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Published on: April 4, 2019
Immune Cell Dysregulation in Hindlimb Unloading Mouse Model: Implications for Space Applications
Sadegh Masoudi1, Mehdi Kalani2, Ali Alavianmehr3
1Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
Journal of Biomedical Physics & Engineering
|August 12, 2026
Summary
Hindlimb unloading in mice, a model for microgravity, reduces T cell proliferation and cytokine production, impacting immune function. This suggests potential risks for astronaut health during space missions.
Area of Science:
- Space biology
- Immunology
- Space medicine
Background:
- Hindlimb unloading (HU) in mice simulates microgravity's effects.
- Microgravity significantly impacts the immune system.
- Understanding immune cell function during space missions is crucial for astronaut health.
Purpose of the Study:
- To evaluate microgravity's effects on neutrophils and T cells.
- To compare immune cell activity in HU mice versus control mice.
Main Methods:
- Used 10 HU male BALB/c mice and 10 controls.
- Assessed neutrophil-to-lymphocyte ratio (NLR) and neutrophil function (DHR assay).
- Evaluated T cell proliferation (CFSE-dilution) and cytokine production (IL-4, IFN-ɣ) via flow cytometry.
Main Results:
- Neutrophil ROS production was unchanged, but NLR was higher in HU mice.
- T cell proliferation (CD4+ and CD8+) was reduced in HU mice.
- IL-4 and IFN-ɣ production by T cells significantly decreased in HU mice.
Conclusions:
- Hindlimb unloading impairs immune cell function, reducing cytokine production and T cell proliferation.
- Increased NLR in HU mice may indicate heightened inflammation.
- Findings are vital for space biology and medicine, ensuring astronaut health.
