MUC5B and pulmonary fibrosis: More recently, one study using the ALI culture of human bronchial epithelial cells and a mouse model of lung fibrosis induced by bleomycin reported that MUC5B overproduction led to cilia gene expression in IPF airway epithelial cells, which subsequently enhanced multiciliogenesis, as evidenced by both the number of ciliated cells and the disrupted motile cilia structure 50.