MUC5AC and chronic obstructive pulmonary disease: In another mouse model of cigarette smoke extract and porcine pancreatic elastase-induced COPD studied by Kim et al. [10], the probiotic Lactiplantibacillus plantarum KF511 was shown to reduce pulmonary inflammation, attenuate lung tissue damage and mucin hypersecretion, suppress immune cell infiltration, and decrease the production of matrix metalloproteinases, cytokines, and chemokines via inhibition of the phosphorylation of p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK).