Abstract
Although immune dysfunction by space conditions has been reported postflight, as well as during ground-based
experiments, the cause(s) and nature of the immunological changes are not completely understood. Microgravity
has been suggested as one of the factors responsible for the observed immune dysregulation. The goal of
this study was to assess immune changes in simulated microgravity (s-mG) using an in vitro cytokine release
assay. The effect of s-mG provided by the desktop random positioning machine on cell-mediated immunity was
examined by analyzing interleukin 2 (IL-2), interferon-g (IFN-g), tumor necrosis factor alpha (TNF-a), and
interleukin 10 (IL-10), in response to immune cell stimulation in whole blood samples (n = 10). Stimuli used
were bacterial recall antigens, pokeweed mitogen (PWM), lipopolysaccharide (LPS), or heat-killed Listeria
monocytogenes (HKLM). S-mG caused an overall inhibition of the IL-2 and IFN-g responses to recall antigen
and mitogen stimulation. More specifically, s-mG most strongly influenced the levels of all four cytokines
elicited by bacterial recall antigen stimulation. In contrast, HKLM-induced TNF-a secretion was elevated. The
average concentrations of TNF-a in response to PWM and LPS and IL-10 release stimulated by PWM, LPS,
and HKLM were not significantly altered by s-mG. However, a variable response between individual subjects
could be observed. In conclusion, our results demonstrate that the in vitro cytokine release assay can detect
gravity-related immune alterations. Furthermore, the use of multiple stimuli and the associated changes in
cytokine secretion has the potential to reveal information on the underlying mechanisms affected by s-mG.
Details
Original language | English |
---|
Journal | Journal of Interferon and Cytokine Research |
---|
Volume | 37 |
---|
Issue number | 12 |
---|
DOIs | |
---|
Publication status | Published - 1 Dec 2017 |
---|