI: 10.1039/c2lc40182g

Cell encapsulation within alginate beads has potential as a sustained release system for delivering therapeutic agents in vivo while protecting encapsulated cells from the immune system. There is, however, no in vitro model for cell-encapsulation therapy that provides a suitable platform for quantitative assessment of physiological responses to secreted factors. Here we introduce a new microfluidic system specifically designed to evaluate and quantify the pro -angiogenic potential of factors secreted from human fetal lung fibroblasts encapsulated in beads on an intact endothelial cell monolayer. We confirmed that cell-encapsulating beads induced an angiogenic response in vitro , demonstrated by a strong correlation between the encapsulated cell density in the beads and the length of the vascular lumen formed in vitro . Conditions established by in vitro tests were then further shown to exert a pro -angiogenic response in vivo using a subcutaneous mouse model, forming an extensive network of functional luminal structures perfused with red blood cells. We introduce a new assay for evaluating and quantifying capillary growth from an intact endothelial cell monolayer in response to factors released from human fetal lung fibroblasts encapsulated in beads.