CSF2 and pulmonary alveolar proteinosis: The East Asian predominance of auto-Abs against type II IFN reflects the higher frequency of predisposing HLA-DRB1 alleles in these populations (Chi et al., 2013; Ku et al., 2016; Pithukpakorn et al., 2015), raising questions about possible HLA associations for other anti-cytokine auto-Abs, as suggested for anti–GM-CSF auto-Abs in PAP patients of Japanese ancestry (Sakaue et al., 2021).