Distinct phenotypes of platelet, monocyte, and neutrophil activation occur during the acute and convalescent phase of COVID-19.

SARS-CoV-2 has spread rapidly worldwide, causing the COVID-19 pandemic. Platelet activation and platelet-leukocyte complex formation are proposed to contribute to disease progression. Here, we report platelet and leukocyte activation during acute and convalescent COVID-19 in patients recruited between May-July 2020.

Activity of airway antimicrobial peptides against cystic fibrosis pathogens.

Antimicrobial peptides are important players of the innate host defence against invading microorganisms. The aim of this study was to evaluate the activity of airway antimicrobial peptides against the common cystic fibrosis (CF) pathogen Pseudomonas aeruginosa, and to compare it to the emerging multi-drug resistant CF pathogens Achromobacter xylosoxidans and Stenotrophomonas maltophilia. Clinical bacterial isolates from CF patients were used, and the antimicrobial activity of human beta-defensin 2 and 3, LL37 and lysozyme was evaluated using radial diffusion assay and viable counts.

BPI-ANCA is expressed in the airways of cystic fibrosis patients and correlates to platelet numbers and Pseudomonas aeruginosa colonization.

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.

Heparin-binding protein in sputum as a marker of pulmonary inflammation, lung function, and bacterial load in children with cystic fibrosis.

Background: Cystic fibrosis (CF) is associated with bacterial pulmonary infections and neutrophil-dominated inflammation in the airways. The aim of this study was to evaluate the neutrophil-derived protein Heparin-binding protein (HBP) as a potential sputum marker of airway inflammation and bacterial load.

Methods: Nineteen CF patients, aged 6-18 years, were prospectively followed for 6 months with sputum sampling at every visit to the CF clinic.