Figure 3.

Septal microarchitecture of controls (ctrl) and Nedd4-2-deficient (Nedd4-2^−/−) lungs. Stereological data determined at the electron microscopic level are provided in (A–H) and show total volume of AE1 cells within septal walls (A), total volume of AE2 cells within septal walls (B), total volume of interstitial cells (IC) within septal walls (C), total volume of collagen fibrils within septal walls (D), total volume of extracellular matrix without collagen fibrils within septal walls (E), arithmetic mean thickness of the blood–gas barrier, τ(bg) (F), total volume of lamellar bodies (LB) within septal walls (G) and volume-weighted mean volume of the lamellar bodies, ν_V(LB) (H). Individual data and means are presented. The increase in the arithmetic mean thickness of the blood–gas barrier (F) after 12 weeks of Nedd4-2 deficiency is predominantly attributable to an increase of the volume of AE2 cells (B), the volume of interstitial cells (C) and the volume of collagen fibrils (D) by simultaneous decrease of the volume of AE1 cells (A). In addition, there is an increase of the volume of lamellar bodies (G) and the volume-weighted mean volume of the lamellar bodies (H) after 12 weeks of Nedd4-2 deficiency. Statistical analyses were based on a two-way ANOVA taking the factors genetics (G: ctrl vs. Nedd4-2^−/−) and time (7: weeks) into account. Statistically significant differences after adjustment of the p-level for multiple testing using Tukey’s correction.