Investigating the Impact of Shear Stress on Lymphatic Endothelial Cells Using a Microfluidic Model
The lymphatic system, consisting of lymph vessels, ducts, nodes and tissues organized throughout the body, serves to regulate fluid homeostasis, defend against disease, and aid in the absorption of nutrients. To maintain a healthy environment, lymphatic endothelial cells continuously adapt and respond to mechanical changes arising from disease and immune response. Through this investigation, Human Dermal Lymphatic Endothelial Cells (HDLECs) were tested against shear stress from flowing media to test maintenance of their lymphatic phenotype. It is hypothesized that HDLECs will be able to maintain their lymphatic phenotype under increased shear stress due to the shear stress in lymphatics in vivo. A single channel microfluidic device was developed in order to investigate this hypothesis. HDLECs were cultured and stained with LYVE-1 antibody, perfused through the devices and allowed to form a confluent monolayer in the device, modeling a lumen. Additional resistance channels were added to vary the shear stress on the cells, ranging from physiologic shear stresses in lymphatics (0.5 dyne/cm2) to shear stresses in veins (20 dyne/cm2) and devices were imaged over time to demonstrate changes in LYVE-1 expression, morphology, and confluency. Cells in devices were compared to cells in a well plate, resembling static (no shear stress) conditions. The results of this study will aid in future microfluidic investigations in immunotherapies by providing insight into lymphocytes’ responses to physiologic mechanical stresses.