ABSTRACT
BACKGROUND/AIM: Bronchiolitis is a common acute lower respiratory tract infectious disease in infants. Respiratory syncytial virus (RSV) infection is one of the main causes. Bronchiolitis can lead to a significant increase in the incidence of asthma in young children, but the mechanism of bronchiolitis transforming into asthma is still unclear. The study was aimed at investigating the role of NF-κB/IL-33/ST2 axis on RSV-induced acute bronchiolitis. METHODS: A total of 40 infants diagnosed with acute bronchiolitis infected by RSV, and 20 normal infants were included in this study. BALB/c mice (6-8 weeks old, 20 ± 1.1 g) were used as study models. Enzyme-linked immunosorbent assay (ELISA), quantitative real time PCR, western blot analysis, immunohistochemical staining, and flow cytometry analysis were performed to examine relevant indicators. RESULTS: IL-33 level was significantly elevated, and Th1/Th2 ratio is imbalance after in infants with acute bronchiolitis. In vivo study, we found that NF-κB/IL-33/ST2 axis is mediated the Th2 cytokine levels and BAL cell number induced by RSV. Acute bronchiolitis induced by RSV in a mouse model is attenuated after inhibition of NF-κB/IL-33/ST2 pathway. Moreover, we also confirmed that macrophages are important sources of IL-33 and are regulated by NF-κB pathway in RSV-induced mice. CONCLUSION: We confirmed that inhibition of NF-κB/IL-33/ST2 axis could attenuate acute bronchiolitis by RSV infected. Our findings not only demonstrate the potential role of IL-33 antibody in attenuating RSV-induced lung damage but also provide a new insight into better prevention of RSV-induced asthma by mediating NF-κB/IL-33/ST2 axis.
Subject(s)
Bronchiolitis/metabolism , Bronchiolitis/virology , Interleukin-1 Receptor-Like 1 Protein/metabolism , Interleukin-33/metabolism , NF-kappa B/metabolism , Respiratory Syncytial Virus Infections/metabolism , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human , Acute Disease , Animals , Biomarkers , Bronchiolitis/pathology , Bronchoalveolar Lavage Fluid/cytology , Cytokines/metabolism , Disease Models, Animal , Disease Susceptibility , Host-Pathogen Interactions , Humans , Immunohistochemistry , Immunophenotyping , Macrophages/immunology , Macrophages/metabolism , Mice , Respiratory Syncytial Virus Infections/pathology , Respiratory Syncytial Virus, Human/physiology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolismABSTRACT
By analyzing the epidemiological and clinical features of adenovirus in children with acute respiratory tract infection (ARTI), we provide a theoretical basis for early clinical diagnosis and treatment. Nasopharyngeal secretions were collected from 3480 children with ARTI, who were hospitalized at the No. 2 Hospital of Changzhou from January 2011 to December 2012. Adenovirus were detected using direct immunofluorescence assays. A total of 80 samples were positive for adenovirus (2.30%). The rate of adenovirus infection during 2011 was significantly higher than that in 2012, and the infection rate was higher in summer and autumn than in winter and spring. The infection rate was 1.14% among children aged < 1-year-old and the rates were higher among children in other age ranges. Adenovirus was found to be an important ARTI pathogen in children in Changzhou, mainly affecting children older than 1 year. ADV infections have various clinical presentations, but affected children tend to be severely ill with poor outcomes.