While global MFAP4 deficiency does not seem to infer strong phenotypic changes [61,68], it was reported that adult MFAP4-deficient mice exhibit disturbances in pulmonary architecture, characterized by increased inspiratory capacity, decreased alveolar surface area, lowered parenchymal density and emphysema-like airspace enlargement that progresses with age. Here, MFAP4 is linked to pulmonary emphysema.