Bacterial infections are a significant health concern, made increasingly difficult to treat by antibiotic resistance. Severe bladder infections, or acute cystitis, are a common problem, experienced at by at least 60% of women, yet why the immune system sometimes responds with painful inflammation is poorly understood. In this mouse bladder section, infection with E. coli (in green) attracts immune cells (in red) to the lining of the bladder, aggregating with the bacteria in micro-abscesses (yellow). In mice, cytokine interleukin 1 beta (IL-1β), a protein secreted by immune cells, is responsible for triggering this elevated response; those without IL-1β, or the enzyme responsible for activating it, develop much milder infections. Also found in the urine of patients with acute cystitis, these proteins are promising targets for treatments reining in the immune response in humans too. If successful, modulating immunity could become a key tactic for fighting bacterial infections in the future.
Written by Emmanuelle Briolat
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