Investigating the role of the S1PR1 endocytosis pathway on T cell migration towards S1P.

Christine Wu


COL 2022


Professor of Pathology and Laboratory Medicine

Project Summary

This summer, I was fortunate to work under the guidance of Dr. Janis Burkhardt at the Children’s Hospital of Philadelphia researching the signaling mechanisms that guide T cell migration.

The protective immune response is dependent on the continuous circulation of T cells in search of foreign invaders. As part of this process, T cells must exit lymphoid organs and traffic into the lymph and blood. This important event is regulated by the binding of sphingosine 1-phosphate receptor 1 (S1PR1) to its ligand, sphingosine 1-phosphate (S1P). Upon binding, S1P is internalized along with its receptor through clathrin-mediated endocytosis. Receptor internalization is typically associated with signal termination. However, in non-hematopoietic cells stimulated by artificial agonists, there is evidence that S1PR1 can continue signaling from endosomes. Thus, for my independent research project, my objective was to investigate the signaling behavior of S1PR1 following internalization. Understanding the nature of S1PR1, as it relates to T cell migration, is crucial to learning what regulates proper immune function.

Through this research project, I had the opportunity to improve my skills in flow cytometry, western blotting, and mouse dissection. However, the most useful skill I learned was how to troubleshoot my procedures when an experiment did not go as planned. For example, when detecting cell-surface receptors using flow cytometry, it is easy to get a false signal due to improper antibody binding. Whenever I got a peculiar result from a flow cytometry experiment, I would make it a habit to include antibody controls in the repeat experiment in order to locate the source of experimental error. Although it can be discouraging at first to receive an inconclusive result, troubleshooting an experiment helps me truly understand the protocol and teaches me what to avoid if I ever plan to run the same procedure in the future.

My experience in the Burkhardt lab has stimulated my interest in interdisciplinary cell biology-immunology research, encouraging me to pursue a PhD in immunology. However, this summer in the lab would not have been the same without the support of the Burkhardt lab team and CURF. I am grateful for the opportunity to have pursued a research project funded by the College Alumni Society Undergraduate Research Grant, and look forward to my future scientific endeavors in the Burkhardt lab this upcoming year.

To see my poster, please visit Penn Presents: