新生期卡介苗接种对实验性哮喘小鼠肺Th17细胞和IL-17的影响

目的：通过实验性哮喘小鼠模型探讨新生期卡介苗（bacillus Calmette-Guérin,BCG）接种对肺Th17细胞和IL-17的影响。方法：新生期小鼠分3组：对照组，卵白蛋白组（OVA），BCG干预组（BCG/OVA）。除对照组外，其余两组均给予OVA致敏和激发。观察支气管肺泡灌洗液（bronchoalveolar lavage fluid,BALF）中细胞总数及分类，ELISA法检测BALF中IFN-γ、IL-17含量，流式细胞术检测肺Th17细胞。结果：两哮喘组BALF中细胞总数、淋巴细胞、嗜酸性粒细胞、中性粒细胞比例均明显高于对照组，而BCG/OVA组上述细胞均显著低于OVA组。两哮喘组BALF中IFN-γ水平明显低于对照组，IL-17显著高于对照组，同时BCG/OVA组IL-17水平明显低于OVA组。流式细胞术显示，两哮喘组Th17细胞比例均明显高于对照组，但两哮喘组间差异无统计学意义。结论：Th17细胞/IL-17在实验性哮喘小鼠发病中起作用，新生期BCG接种可抑制气道IL-17的产生，其抑制的IL-17可能并非主要由Th17细胞产生，而来源于其他细胞。［中国当代儿科杂志，2010，12（8）：650-653］

Impact of neonatal bacillus Calmette-Guerin vaccination on lung Th17 cells and IL-17 in murine asthma model

Objective To study the impact of neonatal bacillus Calmette-Guerin(BCG)vaccination on lung Th17 cells and IL-17 in murine asthma model.Methods Neonatal BALB/c mice were divided into three groups:control,OVA and BCG/OVA groups.BCG was administerd in the BCG/OVA group on postnatal day 2 or 3.Except the control group,the mice in the other two groups were sensitized and undergone OVA challenge.Inflammatory cell numbers and morphological identification of leucocytes in bronchoalveolar lavage fluid(BALF)were measured by light microscopy.Cytokine IFN-γ and IL-17 levels in BALF were measured using ELISA.The percentage of lung Th17 cells were assayed by flow cytometry.Results There was significantly larger number of total cells,lymphocytes,eosinophils and neutrophils in BALF in the OVA and BCG/OVA groups compared with the control group.The number or percentage of those cells in the BCG/OVA group was lower than that in the OVA group.The level of IL-17 in BALF was significantly higher in the OVA and the BCG/OVA groups compared with the control group,while the level of IFN-γ was lower.The OVA group had higher level of IL-17 than the BCG/OVA group.The mice in the OVA and the BCG/OVA groups had a higher percentage of Th17 cells in lungs compared with the control group,but there were no significant differences in the percentage of Th17 cells between the OVA and the BCG/OVA groups.Conclusions Th17 cells and IL-17 play roles in the pathogenesis of asthma.BCG vaccination can reduce the level of IL-17 in BALF and the reduced IL-17 may be mainly from other IL-17-producing cells in the lungs,not Th17 cells.