FPR1 and autoimmune pulmonary alveolar proteinosis: In APAP-ALI, neutrophils are recruited in response to numerous signals, including tissue damage-associated molecular patterns (DAMPs), particularly mitochondrial formylated peptides,7 which bind to formylated peptide receptor 1 (FPR1), resulting in receptor upregulation, and neutrophil activation17,18 and migration.19