No abstract

Growing up on a dairy farm protects children from allergy, hay fever, and asthma. A mechanism linking exposure to this endotoxin (bacterial lipopolysaccharide)-rich environment with protection has remained elusive. Here we show that chronic exposure to low-dose endotoxin or farm dust protects mice from developing house dust mite (HDM)-induced asthma. Endotoxin reduced epithelial cell cytokines that activate dendritic cells (DCs), thus suppressing type 2 immunity to HDMs. Loss of the ubiquitin-modifying enzyme A20 in lung epithelium abolished the protective effect. A single-nucleotide polymorphism in the gene encoding A20 was associated with allergy and asthma risk in children growing up on farms. Thus, the farming environment protects from allergy by modifying the communication between barrier epithelial cells and DCs through A20 induction.

Although spontaneous protein crystallization is a rare event in vivo, Charcot-Leyden crystals (CLCs) consisting of galectin-10 (Gal10) protein are frequently observed in eosinophilic diseases, such as asthma. We found that CLCs derived from patients showed crystal packing and Gal10 structure identical to those of Gal10 crystals grown in vitro. When administered to the airways, crystalline Gal10 stimulated innate and adaptive immunity and acted as a type 2 adjuvant. By contrast, a soluble Gal10 mutein was inert. Antibodies directed against key epitopes of the CLC crystallization interface dissolved preexisting CLCs in patient-derived mucus within hours and reversed crystal-driven inflammation, goblet-cell metaplasia, immunoglobulin E (IgE) synthesis, and bronchial hyperreactivity (BHR) in a humanized mouse model of asthma. Thus, protein crystals may promote hallmark features of asthma and are targetable by crystal-dissolving antibodies.

Decreased expression of leptin/leptin receptor characterizes severe asthma and is associated with airway remodeling features.

For patients with severe asthma, bronchial thermoplasty reduced the smooth muscle mass of treated airway segments, regardless of the baseline level of muscle mass. Treatment also altered the deposition of collagen. At follow-up, bronchial thermoplasty improved asthma control; however, the limited number of subjects did not allow us to evaluate possible correlations between these improvements and the studied histological parameters. Further studies are needed to confirm these results and evaluate their persistence.

. Live Staphylococcus aureus and bacterial soluble factors induce different transcriptional responses in human airway cells.

No abstract

The relationship between allergic rhinitis and asthma is now established, and most of the clinical, epidemiological and biological data recommend integrated management. Epithelial cells represent the first barrier of the upper and lower respiratory tracts and thus are logical targets for a comprehensive integrated therapeutic approach. This review discusses rhinosinusitis as a co-morbid condition, a precipitating or triggering condition, and an epiphenomenon as an integrated part of the disease. A better understanding and a more pragmatic method of diagnosis and management is needed using cost-effective longterm strategies.Rhinitis and asthma have been evaluated and treated as separate disorders, but recent advances in the understanding and knowledge of the underlying processes have moved current opinion towards the concept of unifying the management of these disorders. The ''united airway disease hypothesis'' proposes that upper and lower airway diseases are both manifestations of a single inflammatory process.