Gisela Hovold1, Ulrika Lindberg2, Johanna K Ljungberg1, Oonagh Shannon1, Lisa I Påhlman3. 1. Lund University, Department of Clinical Sciences Lund, Division of Infection Medicine, Lund, Sweden. 2. Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Respiratory Medicine and Allergology, Lund, Sweden. 3. Lund University, Department of Clinical Sciences Lund, Division of Infection Medicine, Lund, Sweden; Skåne University Hospital, Division for Infectious Diseases, Lund, Sweden. Electronic address: lisa.pahlman@med.lu.se.
Abstract
BACKGROUND: Autoantibodies to bactericidal/permeability-increasing protein (BPI), BPI-ANCA, are often present in serum of patients with cystic fibrosis (CF), and correlate to airway colonization with Pseudomonas aeruginosa. The aim of the study was to investigate if BPI-ANCA IgA is also present in the airways of CF patients, and if its presence correlates with neutrophil counts, platelets, and P. aeruginosa DNA in sputum. METHODS: BPI-ANCA IgA was quantified in serum and sputum samples from adult CF patients (n = 45) by ELISA. Sputum neutrophil counts, platelets, and platelet-neutrophil complexes were assessed by flow cytometry, and P. aeruginosa DNA was analysed with RT-PCR. RESULTS: Serum BPI-ANCA IgA was present in 44% of the study participants, and this group also had significantly enhanced BPI-ANCA levels in sputum compared to serum negative patients. Sputum levels of BPI-ANCA IgA correlated with P. aeruginosa DNA (r = 0.63, p = 0.0003) and platelet counts in sputum (r = 0.60, p = 0.0002). CONCLUSIONS: BPI-ANCA is expressed in the airways of CF patients and correlates with P. aeruginosa load and platelet counts, suggesting a link to airway inflammation and mucosal immunity.
BACKGROUND: Autoantibodies to bactericidal/permeability-increasing protein (BPI), BPI-ANCA, are often present in serum of patients with cystic fibrosis (CF), and correlate to airway colonization with Pseudomonas aeruginosa. The aim of the study was to investigate if BPI-ANCA IgA is also present in the airways of CFpatients, and if its presence correlates with neutrophil counts, platelets, and P. aeruginosa DNA in sputum. METHODS:BPI-ANCA IgA was quantified in serum and sputum samples from adult CFpatients (n = 45) by ELISA. Sputum neutrophil counts, platelets, and platelet-neutrophil complexes were assessed by flow cytometry, and P. aeruginosa DNA was analysed with RT-PCR. RESULTS: Serum BPI-ANCA IgA was present in 44% of the study participants, and this group also had significantly enhanced BPI-ANCA levels in sputum compared to serum negative patients. Sputum levels of BPI-ANCA IgA correlated with P. aeruginosa DNA (r = 0.63, p = 0.0003) and platelet counts in sputum (r = 0.60, p = 0.0002). CONCLUSIONS:BPI-ANCA is expressed in the airways of CFpatients and correlates with P. aeruginosa load and platelet counts, suggesting a link to airway inflammation and mucosal immunity.