Michael Hogan, PhD, Postdoctoral Fellow Children's Hospital of Philadelphia Area of Research: All Cancers Helper T cells are required for protective immune responses against cancer and infectious diseases, and they are also critical for the success of new cancer immunotherapies. Helper T cells recognize cancerous or infected cells by seeing fragments of abnormal proteins that are displayed on the cell surface via a molecule called MHC-II. Once this occurs, the helper T cells become activated and alert other immune cells to destroy the diseased cells. There is currently a controversy in the field of immunology over the way in which helper T cells recognize diseased cells. Traditionally, it was thought that the protein fragments had to be taken up from the space outside the cell. In contrast, the lab in which Dr. Michael Hogan works recently found that in mice infected with influenza virus, the majority of protein fragments presented by MHC-II actually came from within infected cells. The cellular pathways by which this “alternative” MHC-II presentation occurs are not yet known. Therefore, Hogan is investigating these alternative pathways in greater detail than was possible in previous studies. In addition, he will test the hypothesis that alternative MHC-II presentation leads to a more effective helper T cell response, using influenza virus infection as a model disease. Because helper T cells recognize viral infections and cancer in the same manner, these results should be directly applicable to the development of more effective cancer vaccines and immunotherapies. Projects and Grants Endogenous MHCII presentation: cell biology and functional consequences Children’s Hospital of Philadelphia | All Cancers | 2019 | Laurence Eisenlohr, V.M.D., PhD