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Pumpless Microfluidic Devices for Generating Healthy and Diseased Endothelia



Yang Yang, Parinaz Fathi, Glenn E. Holland, Dipanjan Pan, Nam Wang, Mandy B. Esch


We have developed a pumpless cell culture platform that can recirculate small amounts of cell culture medium (400 µL) in a unidirectional or bidirectional flow pattern. The device produces an average wall shear stress of up to 0.587 Pa ± 0.006 Pa without the use of a pump. It can be used to culture cells that are sensitive to the direction of flow-induced mechanical shear such as human umbilical vein endothelial cells (HUVECs). Using the device we demonstrate that HUVECs produce indicators of endothelial activation (interleukin 6, interleukin 8) under both flwo conditions, but that the secretion was significantly higher under bidirectional flow. Our results show that pumpless devices can be used to simulate the endothelium under healthy and activated conditions depending on the flow pattern chosen. The demonstrated devices can be integrated with pumpless tissues-on-a-chips, allowing for the addition of barrier tissues such as endothelial linings to the tissues grown within.
Lab on A Chip
Created September 27, 2019, Updated October 1, 2019