Evaluation of Stress and Immunity
From previous studies, the capability of a human being to defend themselves against infections showed clear changes in response to simulated weightlessness or confinement on earth. Interestingly, these changes appeared to be associated with mental stress experienced by the participating individuals.
This project aims to asses the impact of long term confinement on stress-associated immune responses. Determination of reactivity towards bacterial, viral and fungal antigens will be assessed using blood samples from the crew members. One of the major defence mechanisms of the human immune system is white blood cells (“leukocytes”). These cells might become either “over-activated” or “depressed” and such a situation may render the organism more susceptible to tissue damage by “over-activated” cells and infections by “depressed” cells, respectively.
To test for possible unwanted effects on the neuroendocrine system and on immune response, blood, saliva, and urine samples will be analysed, as well as parameters from exhaled breath, for indications of cellular stress and tissue damage. Additional verification of these effects on cellular metabolism will be determined by measuring elements such as blood purines.
The functional changes or alterations of immunity will be correlated to stress responses determined by stress tests, measurement of neuropeptides (which are neural regulators) and ’new’ stress hormones like endogenous cannabinoids. Metabolic changes and the physical adaptation process to long term confinement will be also assessed and correlated with changes in immune response.
This project will help to provide a better estimate of the overall effects of extreme long-term confinement on immune response and provide the basis for the development of pharmacological tools to counter unwanted immunological side effects during long-duration space missions.
Science Team: Alexander Chouker (DE) et al.