title: Functional changes in neutrophils and psychoneuroendocrine responses during 105 days of confinement.
abstract: The innate immune system as one key element of immunity and a prerequisite for an adequate host defense is of emerging interest in space research to ensure crew health and thus mission success. In ground-based studies, spaceflight-associated specifics such as confinement caused altered immune functions paralleled by changes in stress hormone levels. In this study, six men were confined for 105 days to a space module of ~500 m(3) mimicking conditions of a long-term space mission. Psychic stress was surveyed by different questionnaires. Blood, saliva, and urine samples were taken before, during, and after confinement to determine quantitative and qualitative immune responses by analyzing enumerative assays and quantifying microbicide and phagocytic functions. Additionally, expression and shedding of L-selectin (CD62L) on granulocytes and different plasma cytokine levels were measured. Cortisol and catecholamine levels were analyzed in saliva and urine. Psychic stress or an activation of the psychoneuroendocrine system could not be testified. White blood cell counts were not significantly altered, but innate immune functions showed increased cytotoxic and reduced microbicide capabilities. Furthermore, a significantly enhanced shedding of CD62L might be a hint at increased migratory capabilities. However, this was observed in the absence of any acute inflammatory state, and no rise in plasma cytokine levels was detected. In summary, confinement for 105 days caused changes in innate immune functions. Whether these changes result from an alert immune state in preparation for further immune challenges or from a normal adaptive process during confinement remains to be clarified in future research.
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: C
authors: C
authors: Strewe
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: F
authors: F
authors: Muckenthaler
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: M
authors: M
authors: Feuerecker
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: B
authors: B
authors: Yi
authors: Institute for Biomedical Problems, Moscow, Russian Federation;
authors: M
authors: M
authors: Rykova
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany; Department of Anesthesiology and Intensive Care Medicine, Neuperlach Hospital, Municipal Hospital Group, Munich, Germany; and.
authors: I
authors: I
authors: Kaufmann
authors: Institute for Biomedical Problems, Moscow, Russian Federation;
authors: I
authors: I
authors: Nichiporuk
authors: Institute for Biomedical Problems, Moscow, Russian Federation;
authors: G
authors: G
authors: Vassilieva
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: M
authors: M
authors: Hörl
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: S
authors: S
authors: Matzel
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany;
authors: G
authors: G
authors: Schelling
authors: Clinic of Anesthesiology and Intensive Care, Klinikum Mannheim, University of Mannheim, Mannheim, Germany.
authors: M
authors: M
authors: Thiel
authors: Institute for Biomedical Problems, Moscow, Russian Federation;
authors: B
authors: B
authors: Morukov
authors: Department of Anesthesiology, Klinikum Groβhadern, University of Munich, Munich, Germany; alexander.chouker@med.uni-muenchen.de.
authors: A
authors: A
authors: Choukèr
mesh_terms: D000223:Adaptation, Psychological / Q000502:physiology; D018480:Astronauts / Q000523:psychology*; D002395:Catecholamines / Q000097:blood; D016207:Cytokines / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007113:Immunity, Innate / Q000276:immunology / Q000502:physiology; D007249:Inflammation / Q000097:blood / Q000276:immunology / Q000523:psychology; D019041:L-Selectin / Q000097:blood / Q000276:immunology; D007958:Leukocyte Count / Q000379:methods; D008297:Male; D009490:Neurosecretory Systems / Q000276:immunology* / Q000502:physiology*; D009504:Neutrophils / Q000276:immunology* / Q000502:physiology*; D013026:Space Flight / Q000379:methods; D013315:Stress, Psychological / Q000276:immunology / Q000523:psychology
chemical_list: D002395:Catecholamines; D016207:Cytokines; D019041:L-Selectin; D006854:Hydrocortisone
keywords: confinement; innate immune system; spaceflight