Biological System
Immune & Inflammatory Response
How the body's defense system shifts during spaceflight
Overview
The immune system is the body's defense network — a complex web of cells and proteins that identify and neutralize threats. During spaceflight, this system undergoes measurable shifts. The Inspiration4 crew showed changes in circulating cytokine levels, white blood cell composition, and T/B-cell receptor repertoire diversity, all measured at multiple timepoints before, during (proxied by R+1), and after the 3-day mission.
Key findings
- Cytokine levels (TNFα, IL-6, IL-1β) showed individual-specific trajectories — no uniform crew-wide pattern.
- TCR clonal diversity, measured via VDJ repertoire sequencing, shifted acutely at R+1 and began recovering by R+45.
- WBC and neutrophil counts tracked similarly to known short-duration spaceflight patterns.
- All observations reflect direction of change from each individual's own L-44 baseline — not a population reference.
Individual trajectories
fold-change from L-44 baseline · n=4Lines show fold-change from each crew member's L-44 baseline. Shaded band = typical reference range from OSD-575 data files.
Immune & Inflammatory Response · C001
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Immune & Inflammatory Response · C002
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Immune & Inflammatory Response · C003
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Immune & Inflammatory Response · C004
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Related dashboard domains
How to read this page: These findings describe four individuals at one point in time. No finding should be generalized to spaceflight health broadly. Individual differences dominate the signal. Fold-changes labeled “2× individual baseline” use derived thresholds, not clinical cutoffs.