The "one airway, one disease" concept in light of Th2 inflammation.

In line with the pathophysiological continuum described between nose and bronchus in allergic respiratory diseases, we assessed whether nasal epithelium could mirror the Type 2 T-helper cell (Th2) status of bronchial epithelium.Nasal and bronchial cells were collected by brushing from healthy controls (C, n=13), patients with allergic rhinitis and asthma (AR, n=12), and patients with isolated allergic rhinitis (R, n=14). Cellular composition was assessed by flow cytometry, gene expression was analysed by RNA sequencing and Th2, Type 17 T-helper cell (Th17) and interferon (IFN) signatures were derived from the literature.Infiltration by polymorphonuclear neutrophils (PMN) in the nose excluded 30% of the initial cohort. All bronchial samples from the AR group were Th2-high. The gene expression profile of nasal samples from the AR group correctly predicted the paired bronchial sample Th2 status in 71% of cases. Nevertheless, nasal cells did not appear to be a reliable surrogate for the Th2 response, in particular due to a more robust influence of the IFN response in 14 out of 26 nasal samples. The Th2 scores in the nose and bronchi correlated with mast cell count (both p<0.001) and number of sensitisations (p=0.006 and 0.002), while the Th17 scores correlated with PMN count (p=0.006 and 0.003).The large variability in nasal cell composition and type of inflammation restricts its use as a surrogate for assessing bronchial Th2 inflammation in AR patients.

SENS-IS, a 3D reconstituted epidermis based model for quantifying chemical sensitization potency: Reproducibility and predictivity results from an inter-laboratory study.

The SENS-IS test protocol for the in vitro detection of sensitizers is based on a reconstructed human skin model (Episkin) as the test system and on the analysis of the expression of a large panel of genes. Its excellent performance was initially demonstrated with a limited set of test chemicals. Further studies (described here) were organized to confirm these preliminary results and to obtain a detailed statistical analysis of the predictive capacity of the assay. A ring-study was thus organized and performed within three laboratories, using a test set of 19 blind coded chemicals. Data analysis indicated that the assay is robust, easily transferable and offers high predictivity and excellent within- and between-laboratories reproducibility. To further evaluate the predictivity of the test protocol according to Cooper statistics a comprehensive test set of 150 chemicals was then analyzed. Again, data analysis confirmed the excellent capacity of the SENS-IS assay for predicting both hazard and potency characteristics, confirming that this assay should be considered as a serious alternative to the available in vivo sensitization tests.