(D-138) A Microfluidic Device to Compare Shear Flow vs Chemokine Signaling Effects on Immune Cell Migration

Introduction:: Microfluidics systems are widely used in various fields such as analytical chemistry, life sciences and more for 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 would be more beneficial for research applications. Being able to look at these components in a synthetic environment and being able to simulate biological processes allows us to have a comprehensive understanding of the human body to create more effective drugs, implants, etc. Specifically, studying cellular migration is important in order to better understand how chronic conditions occur, and to better evaluate treatments for these conditions [1]. Neutrophils and T-cells immune 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.


Materials and Methods:: Multiple designs for microfluidic devices were created and a final design was decided based on a determined set of customer needs: the design’s ability to combine 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. 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.

Results, Conclusions, and Discussions:: At this stage, a prototype was developed based on our chosen design which would help us best address our clinical needs. 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 to the chemokine gradient or the shear flow, the T-cells will go into the respective outlets. If the influence of the shear flow is greater than that of the chemokine gradient, the T-cells will migrate into the shear flow outlet. Similarly, if the influence of the chemokine gradient is greater than that of the shear flow, the T-cells will migrate in the direction of the higher concentration of the chemokines. Through determining which cellular migration signal affects T-cells, we can understand the pathophysiology of chronic conditions and create specific therapeutic strategies to target these biological mechanisms. This device is still in the prototype stage, and preliminary data is in the process of being obtained. We aim to have distinct detection of T-cells migration for creation of specific therapeutic interventions that can improve individuals’ quality of living.


Acknowledgements (Optional): : This research is funded by NIH GM143357 to ABJ.


References (Optional): : 1. Theveneau, Eric et al. in Cell Mol Life Sci. (2013)