Experiment NKA

The goal of this experiment is to determine whether natural killer (NK) cell activity is altered in microgravity.
NK cells are an important part of the immune system, since they are pre-programmed to destroy virus infected cells and cancerous cells. Therefore it is important for long term space exploration to characterize whether microgravity and spaceflight conditions alter the function of NK cells, as this may affect the frequency at which latent virus infections become reactivated or tumours develop in a long duration space missions.
The experiment will measure the ability of NK cells from human peripheral blood to lyse K562 target cells. This will be achieved by using 3H-Uridine labelled formalin fixed K562 cells which will be mixed with NK cells in-flight, then incubated for 24h. At the end of the incubation period cells will be filtered from the medium in-flight, then transferred to refrigerated stowage until post flight analysis. Post-flight, the amount of radiolabel in the intact target cells (on the filter) and released from lysed cells (in the medium) will be measured, as well as cytokine production by the target cells.

Objective:

Determine whether natural killer (NK) cell activity is altered in microgravity.

Tasks:

Quantify the activity of NK cells against K562 target cells under microgravity and 1g conditions;
Quantify cytokine release from NK cells under microgravity and 1g conditions;
Clearly distinguish the effect of microgravity from other spaceflight factors by the use of an on-board 1g centrifuge.