The aim of this study was to evaluate the changes in the three subsets of monocyte (classical, intermediate, and non-classical) and the expression of human leukocyte antigen-DR (HLA-DR) on monocyte subsets during MP pneumonia in children. Monocyte subsets were analyzed in the peripheral blood of healthy volunteers and MP pneumonia patients at the stages of admission and remission after clinical therapy. They were defined as classical (CD14+CD16-), intermediate (CD14brightCD16+), and non-classical (CD14dimCD16+) using flow cytometry. Furthermore, three subsets of monocyte were analyzed for the expression of HLA-DR. Patients with MP pneumonia at admission had a higher proportion of intermediate and non-classical monocytes than healthy subjects (all P < 0.05). The proportion of intermediate subset and non-classical subset was lower in MP pneumonia patients at remission than at admission (all P < 0.05). In comparison with the other monocyte subsets, intermediate subset showed a significantly higher percentage of HLA-DR in MP pneumonia patients at admission (P < 0.05). Further analysis revealed that the expression of HLA-DR on intermediate subset was lower in severe patients than in non-severe patients (P < 0.05).Our data has shown for the first time that MP pneumonia is associated with the increased proportion of non-classical and intermediate monocytes, indicating the involvement of monocyte-related mechanisms in the pathogenesis of this disease. Additionally, the decreased expression of HLA-DR on CD14brightCD16+ subset may be a potential indicator of the severity of MP pneumonia.

中文翻译：

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儿童肺炎支原体肺炎的单核细胞亚群研究。

这项研究的目的是评估儿童MP肺炎期间单核细胞的三个子集（经典，中间和非经典）的变化以及人类白细胞抗原-DR（HLA-DR）在单核细胞子集上的表达。在临床治疗后，在健康志愿者和MP肺炎患者入院和缓解阶段对外周血单核细胞亚群进行分析。使用流式细胞仪将它们定义为经典（CD14 + CD16-），中间（CD14brightCD16 +）和非经典（CD14dimCD16 +）。此外，分析了单核细胞的三个子集的HLA-DR表达。入院时MP肺炎患者的中级和非经典单核细胞比例高于健康受试者（所有P <0.05）。MP肺炎患者缓解后的中间亚组和非经典亚组的比例低于入院时（所有P <0.05）。与其他单核细胞亚群相比，中间亚群显示MP肺炎患者入院时HLA-DR的百分比显着更高（P <0.05）。进一步的分析表明，重症患者中HLA-DR的表达低于重症患者（P <0.05）。我们的数据首次显示MP肺炎与非重症患者肺炎的比例增加有关经典的和中间的单核细胞，表明单核细胞相关机制参与了该病的发病机理。此外，HLA-DR在CD14brightCD16 +子集上的表达降低可能是MP肺炎严重程度的潜在指标。