APOA1 and pulmonary fibrosis: Accumulation of foamy cells in smokers – a strong comorbidity factor in lung infections (Wilson et al., 2011) – reflects impaired lipid cellular metabolism, as reduced levels of apolipoprotein A1 (ApoA1) are found in the bronchoalveolar lavage fluid of patients with idiopathic pulmonary fibrosis (IPF) (Kim et al., 2010).