Effect of spaceflight on natural killer cell activity

Abstract

The effects of spaceflight on immune cell function were determined in rats flown on COSMOS 2044. Control groups included vivarium, synchronous, and antiorthostatically suspended rats. The ability of natural killer cells to lyse two different target cell lines was determined. Spleen and bone marrow cells obtained from flight rats showed significantly inhibited cytotoxicity for YAC-1 target cells compared with cells from synchronous control rats. This could have been due to exposure of the rats to microgravity. Antiorthostatic suspension did not affect the level of cytotoxicity from spleen cells of suspended rats for YAC-1 cells. On the other hand, cells from rats flown in space showed no significant differences from vivarium and synchronous control rats in cytotoxicity for K-562 target cells. Binding of natural killer cells to K-562 target cells was unaffected by spaceflight. Antiorthostatic suspension resulted in higher levels of cytotoxicity from spleen cells for 51Cr-labeled K-562 cells. The results indicate differential effects of spaceflight on function of natural killer cells. This shows that spaceflight has selective effects on the immune response.

Effects of Simulated Microgravity on Primary Human NK Cells

“…Similar decreases were also reported in both the cytotoxicity and percentage of NK cells after a 21-day spaceflight (Konstantinova et al, 1995). A study in rats showed that, after long-term spaceflights, the percentage of NK cells is significantly reduced, and NK cell activity is suppressed by 20-85% compared to preflight data (Rykova et al, 1992). Nevertheless, there are also some conflicting results in the literature.…”

Gene Expression Microarrays in Microgravity Research: Toward the Identification of Major Space Genes

“…IL-2 production decreased after space flight for three different T cell subsets (CD3 + , CD4 + and CD8 + ) and IFN-production decreased in the CD4 + subset (Crucian et al, 2000). Spaceflight studies performed with rodents have found that microgravity caused rodents to be more susceptible to infection (Sonnenfeld et al, 1988), inhibited NK cell activity (Rykova et al, 1992), reduced capability for wound healing (Davidson et al, 1999), inhibited INF-production (Gould et al, 1987) and a reduction in lymphoid organ size (Congdon et al, 1996). A study using rhesus monkeys, microgravity inhibited IL-1 production and decreased response to colony stimulating factor (CSF) on bone marrow cells (Sonnenfeld et al, 1996).…”

Effects of Simulated Microgravity on Functions of Neutrophil-like HL-60 Cells

“…Parabolic flight induces an increase in PMN number and the capability of PMNs to produce hydrogen peroxide (H 2 O 2 ) in response to soluble stimuli (Kaufmann et al 2009). These works seemingly indicate that the action of microgravity has enhanced the immune response of PMNs, which is inconsistent with the reduced capability of lymphocytes (Cogoli and Tschopp 1985;Konstantinova et al 1993;Meshkov and Rykova 1995;Mills et al 2002;Mills et al 2008Mills et al , 2013, monocytes (Kaur et al 2005(Kaur et al , 2008Crucian et al 2011), NK cells (Rykova et al 1992;Konstantinova et al 1993Konstantinova et al , 1995Mehta et al 2001), and macrophages (Armstrong et al 1995;Hsieh et al 2005;Ortega et al 2012;Adrian et al 2013;Wang et al 2014Wang et al , 2015Brungs et al 2015;Paulsen et al 2015) under microgravity. The underlying mechanisms for such the difference remain unclear.…”