Astronauts' immune response halved for crew members on ISS compared to pre-flight levels (and control subject) of NK-cell function - they also find that veteran crew members' drops are less severe compared to rookies (suggesting higher stress in rookies or age may be at play)

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Astronauts' immune response halved for crew members on ISS compared to pre-flight levels (and control subject) of NK-cell function - they also find that veteran crew members' drops are less severe compared to rookies (suggesting higher stress in rookies or age may be at play)