简介

Aging has dramatic impacts on all aspects of the immune response. Age-related changes result in significantly reduced immune responses, with lower antibody titers and reduced antibody affinity. My laboratory is interested in determining the specific immune cell types impacted by aging and the mechanisms responsible for these changes. We have focused on CD4 T cells, which are significantly impacted by aging, especially with regards to their ability to differentiate into follicular helper T cells and how this impacts protective antibody production. Using a mouse model of influenza infection, we have shown that these age-related declines in CD4 T cell function have a negative impact on immune responses to both infection and vaccination. Recent studies have determined that age-related defects in CD4 T cell responses are due to both intrinsic changes in CD4 T cell function as well as disruptions in the microenvironment and chemokine production in secondary lymphoid organs. This results in reduced follicular helper T cell function and poor antibody responses. Current studies are examining the mechanisms involved in this defect. We are also exploring how this defect may be overcome with more potent adjuvants or enhanced T cell priming. Our goal is to determine the most efficient way to enhance the efficacy of influenza vaccines for the elderly.