【Abstract】 Objective To study the role of house dust mite ( HDM) induced airway epithelium TLR4 expression and T lymphocyte activation in asthmatic inflammation. Methods Thirty BALB/ c mice were randomly divided into an ovalbumin ( OVA) group, a HDMgroup, and a control group. The mice in the OVA group were sensitized with OVA and Al( OH) 3 , and repeatedly exposed to aerosolized OVA. The mice in the HDMgroup and the control group were sensitized and challenged with HDMand saline, respectively.Histopathology changes of pulmonary tissue and airway were observed under light microscope. Levels of IL-4, IL-5, IL-13, IL-17, and IFN-γin BALF were measured by ELISA. Total and differential cell counts in bronchoalveolar lavage fluid ( BALF) were also measured. The mRNA and protein expressions of TLR4 weredetected by quantitative real-time PCR and Western blot, respectively. Th1, Th2, and cells in the peripheral blood were detected by flow cytometry. Results Light microscope revealed eosinophil specific inflammatory cells infiltration around the peribronchovascular region,mucus gland hyperplasia, and airway mucous plug inthe OVA group. The HDM group showed more severe alveolar and intersititial congestion and neutrophils infiltration. The control group showed intact alveolus with few mucous plug and inflammatory cells.Compared with the OVA group, significant increases in the number of total cells and neutrophils, as well as significantly higher expression of IL-4, IL-5, IL-13, and IL-17 were detected in the HDMgroup ( P lt;0. 05) ,while IFN-γexpression had no significant change ( P gt;0. 05) . The expression of TLR4 mRNA and protein significantly increased in the HDMgroup( P lt; 0. 05) , and did not change significantly in the other two groups ( P gt;0. 05) . The percentages of Th2 and Th17 cells in peripheral blood in the HDMgroup were significantly higher than the OVA group ( P lt;0. 05) . Conclusion HDM may induce inflammatory cells infiltration andactivation of Th2 and Th17 lymphocyte cells via up-regulation of TLR4 expression in airway epithelium,which might play an important role in asthmatic inflammation.
Objective To investigate the effects of dust mite allergen Derp1 on the expressions of IL-6 and IL-8 in primary rat bronchial epithelial cells. Methods The primary rat bronchial epithelial cells were divided into a control group and three experimental groups. In the experimental groups, the cells were cultured with 3 different concentrations of Derp1 ( 1, 5, 10 μg/mL) for 3 different time ( 4, 8, 24 h) .Inverted microscope was employed to observe the morphological changes of bronchial epithelial cells and intercellular space, and supernatants were assayed for IL-6 and IL-8 with ELISA. Results Complete flattening of single cells layer was observed in the control group. In the experimental groups, the cells treated with Derp1 allergen showed no obvious changes in the cell morphology and intercellular space. However,There was a significant change in the level of cytokines production compared with the control group. The levels of IL-6 and IL-8 began to rise at 4 h, and reach to high level at 8 h, especially in the 5 and 10 μg/mL groups ( P lt;0. 01) . In the 24h group, the concentrations further increased but not reach statistical difference compared with 8h group ( P gt; 0. 05) . Conclusions The Derp1 allergen can stimulate the release of inflammatory cytokines such as IL-6 and IL-8 fromthe rat trachea- bronchia epithelial cells. It is suggested that dust mite allergen -induced cytokines may play important roles in the pathogenesis of allergic asthma.
ObjectiveTo systematically review the efficacy and safety of dust mite sublingual immunotherapy (SLIT) in the treatment of children with allergic rhinitis. MethodsRandomized controlled trials (RCTs) about SLIT treating allergic rhinitis in pediatric patients was searched in PubMed, EMbase, CBM, Ovid, The Cochrane Library (Issue 5, 2014), CNKI, VIP and WanFang Data from inception to May 2014. Two reviewers independently screened literature according to inclusion and exclusion criteria, extracted data, and assessed methodological quality of included studies. Then meta-analysis was conducted using RevMan 5.3 software. ResultsA total of nine RCTs including 663 patients were finally included. The results of meta-analysis indicated that:the trial group was superior to the control group in reducing the scores of drug use (SMD=-0.61, 95%CI-0.94 to-0.27, P=0.000 4) and mite-specific serum IgE levels (follow-up time > 22 weeks:SMD=0.71, 95%CI 0.31 to 1.12, P=0.000 5). However, no significant difference was found between the two groups in the scores of nasal symptoms (SMD=0.06, 95%CI-0.13 to 0.25, P=0.55) and the incidence of adverse reaction (OR=1.3, 95%CI 0.89 to 1.90, P=0.17). ConclusionSLIT could decrease the use frequency of antihistamine, β-agonist and nasal spray steroids, and it has less adverse reaction and better safety in the treatment of children with allergic rhinitis. But SLIT could neither effectively alleviate nasal symptoms nor reduce mite-specific serum IgE levels of pediatric patients with allergic rhinitis in a short time.