EPS06.2 Immune cell localization in different compartments of human end-stage CF lungs

Abstract

Objectives The localization of immune cells along airways, blood vessels or in parenchyma in CF lung disease has insufficiently been established. A comprehensive quantitative immunohistochemical analysis was performed on lung tissue from CF patients and healthy controls (HC). Methods Sections (8 mm) of lung biopsies of CF patients taken during transplantation (n = 20) and control lung biopsies (n = 22) were stained for Th-lymphocytes (CD4), mast cells (tryptase) and eosinophils (EG-2). Quantification was performed by counting all single cells normalized over total area (mm 2 ) of biopsy (Th cells), or in 10 high power fields averaged per compartment (airways, blood vessels and parenchyma) per subject (mast cells and eosinophils). Results CD4+ T-lymphocyte counts were significantly increased in CF vs. HC (p = 0.001) and were present as dispersed single cells (CF & HC), or organized in follicles mainly situated in parenchyma (predominantly CF). Both total & compartmental mast cell counts were significantly increased in CF vs. HC (all p Conclusion There is an increased presence of Th lymphocytes and mast cells in the end-stage CF lung, albeit in different compartments of the lung. Inflammation was more severe in female CF patients irrespective of FEV 1 , colonization status or genotype, corroborating previous data suggesting a direct deleterious effect of female hormone on inflammation in the CF lung.