Our study was undertaken to establish the kinetics of sCD14 concentrations in BALF in patients with allergic asthma following segmental allergen challenge at different time points (10 min, 18, 42 and 162 h). Moreover, the study attempted to establish stimuli involved in sC14 production and/or shedding, respectively, such as LPS,
which has been shown to increase sCD14 levels in vitro [21] and in vivo [22] and leukotriene D4 (LTD4), which has been implicated in allergic inflammation and the pathogenesis of airway hyperresponsiveness [34]. Furthermore, LTD4 has been shown to induce TNF-α release from macrophages [35] that was inhibited by the leukotriene-receptor antagonist (LTRA) Verlukast [35]. IL-17 has been associated with an OTX015 in vitro increase in IL-8 and GM-CSF production from bronchial epithelial cells [36], the regulation of ICAM-1 expression [37] and the selective recruitment of neutrophils [38]. Moreover, it plays a role in the LPS-induced chemotaxis of neutrophils into the airways after LPS inhalation [39] and increases after organic dust inhalation in healthy subjects [40]. We therefore investigated whether IL-17 might influence sCD14 production in cell cultures. Eighteen patients with allergic asthma (nine men and nine women), mean age 26.3 ± 5.4 years with a duration of asthma for more than 2 years (mean duration 11.7 ± 5.2 years), were studied. Bronchial asthma had previously Apoptosis Compound Library been diagnosed
by an independent physician. Each patient had a positive skin prick test to either birch pollen (n = 8), rye pollen (n = 3), or house dust mite allergen (n = 7) extracts (Allergopharma, Reinbek, Germany), and all had either elevated total IgE levels (293.6 ± 233.1 kU/l) and / or elevated specific IgE levels (32.2 ± 49.1 kU/l) (Kabi Pharmacia CAP System, Uppsala, Sweden) to their respective allergen as well as a history of reversible bronchoconstriction after inhalation of these particular allergens. Obeticholic Acid nmr There was no history or clinical evidence in any of the patients, suggesting a respiratory tract infection prior to or at the time of segmental
allergen challenge. All patients were non-smokers. Baseline FEV1 (forced expiratory volume in 1 s) was 3.8 ± 0.96 l (94.9 ± 13.1% of predicted, normal values [41]). All patients received inhaled ß2-agonist therapy on an as needed basis except for three patients who did not require any medication. In addition, five patients had inhaled corticosteroids and three had inhaled cromoglycate. Both were withheld at least 10 days prior to entry into the study. All patients gave their written informed consent. The study protocol was approved by the local Ethics Committee. Prior to the segmental allergen provocation, patients underwent an inhaled allergen challenge as previously described [29, 42] to establish dual bronchial reactions to the inhaled allergen and to determine the individual PD20FEV1 for the respective allergen.