Pseudomonas aeruginosa induces the generation of pathogenic IFNγ(+)Th17 cells that promote lung damage and chronic inflammation in cystic fibrosis.

Pseudomonas aeruginosa in cystic fibrosis lungs induces pathogenic IFNγ(+)Th17 cells that directly promote lung damage and chronic inflammation.

• Why it matters: Understanding how P. aeruginosa influences immune responses in CF is crucial because these bacteria persist and exacerbate lung damage, yet the specific immune mechanisms involved are unclear.
• What they did: The study analyzed lung samples from CF patients, identifying two pathogenic Th17 subsets, Th1/17 + and pTh17 cells, that derive from conventional Th17 precursors and are enriched in P. aeruginosa-colonized lungs, using transcriptomic and T cell receptor profiling.
• The result: P. aeruginosa strains induce a cytokine axis that promotes IFNγ + Th17 differentiation, reprogramming protective Th17 cells into pathogenic subsets, which may offer targets for CF-specific immunotherapies.