维生素A制剂对支气管哮喘患儿外周血辅助性T淋巴细胞17和调节性T淋巴细胞功能的影响

Influence of different doses of vitamin A supplements on the function of T help 17 and regulatory T cells in peripheral blood of asthmatic children

目的观察维生素A（VitA）制剂对支气管哮喘（哮喘）患儿外周血辅助性T淋巴细胞17（Thl7）和调节性T淋巴细胞（Treg）功能的影响，探讨VitA的免疫调节机制。方法选择20例哮喘发作期患儿为研究对象（哮喘组），16例健康儿童为健康对照组。2组均在无菌条件下采用密度梯度离心法获取外周血单个核细胞（PBMC）悬液，哮喘组置于不同浓度VitA制剂[0．0μmol／L（空白对照）、0．5μmol／L、1．0μmol／L、2．0μmol／L]条件下，健康对照组无VitA制剂干预，培养72h后留取上清液，酶联免疫吸附法测定上清中IL-17、IL-10和转化生长因子131（TGF-p1）水平的变化。结果1．哮喘组PBMC分泌IL-17水平显著高于健康对照组[（960．534-75．59）ng／L比（425．07±70．71）ng／L，P〈0．01]，而IL-10和TGF-[31水平均显著低于健康对照组[（53．13±6．94）rig／L比（84．41±6．02）ng／L，（304．51±51．52）ng／L比（489．45±73．68）ng／L，P均〈0．01]。2．哮喘儿童PBMC在VitA制剂浓度为0．5μmol／L、1．0Ixmo]／L及2．0μmol／L水平时，IL-17分泌水平[（588．954-44．18）ng／L、（573．13±27．43）ng／L、（686．71±38．98）ng／L]均显著低于空白对照组[（960．53±75．59）ng／L，P均〈0．01]，浓度为2．0μmol／L组显著高于0．5μmol／L组和1．0μmol／L组（P均〈0．01）。3．哮喘儿童PBMc在VitA制剂浓度为0．5μmol／L、1．0μmo]／L及2．0μmol／L水平时，IL-10分泌水平[（105．35±10．79）ng／L、（111．21±16．11）ng/L、（81．09±6．05）ng／L]显著高于空白对照组[（53．13±6．94）rig／L，P均〈0．01]，TGF-131分泌水平[（933．01±73．98）ng／L、（1223．31±105．99）ng／L、（776．98±145．44）ng／L]亦显著高于空白对照组[（304．51±51．52）ng／L，P均〈0．01]，0．5μmol／L组和1．0μmol／L组显著高于2．0μmol／L组，差异均有统计学意义（P均〈0．01）；1．0μmol／L组TGF-131水平显著高于0．5μmol／L组（P〈0．01）。结论哮喘儿发作期Thl7功能增强，而Treg细胞功能降低，Thl7／Treg细胞功能平衡紊乱；VitA制剂能降低哮喘患儿外周血Thl7功能，增强Treg细胞活性。生理水平的VitA制剂此作用最佳，高浓度时作用明显减弱。

Objective To observe the effect of vitamin A（VitA） on T help 17 （Th17） and regulatory T cells （Treg） in the peripheral blood in children with asthma and their dose effect relationship, and to investigate the immuno- regulation mechanism of VitA. Methods Twenty children with asthma （asthma group ） and 16 healthy children （healthy control group） were selected. Peripheral blood mononuclear cells （PBMC） were isolated from venous blood by density gradient centrifugation in the aseptic condition. Different concentrations of VitA [ 0.0 μmol/L （blank control） , 0.5 μmol/L,1.0 μmol/L,2.0 μmol/L] were added into the cultures in the asthma group. The healthy control group were not interfered with VitA. The supematant was collected after 72 h. The levels of interlenkin 17 （ IL - 17） ,interlen- kin 10（ IL - 10 ） and transforming growth factor - β1 （TGF -β1 ） in the supernatant were determined by enzyme - linked immunosorbent assay. Results （ 1 ） IL - 17 levels produced by PBMC in the asthma group were significantly higher than those in the healthy control group[ （960.53 ± 75.59） ng/L vs （425.07 ± 70.71 ） ng/L, P 〈 0.01 ], and the levels of IL - 10 and TGF - β1 were significantly lower than those in the healthy control group[ （53.13 ± 6.94） ng/L vs （84.41 ±6.02） ng/L, （304.51 ±51.52） ng/L vs （489.45 ± 73.68） ng/L,all P 〈0.011- （2） IL - 17 levels produced by PBMC in the 0.5 μmol/L, 1.0 μmol/L and 2.0 μmol/L VitA concentration of the asthma group [ （ 588.95± 44.18 ） ng/L, （573.13 ± 27.43 ） ng/L, （ 686.71 ±38.98 ） ng/L, were significantly lower than those in the blank control group[ （960.53±75.59） ng/L, all P 〈0.01 ] ,and IL - 17 levels in the 2.0 μmol/L VitA concen- tration were significantly higher than those in 0.5 μmol/L and 1.0 μmol/L concentration group （P 〈0.01 ）. （3）IL - 10 levels produced by PBMC in the 0.5 μmol/L, 1.0 μmol/L and 2.0 μmol/L VitA concentration of the asthma group [ （ 105.35 ± 10.79 ） ng/L, （ 111.21 ± 16.11 ） ng/L, （ 81.09 ±6.05 ） ng/L] were significantly higher than those in the blank control group[ （53.13 ±6.94） ng/L, all P 〈0.011 , TGF - 131 levels produced by PBMC in the 0.5 μmol/L, 1.0 μmol/L and 2.0 Ixmol/L VitA concentration of the asthma group[ （933.01 ± 73.98 ） ng/L, （ 1 223.31 ± 105.99 ） ng/L, （776.98± 145.44） ng/L, were significantly higher than that in blank control group[ （304.51 ±51.52） ng/L,all P 〈0.01 ] ,and the levels of IL - 10 and TGF - 131 in the 0.5 μmol/L and 1.0 μmol/L concentration group were significantly higher than those in the 2.0 μmol/L concentration group（ all P 〈 0.01 ）. The level of TGF - 131 in the 1.0 txmol/L concentration group were significantly higher than that in the 0.5 μmol,/L concentration group （ P 〈 0.01 ）. Conclusions The function of Thl7 in children with asthma during asthma attack was enhanced,and the func- tion of Treg cells was reduced. The balance disorder of the functions of Thl7 and Treg ceils occurred. VitA can reduce the function of Thl7 in peripheral blood, and enhance the activity of Treg cells in the children with asthma. The physio- logical level of VitA has the best effect, if high VitA concentration is high its effect is significantly decreased.