小鼠不同基因型与乙肝疫苗免疫应答的关系研究

The relationship between genotype of mouse and the immune response of hepatitis B vaccine

目的研究实验小鼠基因型与乙肝疫苗免疫应答的关系。以保证根据小鼠基因型选择适于进行免疫应答检测的实验小鼠，保证进行疫苗免疫应答检测时的规范化和标准化。方法应用小鼠NIH1、2、3个种群和BALB／c、DBA／1共3种不同品系和同一品系不同种群的小鼠各40只，乙肝疫苗稀释4个不同的稀释度，每个稀释度注射动物10只。酶标法检测乙肝疫苗免疫效力，测定乙肝疫苗的半数有效剂量（ED50）值，再通过微量细胞毒法和PCR方法检测小鼠的H-2单倍型，计算不同品系小鼠H-2^q的百分比，得出乙肝疫苗与不同动物种群的相关性。结果重组乙肝疫苗（酿酒酵母）经BALB／c鼠检测疫苗的ED50值为2．5μg／ml；经1号种群NIH鼠检测疫苗的ED。值为2．0μg／ml；经2号种群NIH鼠检测疫苗的ED50值为1．3μg/ml；经3号种群NIH鼠检测疫苗的ED50值为2．3μg/ml；经上海某公司DBA／1鼠检测疫苗的ED50值为0．8μg／ml，对乙肝疫苗的效力反应最强。根据《中国药典》2005年版三部的规定，疫苗的ED50值为≤1．5μG/ml。所以得出的结果是2号种群NIH鼠和DBA／1鼠检测疫苗是合格的。基因检测结果DBA／1为H-2^q近交系小鼠，2号种群NIH鼠含有H-2^q型基因的百分比是96％，3号种群NIH鼠含有H-2^q型基因的百分比是30％，而1号种群NIH小鼠含有H-2^q型基因百分比为56％，因此DBA／1小鼠和2号种群NIH鼠对乙肝疫苗均产生高应答效应，且远远高于免疫基因型为H-2^d的BALB／c小鼠。结论在进行乙肝疫苗效力鉴定时选择含有q型基因较多的NIH小鼠作为检测动物可以取得较好的应答效果。

Objective To test the potency of hepatitis B vaccine in China. Methods Two inbred strains（ DBA/1 and BALB/c） and two NIH closes-colonies of mice were typed in the H-2 region by microcytotoxicity method and PCR. Groups of mice of the tested strains were immunized with the same hepatitis B vaccine, the titre of anti-HBsAg antibody was analyzed by microplate, and the ED50 was then estimated by Karder method for each strain. Results Significant differences were found between potency estimates derived from assays using different strains of mice. Conclusion It is likely that the variation of immune response to hepatitis B vaccine in mice is correlative with the H-2 haplotype. In some special case, the heterozygosity in H-2 region found in NIH stock could influence the accuracy in such testing even a reference preparation of hepatitis B vaccine was used. Base on our experiment, to select an appropriate NIH stocks with the H-2^q haplotype for potency testing of hepatitis B vaccine in China.