黄芪在树突状细胞水平对哮喘TH 1/TH 2平衡的调节作用

目的 探讨黄芪在树突状细胞(DC)水平对过敏性哮喘TH/TH2平衡的调节作用.方法 用rhGM-CSF和rhIL-4诱导培养外周血来源的DC并予鉴定,ELISA法检测其分泌的细胞因子IL-12、IL-10以及与自身T细胞反应后,RT-PCR检测T-bet和GATA-3 mRNA含量,流式细胞术检测T细胞分泌的胞内细胞因子IL-4和IFN-γ水平.结果 哮喘患儿外周血DC分泌IL-10高于对照组(P＜0.05);黄芪干预后DC分泌IL-10降低,与哮喘组比较差异有统计学意义(P＜0.05).哮喘患儿外周血DC分泌IL-12低于对照组(P＜0.05);黄芪干预后DC分泌IL-12增加,但与哮喘组比较差异无统计学意义.混合培养第7天哮喘组T细胞内IL-4水平显著高于正常对照组(P＜0.01);而IFN-γ水平则显著低于正常对照组(P＜0.05);哮喘组IL-4/IFN-γ比值高于正常对照组(P＜0.01).黄芪干预后T细胞内IL-4水平与哮喘组比较差异无统计学意义,而IFN-γ水平增加,与哮喘组比较差异有统计学意义(P＜0.05),IL-4/IFN-γ比值降低,与哮喘组比较差异有统计学意义(P＜0.01).哮喘组T-bet mRNA的表达强度明显低于正常对照组(P＜0.01);而哮喘组GATA-3 mRNA的表达强度则明显高于正常对照组(P＜0.05);哮喘组GATA-3/T-bet比值高于正常对照组(P＜0.05).黄芪干预后T细胞GATA-3 mRNA的表达强度与哮喘组比较差异无统计学意义,而T-bet mRNA水平增加,与哮喘组比较差异有统计学意义(P＜0.05),GATA-3/T-bet比值降低,与哮喘组比较差异有统计学意义(P＜0.01).结论 哮喘患儿DC功能缺陷,产生IL-12减少、IL-10增加导致TH2优势分化,从而使TH1/TH2平衡向TH2倾斜,合成IFN-γ减少,进而造成气道慢性炎症、气道高反应性而致哮喘发作.黄芪对DC的调节主要通过降低IL-10的分泌水平,从而降低其抑制TH0细胞向TH 1分化的功能,即间接抑制了TH0细胞向TH2的分化.

The role of Huang-qi in balance of THl/TH2 in asthma on dendritic cells level

Objective To investigate the role of Huang-qi in balance of TH1/TH2 in asthma on dendritic cells level. Methods DCs from human peripheral blood mononuclear cells(PBMC) were induced by rhGM-CSF and rhIL-4, and then were identified. The level of IL-12 and IL-10 produced by DCs were de-tected by ELISA assay. After autoreactive T cells, mRNA of T-bet and GATA-3 was measured by RT-PCR. Simultaneously, IL-4 and IFN-γ were determined by flow cytometer. Results After 7 days culture, IL-12 was significantly decreased in asthma group compared to control group (P ＜ 0.01), whereas IL-10 on the opposite. At the 7th day of co-culture with T cells derived from floating cells, the IFN-γ/and T-bet mRNA level in asthma group were significantly decreased than that in control group, whereas IL-4, GATA-3 mRNA level, the ratio of IL-4/IFN-γ and GATA-3/T-bet were apparently increased in asthma group than that in control group(P＜0.01). After Huang-qi treatment, the IFN-γ/and T-bet mRNA level were significantly in-creased, whereas the ratio of IL-4/IFN-γ and GATA-3/T-bet, and the IL-10 level were apparently de-creased, but the level of IL-12, IL-4 and GATA-3 mRNA were not changed significantly. Conclusion DCs in asthma regulated the balance of TH1/TH2 by means of secreting decreased IL-12 and increased IL-10, that made TH2 playing a dominance role which is the key factor in initiating asthma. Huang-qi regulated DCs through decreasing the level of IL-10, and thus decreased the ability of inhibiting the differentiation of TH1 from TH0, that is also inhibiting the differentiation of TH2 from TH0 directly.