Transmission electron microscopy of stable transfected HEK293-cells. Top: overview of one cell showing cytoplasm, containing mitochondria (light grey) and organelles resembling lamellar bodies (dark grey). Bottom: single ‘lamellar bodies resembling organelles’ in higher magnification. The boxed area is shown in the top image as inset in higher magnification. Note the concentric arrangement of the lamellae in the ABCA3-WT strain. Dark appearing lamellae are mostly wound around a centre of less electron density and appear as parallel lines in the high magnification. In the strain G964D these organelles appear less organized: lamellae are often not arranged perfectly parallel (see inset), and the concentric organisation is not as distinct as in the WT.