白细胞介素12重组腺病毒气道内应用对哮喘豚鼠治疗作用的研究

Effect of intratracheally administered IL-12 recombinant adenovirus on ovalbumin induced bronchial hyresponsiveness in mouse model

目的 探讨激发前气道内应用白细胞介素 12 (IL 12 )重组腺病毒对过敏性气道高反应的调节作用。方法 以C5 7BL/ 6小鼠经鸡卵蛋白 (OVA)免疫建立哮喘模型 ,实验分 6组 ,每组 6只。激发前气管内单次使用IL 12重组腺病毒 (10 8pfu/mouse) ,观察抗原激发后反应的变化。结果 (1)小鼠气道内应用IL 12重组腺病毒在肺内可有效表达 ,48h血浆及肺泡灌洗液IL 12分别为 (5 40± 6 0 )U/ml和 (470 0± 80 0 )U/ml,对照病毒和PBS组未检出 ,两组比较差异有显著性 (P <0 0 1)。 (2 )在抗原激发阶段使用IL 12重组腺病毒 ,可明显抑制肺内IL 4[(3 5± 2 0 )ng/ml∶85 0± 2 5 0 )ng/ml]和IL 5[(6 5± 4 5 )ng/ml∶(5 4 0± 14 0 )ng/ml];γ干扰素 (IFN γ)的产生增加 [(6 90 0± 32 0 )ng/ml∶(12 5±3 2 )ng/ml];并明显抑制气道高反应性 [(36 0± 30 )cmH2 O∶(810± 5 0 )cmH2 O];抑制外周血 [(0 7±0 1) %∶(9 2± 0 5 ) % ]及肺泡灌洗液 [(3 5± 0 7)∶(2 1 6± 4 7)× 10 4 /ml]中的嗜酸细胞的水平 ;与对照组比较 (t分别 =7 97、7 92、5 1 6、18 9、9 33、47 1,P均 <0 0 1) ;但与总IgE[(6 5± 9) μg/ml∶(6 7± 10 )μg/ml]及抗原特异性IgE[(32± 8)∶(33± 8)U/ml]比较无明显影响 (P均 >0 0 5 )。

Objective To assess the effect of intratracheally administered IL 12 recombinant adenovirus (Adm IL 12) on ovalbumin(OVA) induced bronchial hyperresponsiveness in mouse model. Methods C57BL/6 mice were sensitized by ovalbumin. Adm IL 12 with the dose of 10 8pfu/mouse was administered intratracheally before OVA challenge. IL 4,IL 5 and IFN gamma in BALF,bronchial responsiveness,eosinophil count in peripheral blood and BALF,serum total IgE and specific IgE were measured. Results There was IL 12 gene expression in the lung tissue after Adm IL 12 administration, concentration of IL 12 in sera and BALF were (540±60) U/ml and (4 700±800) U/ml respectively,but were unable to be detected in control group ( P <0 01). Compared with the control group,there were significantly lower levels of IL 4[(3 5±2 0) ng/ml vs (85.0± 25.0) ng/ml ]( t =27 97, P <0 01) and IL 5[(6 5±4 5) ng/ml vs (54.0±14.0) ng/ml],( t =7 92, P <0 01) in BALF,accompanying with a higher level of IFN gamma [(690.0±32.0) ng/ml vs (12 5±3 2) ng/ml] ( t =51 6, P <0 01),lower airway resistance [(360±30) cm H 2O vs (810 ±50)cm H 2O]( t =18 9, P <0 01) and lower eosinophil counts in both peripheral blood [(0 7± 0 1)% vs (9 2 ±0 5)%] ( t =47 1, P <0 01) and in BALF [(3 5±0 7)×10 4/ml vs (21 6 ±4 7)×10 4 /ml)] ( t =9 33, P <0 01) However,neither serum total IgE [(65±9) μg/ml vs (67±10) μg/ml],nor specific IgE [(32±8) μg/ml vs (33±8) μg/ml] showed significant difference (all P >0 05). Conclusions Intratracheally administered Adm IL 12 inhibits ovalbumin induced airway hyperresponsiveness ,which may be an effective approach in the management of antigen induced bronchial asthma