Medical Research Council - London Institute of Medical Sciences

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Mechanisms underlying tissue infiltration by immune cells

25 January 2022

Ready for Actin

Racing to the scene of an infection, immune cells like macrophages need to move through crowded tissues. How do they manage this without getting squished? Researchers studying macrophages in fruit flies (Drosophila melanogaster) find a protein called FOS helps to strengthen each cell’s internal skeleton, creating a ‘tank-like’ shell of actin fibres which cushions the fragile nucleus as the cells push into the tissue. Here macrophages (highlighted in green) spread into (unseen here) embryos under a high-powered microscope – cells with impaired FOS (right) have a weaker protective shell and move more slowly. Humans have similar macrophages and, researchers believe, similar tank-building FOS genes. The new challenge is to support FOS in strengthening our immune cells when invading tumours as a form of cancer immunotherapy.

Written by John Ankers

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