MCOLN3 and pulmonary emphysema: To better understand the mechanism underlying the observed changes in lung function in Trpml3−/− mice and to examine whether there is a direct link between TRPML3 expression/function in AMΦ and the observed emphysema phenotype, we performed different assays using BALF samples and AMΦ isolated from Trpml3−/− and WT mice.