biostudies-literatureUnknown12(1)Campo IBoehringer IngelheimAutoimmune pulmonary alveolar proteinosis (aPAP) is a rare lung disorder involving production of autoantibodies against endogenous granulocyte-macrophage colony-stimulating factor (GM-CSF). This study aimed to identify biomarkers that could be used to monitor for aPAP, particularly in patients treated with anti-GM-CSF antibodies. This was an exploratory, prospective, observational, single-center study. Pre-specified biomarkers were evaluated between baseline and Day 120 in serum/plasma, whole blood, sputum and exhaled breath condensate from patients with aPAP, healthy volunteers, and patients with chronic obstructive pulmonary disease (COPD) and asthma (not treated with anti-GM-CSF and with no evidence of aPAP). Pulmonary function tests were also performed. Overall, 144 individuals were enScientific reports8708https://www.ebi.ac.uk/biostudies/studies/S-EPMC9130212biostudies-literatureAn exploratory study investigating biomarkers associated with autoimmune pulmonary alveolar proteinosis (aPAP).PMC9130212Gupta AGahlemann MIttrich CSauter WTrapnell BCMeloni FSchoelch CCampo IfalseAn exploratory study investigating biomarkers associated with autoimmune pulmonary alveolar proteinosis (aPAP).Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare lung disorder involving production of autoantibodies against endogenous granulocyte-macrophage colony-stimulating factor (GM-CSF). This study aimed to identify biomarkers that could be used to monitor for aPAP, particularly in patients treated with anti-GM-CSF antibodies. This was an exploratory, prospective, observational, single-center study. Pre-specified biomarkers were evaluated between baseline and Day 120 in serum/plasma, whole blood, sputum and exhaled breath condensate from patients with aPAP, healthy volunteers, and patients with chronic obstructive pulmonary disease (COPD) and asthma (not treated with anti-GM-CSF and with no evidence of aPAP). Pulmonary function tests were also performed. Overall, 144 individuals were en2022-01-01T00:00:00Z2022 May2026-05-09T18:56:20.475Z2025-04-05T20:39:51.993ZS-EPMC91302123561026810.1038/s41598-022-11446-8