支原体肺炎患儿急性期外周血辅助性T淋巴细胞亚群的功能变化

Variations of the functions of T helper lymphocyte subsets in peripheral blood of children with mycoplasma pneumoniae pneumonia in acute phase

目的观察支原体肺炎(MPP)患儿急性期外周血辅助性T淋巴细胞(Th)亚群的功能变化,以探讨其在MPP发病机制中的意义。方法对40例MPP患儿外周血单个核细胞(PBMC)经佛波酯+Ca2+导入剂体外诱导48 h,ELISA法检测上清液中IL-4、IFN-γ、转化生长因子-β1(TGF-β1)水平。结果MPP患儿急性期IFN-γ水平、IFN-γ/IL-4比值显著低于对照组(P<0.01),IL-4、TGF-β1水平显著高于对照组(P<0.01);PBMC培养上清液的TGF-β1水平与IFN-γI、L-4的水平呈正相关(P<0.01),而与IFN-γ/IL-4比值呈负相关(P<0.05);MPP患儿急性期并发肺外损害组PBMC培养上清液中TGF-β1I、L-4、IFN-γ水平及IFN-γ/IL-4比值与无肺外损害组差异均无统计学意义(P>0.05)。结论MPP患儿急性期Th1/Th2失衡,呈现Th2相对优势状态;体内出现保护性或调节性Th3功能增强,但TGF-β1保护性调节不足,使Th1/Th2失衡不能纠正;MPP患儿急性期Th细胞亚群功能变化与其急性期有无肺外损害无关。

Objective To observe the variations of the functional states of T helper cells（Th） in peripheral blood of children with mycoplasma pneumoniae pneumonia（MPP） in acute phase, and to explore their roles in the pathogenesis of MPP. Methods Peripheral blood mononuclear cells（PBMC） of 40 MPP children were stimulated with PMA and ionomycin and cultured in vitro for 48 hours. The levels of IL-4, IFN-γ, and TGF-β1 in the supernatants of PBMC were detected by ELISA. Results The levels of IFN-γ and the ratio of IFN-γ/IL-4 of MPP children in acute phase were significantly lower than those of the controls（P 〈 0.01 ）;The levels of IL-4 and TGF-β1 were markedly higher than those of the controls（ P 〈 0.01 ） ; The levels of TGF-β1 in the supernatants of PBMC were positively correlated with the levels of IFN-γ and IL-4（ P 〈 0.01 ）,but negatively correlated with the ratio of IFN-γ/IL-4（P 〈0.05）. The supernatants levels of TGF-β1, IL-4, IFN-γ and the ratio of IFN-γ/IL-4 of MPP children in acute phase had no difference between the patients with the extrapulmonary damage and those without（P 〉 0.05）. Conclusions The function of Th2 relatively prevails over Th1 in MPP children. The protective or regulative function of Th3 in vivo increases,but the protective regulation of TGF-β1 is insufficient,so the imbalance of Th1/ Th2 can not be corrected. The variation of the functional states of T helper cells in acute phase has no relationship with or without the extrapulmonary damage.