Journal of Capital Medical University ›› 2023, Vol. 44 ›› Issue (2): 212-220.doi: 10.3969/j.issn.1006-7795.2023.02.005

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Streptococcus pneumoniae infection at early stage of life affect the severity of asthma induced by exposure to the same bacterial antigens in adulthood

Peng Dan1,2, Pang Jie1, Shi Yifan1, Cui Lele1, Xu Yingjie1, Li Yan3, Cui Ye1, Chen Yan1, Yuan Huihui1, Qin Xiaofeng1, Lyu Zhe1,  Wang Wei1, Sun Ying1*   

  1. 1. Department of Immunology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China; 2. Laboratory of Allergy and Precision Medicine, the Third People's Hospital of Chengdu, Chengdu 610014, China; 3. Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing  100730, China
  • Received:2023-01-24 Online:2023-04-21 Published:2023-04-17
  • Supported by:
    This study was supported by National Natural Science Foundation of China (82071805, 82090013,81971510, 81770049), the Beijing Municipal High Level of Teacher Team Construction in Colleges and Universities Support Plan High Level Innovation Teams Construction Projects (IDHT20190510).

Abstract: Objective  To investigate the influence and mechanisms of infection with Streptococcus pneumoniae(SP)at early stage of life and late exposure to the same bacterial antigens on the occurrence and development of asthma.Methods  Mice (one week old of BALB/c background) were infected with SP, then 5 weeks later challenged intranasally with inactivate SP bacteria and interleukin-33 (IL-33)+inactivated SP bacteria to establish model. Lung function and airways hyperresponsiveness (AHR), total cellular and differential counts in bronchoalveolar lavage fluid (BALF) and lungs were measured to evaluate the inflammatory cell infiltration and inflammatory changes in the airways/lungs.The expression levels of IgE and SP specific IgE and IgG in serum, as well as the expression levels of various cytokines in lung homogenates were detected with ELISA.The number of T helper cell (Th) subgroup (Th1, Th2, Th17) and innate lymphoid cells (ILC1, ILC2, ILC3) were measure with flow cytometry. Results  Early-life airways infection with SP and repeated exposure to the same bacterial antigen alone in adulthood failed to induce asthma-like pathological changes. In the presence of IL-33, early-life airways infection with SP and repeated exposure to the same bacterial antigen attenuated asthma-like pathological changes, including the dereased AHR, inflammatory cellular infiltration of the airways,  secretion of mucus and smooth muscle hyperplasia in lung tissue, serum concentrations of IgE and  concentrations of Th2-type cytokines,  numbers of activated Th1, Th2, Th17 and ILC1 cells in the lung tissues, but an increased IL-10 expression, compared with those mice without SP infection in early life. Conclusion  Early-life airways infection with SP attenuted the severity of asthma induced by exposure to the same bacterial antigens in adulthood.

Key words: early birth infections, Streptococcus pneumoniae, interleukin-33 (IL-33), bacterial antigens, asthma

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