Nebulized Mycobacterium vaccae protects against asthma by attenuating the imbalance of IRF4/IRF8 expression in dendritic cells  

作　　者：Qi-Xiang Sun Si-Yue Xu Lao-Dong Li Huan Xiao Qian-Nan Zhang Chao-Qian Li 

机构地区：[1]Department of Respiratory Medicine,The First Affiliated Hospital of Guangxi Medical University,Nanning,China

出　　处：《Asian Pacific Journal of Tropical Biomedicine》2022年第12期520-529,共10页亚太热带生物医学杂志（英文版）

基　　金：supported by the National Natural Science Foundation of China under grants(No.81470230);the Natural Science Foundation of Guangxi Zhuang Autonomous Region under grants(No.2020GXNSFDA238003).

摘　　要：Objective:To assess the effects of nebulized inhaled Mycobacterium vaccae on allergic airway inflammation,airway hyperresponsiveness,and Th1/Th2 cell imbalance in mice with ovalbumin(OVA)-induced asthma.Methods:Mice received OVA sensitization and challenge for establishment of the asthmatic model.For intervention,mice received Mycobacterium vaccae nebulization once every other day from the first day of sensitization to the day before challenge.After challenge,pulmonary histological analysis and airway responsiveness measurement were performed.In addition,Th1/Th2 cytokines and OVA-specific IgE levels in bronchoalveolar lavage fluid were measured by ELISA.Th1/Th2 subset ratios and the expression of interferon-regulatory factor 4(IRF4),IRF8 and Toll-like receptor 4(TLR4)in dendritic cells were evaluated by flow cytometry.Results:Severe inflammatory infiltration and airway hyperresponsiveness were observed in OVA-induced asthmatic mice.Asthmatic mice showed higher Th2 cytokine concentration and increased percentage of Th2 cells,along with lower Th1 cytokine concentration and reduced percentage of Th1 cells compared with the normal control.Moreover,an imbalance of IRF4^(+)and IRF8^(+)in dendritic cells was found in asthmatic mice.Nebulized inhaled Mycobacterium vaccae reduced airway hyperresponsiveness and inflammation in OVA-induced asthmatic mice.In addition,nebulized inhaled Mycobacterium vaccae enhanced TLR4 and IRF8 expression,and alleviated the imbalance of Th1/Th2 as well as IRF4^(+)and IRF8^(+)in dendritic cells.Conclusions:Nebulized inhaled Mycobacterium vaccae protects against asthma by alleviating the imbalance of Th1/Th2 and IRF4/IRF8 in OVA-induced asthmatic mice.

关 键 词：Mycobacterium vaccae ASTHMA NEBULIZATION IRF4 IRF8 TLR4 

分 类 号：R562.25[医药卫生—呼吸系统]