Dr Usherwood studies the generation and maintenance of T cell memory. T cells recognized and destroy cells infected with intracellular pathogens such as viruses and are also important in protection against tumor development . A large expansion in the number of virus-specific T cells occurs shortly after virus infection, however most of these cells die after virus clearance has been accomplished. A small residual population of T cells then persists lifelong and forms the basis of immunological memory. Using techniques such as MHC/peptide tetramer staining we can identify these memory cells and interrogate their functional capabilities under different conditions. Our work has shown that costimulation and CD4 T cell help have dramatic effects both on the resting memory population and their ability to mount secondary immune response. We have devised several methods to restore the functional defects present in these cells, and these may represent important new immunotherapies. Another major area of interest in the lab is the impact upon the memory response of a persistent virus infection. We use the murine gammaherpesvirus model system, which represents a low-load persistent virus infection. This virus is also a model for the human gammaherpesviruses, which are significant causes of malignancy and other disease in immunosuppressed patients. Therefore this work has significance both for our understanding of the memory T cell response in general and more specifically how the gammaherpesviruses are controlled, in addition to how and why this control breaks down. Our research has shown several distinct changes occur in the memory response during persistent infection. In models where immune surveillance breaks down we are studying the underlying mechanisms for this breakdown, and developing immune therapies to restore immune surveillance to the virus.
NCI R01 "Immune surveillance in murine gammaherpesvirus infection" NIAID R01 "T cell function in murine gammaherpesvirus infection"
Medical Virology (Medical School) Immune Therapy Advanced Course (MCB graduate program) MCB graduate program core course
University of Cambridge, U.K., Ph.D., 1997 University of Cambridge, U.K., BA 1994
Dr. Usherwood received his B.A. in 1990 in Natural Sciences from the University of Cambridge, U.K. He continued his studies at the University of Cambridge and was awarded his Ph.D. from the Department of Pathology in 1994. From 1994 to 1997 Dr. Usherwood undertook postdoctoral research at the University of Edinburgh, U.K. then he moved to Memphis, TN for further postdoctoral work in the Department of Immunology at St. Jude's Children's Research Hospital. From 1999 to 2001 he held a position as a Research Assistant Member at The Trudeau Institute, NY. He came to Dartmouth in 2001 as an Assistant Professor, then was promoted to Associate Professor in 2007.
Dartmouth Medical School
Borwell Research Building - HB7556 1 Medical Center Drive