Recent work suggests a novel mechanism by which macrophages seek out damaged tissues: they sense hydrogen peroxide released by tissue damage and navigate by travelling up the gradient of H2O2. What is the mechanism? H2O2 is known to activate a thermally sensitive ion channel, TRPM2, and an influx of calcium through this ion channel may “steer” a macrophage towards a site of tissue damage. The project will use mRNA sequencing, bioinformatics and both in vitro and in vivo experiments to establish how macrophages detect hydrogen peroxide and how important this mechanism in navigating towards damaged tissue.
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