I love studying immune responses, especially to viral infections! As a graduate student, under the mentorship of Dr. Jeffery Frelinger at the University of North Carolina, I investigated the direct anti-viral roles of CD4 T cells and how they adopt cytotoxic effector activities. These were significant as they illustrated the plasticity of effector anti-viral CD4 T cells and highlighted that they could develop pathogenic cytolytic capabilities, which was arguably under-appreciated at the time. As a Postdoctoral Fellow in the laboratory of Dr. Rafi Ahmed at Emory University, I performed pioneering studies using MHC class I tetramers and discovered that anti-viral CD8 T cells were not necessarily deleted during chronic viral infections but could instead persist in a functionally inept, exhausted state. This discovery of T cell exhaustion had profound implications for understanding why cell-mediated immunity is ineffective during certain infections and tumors, and for devising checkpoint blockade and other strategies to rejuvenate T cell responses under these conditions. As I established my independent research group at UAB, I went on to show that T cell exhaustion develops in a step-wise and progressive manner and that exhausted T cells are molecularly distinct from their conventional effector and memory counterparts. We also determined how anti-viral CD4 T cells help CD8 T cell responses via the manufacture of IL-21. Our interest in anti-viral CD8 T cell responses goes beyond T cell exhaustion. In published and ongoing studies we are defining the parameters that dictate the development of highly successful, protective CD8 T cell populations, including tumor reactive cells. Our current interests include determining how the functional diversity of the CD8 T cell pool is controlled and contributes to infection and tumor clearance, which is important for the development of immunotherapeutic approaches. In addition to my research activities, I enjoy didactic teaching as well as mentoring undergraduate, graduate, and postdoctoral trainees in the laboratory. I also participate in a variety of committee and service activities that help support my colleagues and foster institutional development.
