The miR-146a-5p expression level was inhibited in IPF mice, whereas UC-sEv treatment increased this expression level and decreased the expression of the target genes traf6 and irak1. Our data suggested that miR-146a-5p expression levels markedly decreased after BLM injury and that their expression was augmented in lung tissue or cells after UC-sEv treatment. The gene discussed is IRAK1; the disease is idiopathic pulmonary fibrosis.