STAT3 and STAT6 activation in lung tissues correlates with inflammatory and clinical traits in COPD

This study shows that activation of the JAK/STAT pathway is increased in the lungs of patients with COPD, with distinct associations with inflammatory phenotypes. STAT3 activation is enhanced particularly in alveolar macrophages and is linked to higher blood neutrophil counts and the presence of chronic bronchitis, while STAT6 activation is specific to COPD and correlates with eosinophilic inflammation in lung tissue and blood, as well as with chronic bronchitis. No significant differences were observed for STAT1. Overall, these findings support the existence of biologically distinct inflammatory endotypes in COPD and highlight the JAK/STAT pathway as a potential target for precision therapeutic approaches.