T cells genetically engineered to express a lab-designed chimeric-antigen receptor, or CAR, offer many patients with blood cancer a new treatment option. But while these T cells may have lifesaving anti-cancer effects, many patients experience a toxic side effect called cytokine release syndrome, or CRS, a body-wide inflammatory response triggered by the engineered T cells. Dr. Sylvain Simon, a postdoctoral fellow in the Hutch’s Riddell Lab, aims to develop safer and more efficient next-generation CAR-T cell therapies that are less likely to cause CRS.
First, he must understand the cellular and molecular changes that underlie CRS. To do so, Simon is studying the blood of CAR-treated patients who experience CRS. One of his main goals is to define the changes in immune cell activity and gene expression associated with CRS development and severity.
In this study, blood samples are taken longitudinally from cancer patients undergoing CAR-T cell therapy. Because patients who receive CAR-T cell therapy also undergo a lymphodepleting chemotherapeutic regimen prior to receiving their engineered T cells, their blood samples often contain few immune cells. To maximize the information obtained from each incredibly valuable sample, he needed an extensive flow cytometry panel that could delineate as many immune-cell subsets as possible. He also needed to create a rigorous protocol that would enable him to generate consistent, comparable results from samples taken over an extended period.
Staff members in the Flow Cytometry core helped Simon identify the best markers and antibodies to include in his panel and create a strategy to assign the right fluorochrome to each marker. Because of their deep experience with the flow cytometer, the shared resource team members were also able to help Simon create a standardized assay. When he saw that certain reagents resulted in poor resolution, the Flow Cytometry team helped him troubleshoot and optimize his panel.