Abstract
Background: Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene which is expressed in epithelial-line cells, but also in immune cells. Reported T cell abnormalities in CF include dysregulated Th2/Th17 cells and an impairment of regulatory T cells (Tregs).
Aims and objectives: We hypothesized that there would be effects on the composition of lymphocyte subsets in patients with CF (PWCF) receiving CFTR modulators.
Methods: Peripheral blood mononuclear cells and serum samples were collected from 108 PWCF and 40 patients with non-CF bronchiectasis between March and October 2020. Samples were analysed for peripheral blood lymphocytes subsets and systemic T helper cell-associated cytokines using flow cytometry.
Results: 55/108 (51%) of PWCF received either mono or dual-combination CFTR modulator therapy. There were no differences in proportions of analysed T cell subsets or cytokines between PWCF who were versus were not receiving CFTR modulators. Additional analysis revealed lower percentages of Tregs in PWCF with chronic Pseudomonas aeruginosa lung infection (8.2% vs. 7.5% of T helper cells, p=0.028). This effect was not observed in patients with non-CF bronchiectasis. Tregs with CD39 expression were higher in patients with non-CF bronchiectasis versus PWCF (60.2% vs. 50.4% of Tregs; p<0.001). Patients with non-CF bronchiectasis tended to have higher percentages of Th2- and Th17-cells and higher levels of peripheral cytokines versus PWCF.
Conclusions: Chronic Pseudomonas aeruginosa lung infection appears to impair Tregs in PWCF-a phenomenon that is potentially specific to CF.
Footnotes
Cite this article as: European Respiratory Journal 2021; 58: Suppl. 65, OA1499.
This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2021