Christopher B. Medina, PhD, CRI-Bristol Myers Squibb Postdoctoral Fellow Emory University Area of Research: All Cancers Dr. Medina is supported by the CRI Irvington Postdoctoral Fellowship to Promote Racial Diversity. T cells are immune cells in our body that can kill cells that have become infected or cancerous. However, when they are constantly exposed to a threat, such as cancer, they can get overactivated and then become exhausted and dysfunctional. By blocking immune checkpoints like PD-1, immunotherapy can prevent this exhaustion and enable T cells to eliminate tumors in some patients, but new checkpoint targets are needed to help more patients. To that end, Dr. Christopher Medina—an inaugural fellow in the CRI Irvington Postdoctoral Fellowship to Promote Racial Diversity—is exploring new immune checkpoints found on specialized “stem-like” T cells that are critical for anti-cancer immune responses.Specifically, Medina seeks to define the mechanisms of two new classes of inhibitory molecules that are predominantly expressed on these stem-like T cells, which were first identified by his postdoctoral sponsor, T cell exhaustion pioneer Dr. Rafi Ahmed. To determine the importance of the different receptors—including a ‘non-classical’ lipid receptor—he is deleting them individually and then monitoring the impact on cell function and disease control, against both cancer and viruses. Overall, Medina’s research aims to provide insight into two unexplored classes of immune checkpoints and thereby identify potential targets for immunotherapy in the clinic. Projects and Grants Defining the unique classes of inhibitory receptor molecules during CD8+ T cell exhaustion Emory University | All Cancers | 2021 | Rafi Ahmed, PhD
