Fig. 2: Lung function parameters in WT and Trpml3^−/− mice (Mcoln3^tm1.2Hels and Mcoln3^tm1.1Jga).

Lung function measurements were performed using the SCIREQs FlexiVent System (see Methods). Different manoeuvres were applied. Single Frequency Forced Oscillation Technique (FOT) allows to study the subject’s response to a sinusoidal waveform, obtaining parameters such as Elastance (E) and Compliance (C). Broadband FOT measures the subject’s response to a signal, including a broad range of frequencies, below and above the subject’s breathing frequency. Outcomes are, e.g., Tissue Elasticity (H). Deep Inflation inflates the lungs to a total lung capacity state. Initial and end volumes are used to calculate Inspiratory Capacity (IC). Pressure-volume (PV) loops capture the quasistatic mechanical properties of the respiratory system such as Quasi-Static Compliance (Cst) and Total Lung Capacity (A). a, b In two different 4–5 months old Trpml3^−/− mouse models on different background, each (BL6 and FVB), a significant reduction of Elastance (E) of the whole respiratory system was observed, whereas the Compliance (C) was significantly increased (basal, untreated). *p < 0.05, **p < 0.01; Student’s t test, unpaired, two-tailed. c Differences of E, C, H, Cst, IC, and A in PBS versus elastase-treated 4–5 months old Trpml3^−/− and WT mice. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001; Two-way ANOVA followed by Tukey’s post hoc test. One single dot corresponds to one mouse, each in a–c. Average values are mean values ± SEM, each. d Pressure-volume (PV) loops of experiments as shown in c. Data are mean ± SEM calculated for each group. e Representative images of H&E-stained lung tissue sections from mouse lungs (BL6 WT and Trpml3^−/−) exposed to Elastase or PBS showing the respective extent of airspace enlargements. Scale bar 100 µm. f Quantification of airspace enlargement as mean linear chord length. Lung tissue sections from 6–8 mice per group were analysed. Each dot corresponds to one biologically independent lung tissue sample. Average values are mean values ± SEM, each. *p < 0.05, ****p < 0.0001; One-way ANOVA followed by Tukey’s post hoc test. Source data are provided as a Source Data file.