STAT3 and allergic disease: The exotoxin CARDS TX released by M. pneumoniae induces “asthma-like” histopathological changes similar to allergic diseases, characterized by elevated eosinophil levels, enhanced Th2 cell responses, increased chemokines expression, increased mucus production, and increased airway resistance (Xu et al., 2024) M. pneumoniae can promoting mucin upregulation via STAT6-STAT3 and epidermal growth factor receptor (EGFR) signaling pathways (Hao et al., 2014), and reduces ciliary clearance rate by directly damaging airway epithelial cells (Lu and Zhou, 2018), leading to mucus blockage.