A Microfluidic Device to Compare Shear Flow Vs Chemokine Signaling Effects on Immune Cell Migration

Microfluidics systems are widely used in various scientific fields for the analysis of components in micro/nano volumes of fluid. Analysis of concurrent signal influencing T-cell migration is best observed in vivo, but an effective in vitro model would be more beneficial for research applications. Specifically, studying cellular migration is important in order to better understand how chronic conditions occur, and to better evaluate treatments for these conditions. Neutrophils and T-cells can be co-cultured with endothelial human umbilical vein endothelial cells (HUVEC) or endothelial ligands to mimic immune cell migration on the vascular endothelial surface. There are systems on the market that allow for examination of cell migration for individual signals such as shear flow or chemokine gradient; however, there are no systems that allow for simultaneous examination of the effects of both cellular signals on cell migration. We aim to create a multiple-inlet microfluidic device to analyze the migration of T-cells in response to the chemokine gradient and shear stress flow. Our proposed design was created for a specific customer need: the ability to simultaneously view the effects of shear and chemokine flows. Polymethyl methacrylate (PMMA) will be used to build the microfluidic device. Endothelial cells will be seeded on a microscope slide that will be placed in the device, with T-cells seeded on top. A thermoplastic elastomer (TPE) strip will be used as a gasket on the microscope slide as a channel for the individual flows to follow. A peristaltic pump will be utilized to control flow rates of the shear flow and the chemokine flow. A prototype has been developed based on our design, and further modification to best suit clinical and research purposes is underway. Furthermore, we plan to conduct experiments that can determine which cellular migration signal will have a greater influence on T-cells using the microfluidics prototype. Based on the preference of the T-cells towards the chemokine gradient or the shear flow, the T-cells will migrate in the direction of specific outlets in our device, which will allow us to determine the cellular response to these signals. Through determining which cellular migration signal affects T-cells, we can understand the pathophysiology of chronic conditions and better target these biological mechanisms. We aim to have distinct detection of T-cells migration for creation of specific therapeutic interventions that can improve individuals’ quality of living.