Th9细胞与IL-9在肺炎支原体感染患儿中的检测及其临床意义

目的 探讨辅助性T 细胞9(Th9)及其细胞因子白细胞介素-9(IL-9)在肺炎支原体(MP)感染患儿中的临床意义。方法 2013 年1 月至2014 年6 月诊断为MP 感染患儿86 例,分为上呼吸道感染组(URI 组,n=29)、轻症MP 肺炎(MPP)组(n=32)和重症MPP 组(n=25)。另选取28 例同期行健康体检儿童为对照组。Ficoll 密度梯度离心法分离外周血单个核细胞,采用流式细胞术检测各组外周血Th9 细胞百分率;ELISA 法检测各组血清细胞因子IL-9 水平。结果 URI 组、轻症MPP 组和重症MPP 组患儿外周血Th9 细胞百分率及IL-9 水平均高于对照组(P<0.05);轻症MPP 组和重症MPP 组患儿外周血Th9 细胞百分率及IL-9 水平均高于URI 组(P<0.05),且重症MPP 组显著高于轻症MPP 组(P<0.01)。结论 MP 感染患儿外周血Th9 细胞百分率及其细胞因子IL-9 的表达水平升高,且随病情加重而增加,推测Th9 细胞及IL-9 可作为MP 感染患儿病情发展及转归的评价指标。

Determination of Th9 cells and IL-9 in children with Mycoplasma pneumoniae infection

Objective To investigate the clinical significance of T helper type 9 (Th9) cells and interleukin-9 (IL- 9) in children suffering from Mycoplasma pneumoniae (MP) infection. Methods A total of 86 children who were diagnosed with MP infection between January 2013 and June 2014 were classified into upper respiratory infection (URI) group (n=29), mild MP pneumonia (MPP) group (n=32) and severe MPP group (n=25). Twenty-eight healthy children were used as the control group. Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and the percentage of Th9 cells in peripheral blood was measured by flow cytometry. Serum IL-9 level was determined using ELISA. Results The URI, mild MPP, and severe MPP groups had significantly higher percentages of Th9 cells and IL-9 levels than the control group (P<0.05); the mild MPP and severe MPP groups had significantly higher percentages of Th9 cells and IL-9 levels than the URI group (P<0.05), and the two indices were significantly higher in the severe MPP group than in the mild MPP group (P<0.01). Conclusions Children with MP infection have an elevated percentage of Th9 cells and IL-9 expression, both of which are positively correlated with the severity of the disease. It can be predicted that Th9 cells and IL-9 can be used as evaluation indicators for the progression and outcome of children with MP infection.