Background

Mycoplasma pneumoniae is a major pathogen for community-acquired pneumonia and frequently causes outbreaks in children. M. pneumoniae-specific antibody response is detected upon acute infection and the serology is widely used in the clinical setting. Nevertheless, the cellular basis for antigen-specific antibody response to acute M. pneumoniae infection is largely undetermined in children.

Methods

Hospitalized children with community-acquired pneumonia were enrolled and the infection with M. pneumoniae was confirmed with positive PCR result and negative findings for other pathogens. The M. pneumoniae P1-specific antibody-secreting B cell (ASC) response was examined with the ex vivo enzyme-linked immunosorbent spot assay and the relationships between the ASC frequency and serological level and clinical parameters within M. pneumoniae patients were studied.

Results

A robust M. pneumoniae P1-specific ASC response was detected in the peripheral blood among M. pneumoniae-positive patients. By contrast, no M. pneumoniae-specific ASCs were detected among M. pneumoniae-negative patients. The IgM-secreting B cells are the predominant class and account for over 60% of total circulating M. pneumoniae-specific ASCs in the acute phase of illness. The M. pneumoniae P1-specific ASC frequency significantly correlated with the fever duration, and the IgG ASC frequency significantly correlated with serological titer among patients.

Conclusion

A rapid and potent elicitation of peripheral M. pneumoniae-specific ASC response to acute infection provides the cellular basis of antigen-specific humoral response and indicates the potential of cell-based diagnostic tool for acute M. pneumoniae infection. Our findings warrant further investigations into functional and molecular aspects of antibody immunity to M. pneumoniae.

中文翻译：

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肺炎儿童对肺炎支原体的有效抗体分泌 B 细胞反应

背景

肺炎支原体是社区获得性肺炎的主要病原体，经常在儿童中引起暴发。在急性感染时检测到肺炎支原体特异性抗体反应，并且血清学广泛用于临床环境中。然而，在儿童中，对急性肺炎支原体感染的抗原特异性抗体反应的细胞基础在很大程度上尚未确定。

方法

入组患有社区获得性肺炎的住院儿童，经 PCR 结果阳性和其他病原体阴性结果证实感染了肺炎支原体。用离体酶联免疫吸附点测定法检查了肺炎支原体e P1 特异性抗体分泌 B 细胞 (ASC) 反应，并研究了肺炎支原体患者中 ASC 频率与血清学水平和临床参数之间的关系。

结果

在肺炎支原体e 阳性患者的外周血中检测到强烈的肺炎支原体e P1 特异性 ASC 反应。相比之下，在肺炎分枝杆菌e 阴性患者中未检测到肺炎分枝杆菌e 特异性 ASC 。分泌 IgM 的 B 细胞是主要类别，占疾病急性期总循环肺炎分枝杆菌e 特异性 ASC 的 60% 以上。肺炎支原体e P1 特异性 ASC 频率与发热持续时间显着相关，IgG ASC 频率与患者的血清学滴度显着相关。

结论

对急性感染的外周肺炎分枝杆菌e 特异性 ASC 反应的快速有效诱导为抗原特异性体液反应提供了细胞基础，并表明基于细胞的诊断工具对急性肺炎分枝杆菌感染的潜力。我们的研究结果值得进一步研究对肺炎支原体的抗体免疫的功能和分子方面。