不同活菌数卡介苗制品诱导免疫反应差异的比较

Comparative study on the differences of immune response induced by BCG vaccines containing different numbers of viable bacteria

目的比较不同活菌数卡介苗(BacilleCalmette-Guérin,BCG)制品诱导的免疫反应的差异。方法用不同活菌数BCG分别免疫豚鼠和小鼠后,采用BCG纯蛋白衍生物(purified protein derivative,PPD)试验检测豚鼠免疫后诱导的变态反应大小,酶联免疫斑点法(enzyme-linked immunospot assay,ELISPOT)检测小鼠脾淋巴细胞分泌抗原特异性IFNγ的水平,分析不同评价方法的检测结果与BCG活菌数的相关性。结果在活菌数(1.5~4.6)×10^(6)CFU/mg范围内,PPD反应大小与BCG的活菌数无相关性,而抗原特异性的IFNγ分泌水平与活菌数呈正相关。结论相较于传统的PPD试验,ELISPOT法能更精确地评价BCG的效力与BCG活菌数之间的量效关系。

Objective To compare immune responses induced by BCG vaccines containing different numbers of viable bacteria. Methods Guinea pigs and mice were immunized with BCG vaccines with different viable bacteria counts.Allergic reaction levels in immunized guinea pigs were examined with BCG purified protein derivative(PPD)tests. Levels of antigen-specific IFNγ secreted from murine spleen lymphocytes were detected with enzyme-linked immunospot assay(ELISPOT). The correlation between results from different evaluation methods and the number of viable bacteria in BCG vaccines was also analyzed. Results Within the range of(1. 5 ~ 4. 6)× 10^(6)CFU/mg of the number of viable bacteria in BCG vaccines,no correlation between PPD reaction levels and viable bacteria counts could be detected,while the secretion of antigen-specific IFNγ is positively correlated with the number of viable bacteria. Conclusion Compared to traditional PPD test,ELISPOT is more accurate when evaluating the dose-dependent-effect between the efficacy and the viable counts of BCG vaccines.