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Cigarette smoke (Cs) inhalation is a main reason to develop chronic obstructive pulmonary disease (COPD), characterised by degradation of alveoli, mucus hypersecretion, emphysema development and inflammation [1]. The pathophysiology of COPD is not well understood so the mechanisms that underlie various components of COPD need to be modelled in vitro, specifically using Cs. We assessed the pathophysiological effects of Cs and Cs condensate (Csc) on fresh human lung tissue. Human Precision Cut Lung Slices (PCLS) were exposed to Csc submerged or whole Cs in an Air-Liquid Interface using the in vitro exposure device P.R.I.T.® ExpoCube®. Cytotoxicity, release of cytokines and extracellular matrix (ECM) proteins were measured and gene expression analysis upon RNA isolation from PCLS was performed. PCLS exposed to Csc or Cs showed concentration-dependent loss of tissue viability. Gene expression analysis upon RNA isolated from lung tissue exposed to nontoxic doses of Csc of literature-based COPD-relevant genes indicate damage of epithelium by upregulation of genes involved in tissue injury (e.g. mmp) and specific metabolic activity (e.g. cyp1a1). Samples exposed to control substance LPS did not show increased expression in emphysema associated genes but in genes indicating inflammation (e.g. il-6). These data can be supported by increased production of proteins related to the extracellular matrix (e.g. MMP9, RAGE) and inhibited expression in pro-inflammatory cytokines after Cs exposure in an air-liquid culture. Supportive results were presented in BAL samples from COPD subjects showing markers of apoptosis [2]. These results indicate that early stages of Cs induced lung tissue changes are primarily not provoked by immunological processes but by apoptosis, increased specific metabolic activity and damage of the epithelium. [1] Hodge, S. et al. (2005). ERJ 25 (3), S. 447-454. [2] Shaykhiev, R.; Crystal, R. (2014). AnnalsATS 11 Suppl 5, S252-8.

Forced expiratory volume in 1 second (FEV1 ) from spirometry is the most commonly used parameter to detect early allograft dysfunction after lung transplantation (LTx). There are concerns regarding its sensitivity. Nitrogen-multiple breath washout (N2 -MBW) is sensitive at detecting early global (lung clearance index [LCI]) and acinar (Sacin ) airway inhomogeneity. We investigated whether N2 -MBW indices indicate small airways pathology after LTx in children with stable spirometry. Thirty-seven children without bronchiolitis obliterans syndrome [BOS] at a median of 1.6 (0.6-3.0) years after LTx underwent N2 -MBW and spirometry, 28 of those on 2 occasions (≤6 months apart) during clinically stable periods. Additional longitudinal data (11 and 8 measurements, respectively) are provided from 2 patients with BOS. In patients without BOS, LCI and Sacin were significantly elevated compared with healthy controls. LCI was abnormal at the 2 test occasions in 81% and 71% of patients, respectively, compared with 30% and 39% of patients with abnormal FEV1 /forced vital capacity (FVC). Correlations of LCI with FEV1 /FVC (r = 0.1, P = .4) and FEV1 (r = -0.1, P = .6) were poor. N2 -MBW represents a sensitive and reproducible tool for the early detection of airways pathology in stable transplant recipients. Moreover, indices were highly elevated in both patients with BOS. Spirometry and LCI showed poor correlation, indicating distinct and complementary physiologic measures.

Background: Human Respiratory Syncytial virus (HRSV) is a major cause of respiratory disease young children and is known as a risk factor for asthma. HRSV and the viral mimic Poly I:C activate toll‐like receptor 3 (TLR3), initiating an innate response with release of immune mediators, e.g. interferon gamma‐induced protein 10 (IP‐10). In this work, we aimed to perform an ex vivo HRSV infection in precision‐cut lung slices (PCLS) from human, rhesus, and cynomolgus macaques, comparing whenever possible the response with the viral surrogate poly I:C. Method: PCLS containing airways were prepared from lung sections of human, rhesus, and cynomolgus macaques. The slices were inoculated with HRSV‐A2 106 IU/mL, UV‐inactivated HRSV, or vehicle control for 48 hours. Macaque slices were also incubated with Poly I:C 100 mg/mL with and without the immunosuppressive dexamethasone 50 mg/mL. Viral replication, tissue viability, and immune response assays were assessed in supernatants, lysates, or slices. Results: The inoculum infectivity of 106 IU/mL as well the UV‐inactivation were confirmed by plaque‐assay on Hep‐2 cells Immunofluorescence staining using a FITC‐labeled anti‐RSV showed the presence of infected macrophages in PCLS, but not in mock infected samples. HRSV stimulation slightly decreased tissue viability, as seen by Live/DEAD staining and LDH assay. The viral infection increased IP‐10 production in PCLS of human, rhesus, and cynomolgus macaques, reaching respectively 13.3, 3.4, and 1.7 fold‐increase in comparison to the vehicle controls. Poly I:C stimulation caused IP10 response comparable to HRSV in rhesus and cynomolgus PCLS. The IP‐10 production ratio comparing HRSV/Poly I:C was 1.1 in rhesus and 0.9 in cynomolgus PCLS. Conclusion: HRSV infects ex vivo PCLS of human and non‐human primates, inducing the release of the pro‐inflammatory chemokine IP‐10. This response is comparable to the viral surrogate poly I:C. In the future, these systems can be used to further investigate host response to HRSV, especially in the context of asthma development.

Background Investigation of basic chronic inflammatory mechanisms and development of new therapeutics targeting the respiratory tract requires appropriate testing systems, including those to monitor long- persistence. Human precision-cut lung slices (PCLS) have been demonstrated to mimic the human respiratory tract and have potential of an alternative, ex-vivo system to replace or augment in-vitro testing and animal models. So far, most research on PCLS has been conducted for short cultivation periods (≤72 h), while analyses of slowly metabolized therapeutics require long-term survival of PCLS in culture. In the present study, we evaluated viability, physiology and structural integrity of PCLS cultured for up to 15 days. Methods PCLS were cultured for 15 days and various parameters were assessed at different time points. Results Structural integrity and viability of cultured PCLS remained constant for 15 days. Moreover, bronchoconstriction was inducible over the whole period of cultivation, though with decreased sensitivity (EC501d = 4 × 10−8 M vs. EC5015d = 4 × 10−6 M) and reduced maximum of initial airway area (1d = 0.5% vs. 15d = 18.7%). In contrast, even though still clearly inducible compared to medium control, LPS-induced TNF-α secretion decreased significantly from day 1 to day 15 of culture. Conclusions Overall, though long-term cultivation of PCLS need further investigation for cytokine secretion, possibly on a cellular level, PCLS are feasible for bronchoconstriction studies and toxicity assays. Electronic supplementary material The online version of this article (doi:10.1186/s12995-017-0158-5) contains supplementary material, which is available to authorized users.