Impact of long-duration spaceflight on the function of B-cells and biomarkers of inflammation
We are investigating the impact of long-duration spaceflight on immune proteins in blood collected from astronauts on the International Space Station.
Long-duration spaceflights have been associated with profound dysregulation of the immune system. This can jeopardise crew safety and mission success. To carry out successful exploration-class missions to Mars or other objects near Earth, we need to better understand the impact of long-duration spaceflight on the immune system. This will enable us to evaluate the risks of crew adverse health events. Recent studies have examined the impact of long-duration spaceflight on specific markers of adaptive and innate immunity. But no study has characterised humoral immunity and serological markers of B-Cell function yet.
This project aims to characterise acute and chronic changes in immune proteins, indicative of overall B-cell function. We will do this by analysing archived plasma and saliva samples collected during long-duration spaceflight.
We collected plasma and saliva samples from 23 astronauts:
- before flight
- during flight (early, mid and late)
- immediately upon return to Earth
- during recovery period (R + 18, R + 33, R + 66)
We also took plasma and saliva samples from six age/gender-matched healthy ground-based control subjects.
One of the project's key focuses is to investigate plasma Kappa and Lambda free light chains. These represent a near real-time indication of B-Cell activations status. We will measure these using a recently developed ELISA from Abingdon Health, Oxford, UK.
We will calculate Cystatin C derived estimates of Glomerular Filtration Rate (eGFR). This will help to account for fluctuations in renal function (the principle mechanism of free light chain clearance from the body).
Finally, we will assess total immunoglobulins and isotype switching. We will use commercially available ELISA kits to measure the changes in total plasma IgA, IgG and IgM throughout the mission.
Our findings will form the basis of understanding how long-duration spaceflight affects humoral immunity. This, in turn, will inform how infection risk may be increased among astronauts on future missions to Mars.