ABCA1 and sarcoidosis: Some examples are ABCA1 and ABCG1, downregulated in lung-resident immune cells from patients with sarcoidosis (Barna et al., 2016); compromised activity of the transcription factor liver X receptor (LXR); reduced plasma levels of alveoli-derived cholestenoic acid in patients with TB, emphysema as well as sarcoidosis (Babiker et al., 1999) and the absence of ABCG1 expression in PAP (de Aguiar Vallim et al., 2017).