Dr. Campisi focuses on understanding immune system functioning, particularly with respect to how biological factors (e.g., aging) and lifestyle behaviors (stress, physical activity status, diet) modulate immune outcomes and interact. Chronic stress is well known to have deleterious consequences on immune system function. However, recent evidence suggests that acute stress may actually enhance numerous features of the immune system. A growing body of research suggests that the impact of stress on measures of immunity can be changed by the physical activity status of an organism. For example, physical activity can buffer the suppressive effects of stress on acquired immunity while further enhancing the positive effects of stress on innate immunity. Research projects focus on understanding the mechanisms mediating these interactions.