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Fighting Flames

Route of circulation of immune progenitor cells from the bone marrow to sites of inflammation revealed

20 June 2021

Fighting Flames

Our bodies must respond swiftly to infection, calling upon fleets of immune cells that migrate towards a pathogen. Yet as the immune defenders pile in, the surrounding tissue swells with inflammation that's both necessary and potential harmful. To keep inflammation in check, researchers find our bodies produce a balance of pro- and anti-inflammatory cells. Pictured with a high-powered microscope inside this mouse’s thigh bone (highlighted in turquoise with its cell nuclei in blue), we see the likely route that progenitor cells – destined to become anti-inflammatory cells – take as they leave the bone marrow. Guided by a series of chemical signals triggered by the raging immune battle, the cells migrate through a network of lymphatic vessels (red) towards the site of infection where they calm the inflammation. Exploring these chemical changes may one day help to prevent over-zealous immune responses, avoiding conditions like sepsis.

Written by John Ankers

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