结核分枝杆菌重组Ag85A蛋白抗原诱发豚鼠迟发型超敏反应的研究

DTH REACTION OF GUINEA PIG INDUCED BY RECOMBINANT ANTIGEN AG85A OF M.TUBERCULOSIS

目的 :结核分枝杆菌重组Ag85A抗原诱发豚鼠迟发型超敏 (DTH)反应。Ag85A剂量、观察时间对DTH的影响。方法 :常规皮肤实验法 :灭活H37Rv全菌体致敏豚鼠 ,皮肤试验以生理盐水为阴性对照 ,5IUPPD标准品为阳性对照 ,0 .1、0 .2、0 .4、0 .6、0 .8及 1.0 μg重组抗原分别于背部皮内注射 ,注射后 2 4、4 8及 72h分别测量红肿或硬结反应横、纵直径 (mm) ,取两者的平均值。皮肤试验轮圈法 :生理盐水、5IUPPD及 0 .4、0 .6、0 .8、1.0 μgAg85A抗原 ,以轮圈法注射于同一只豚鼠背部一侧 ,每批 6只 ,共 3批。于注射后 2 4、4 8、72h分别测量红肿或硬结反应横、纵直径 (mm) ,取两者的平均值。结果 :常规皮肤试验 0 .1、0 .2 μg重组Ag85A抗原诱发DTH的平均直径与PPD相比有显著差异 (P <0 .0 5 ) ,而 0 .4、0 .6、0 .8、1.0重组Ag85A抗原诱发豚鼠DTH的平均直径与PPD相比 ,无显著差异 (P >0 .0 5 ) ,2 4h平均直径显著高于 4 8h平均直径 (P <0 .0 5 ) ,2 4h测量效果较好。轮圈法皮肤试验排除个体差异后结果与常规皮肤试验结果一致。结论

Objective:To observe the DTH reaction induced by recombinant antigen of M.tuberculosis,Ag85A and the effect of injection dose?observing time on DTH.Methods:Normal skin test: The guinea pig were sensitived by all body of dead H37R.We used normal saline as negative conrtol,5IU PPD as positive control.0.1μg,0.2μg, 0.4 μg, 0.6 μg,0.8μg,1.0μg recombinant antigen of Ag85A were injected into guinea pigs' back respectively. The results were observed 24h,48h,72h after injection.Alternative skin test:normal saline,5IU PPD,0.4μg, 0.6μg , 0.8 μg,1.0μg Ag85A were injected into the back of the same guinea pig.The results were obseved 24h,48h,72h respectively after injection.Results:Normal skin test showed:the DTH reaction of guinea pig induced by 0.1μg/0.2μg were lower than the DTH rection induced by PPD( P <0.05);the DTH reaction of guinea pig induced by 0.4μg, 0.6 μg,0.8μg,1.0ug recombinant Ag85A respectively were not different from the DTH reaction induced by PPD( P >0.05);24h after injection was the best observing time of the test.The results of alternative skin test were coincidence with normal skin test.Conclusions:From the results of our experiments, Ag85A can be taken as a substitute for PPD.