Title: Stress-induced mucosal immune perturbations and illness

Presenter: Prof. Allan William Cripps, Pro Vice Chancellor (Health)

University: Griffith University

Time: 14:00-15:00, October 25, 2012

Venue: Room A203, Institute of Microbiology, Chinese Academy of Sciences

Abstract: The mucosal immune system protects the host from infection and is a key regulator of homeostasis. Balancing protection and homeostasis is a dynamic process, dependent on anatomical location, infectious pathogen, genetics and environmental influence. This interplay is nowhere more apparent than in the gut, where resident bacteria span a continuum of synbiosis to mutualism to dysbiosis. Perturbations in immune homeostatic mechanisms underpin susceptibility to both infectious and chronic disease. Challenges to immune homeostasis in healthy individuals, such as by physical activity, provide a fertile ground for investigation of the immune mechanisms regulating susceptibility to infectious illness. There is also a need to broaden the parameters examined beyond immunology to include gut flora and neurotransmitters given their immunomodulatory influence. Moderate physical activity is associated with a reduction in the incidence, duration and severity of infectious disease. In contrast, physical inactivity and frequent prolonged intense exercise are associated with increases in illness. We and others have shown that physical activity modulates various aspects of the innate and adaptive immune system. Despite considerable investigation, these changes have only weakly correlated to infection risk. The robustness of the immune system and the large array of cells, molecules and tissues involved in host protection obscure the way in which changes in individual immune parameters are related to infection. Analysis of a range of immune parameters may reveal patterns of change in immune biomarkers that give insight in to the relationship between the immune system and health. These parameters need to include the gut flora and neurotransmitters along with a wide range of cellular and humoral immune biomarkers.