Pendrin has been associated with mucus production in asthma and chronic obstructive pulmonary disease [40], and thus its expression in bronchial epithelium and presence on their released EVs from either condition suggests that it may drive this process in both inflammatory endotypes, and that epithelial EVs could be involved in propagating a mucus hypersecretory phenotype throughout the airways. This evidence concerns the gene SLC26A4 and chronic obstructive pulmonary disease.