目的  制备重组肠道病毒71型（enterovirus A71，EV-A71）疫苗（汉逊酵母）抗原冻干参考品，用于重组EV-A71疫苗（汉逊酵母）的抗原含量测定。方法  选取检定合格的重组EV-A71疫苗（汉逊酵母）原液，加入冻干保护剂，冷冻干燥制备重组EV-A71疫苗（汉逊酵母）抗原冻干参考品，对其进行保护剂抗原含量标定，并对其进行反复冻融试验，37 ℃、2~8 ℃和-20 ℃稳定性研究。结果  制备的抗原冻干参考品鉴别试验、无菌检查结果均符合规定，水分含量为1.4%。经标定，几何均值为2 146 U/ml，几何变异系数为7.2%。10次反复冻融，抗原含量仍无明显变化；37 ℃放置3个月，抗原含量无明显变化；2~8 ℃和-20 ℃分别放置30个月，抗原含量仍较为稳定。 结论  制备了一批稳定的、均一性良好的抗原冻干参考品，可以用于重组EV-A71型疫苗（汉逊酵母）抗原含量测定。

Objective  To prepare a lyophilized reference antigen of recombinant enterovirus 71 vaccine (Hansenula) for the determination of antigen content of recombinant EV-A71 vaccine (Hansenula). Methods  Bulk of qualified recombinant EV- A71 vaccine (Hansenula) was selected as the raw material of reference, adding freeze-dried protective agent, then lyophilized to prepared freeze-dried recombinant EV-A71 (Hansenula) vaccine antigen reference, after the calibration on the antigen content, the reference was carried on the freeze-thaw test, stored at 37 ℃, 2-8 ℃ and -20 ℃ for the stability study. Results  All the quality indexes of prepared reference met the relevant requirements, and the moisture content was 1.4%. After calibration, geometry mean of reference antigen content was 2 146 U/ml and geometric variation coefficient was 7.2%.There was no significant change in antigen content after repeated freezing and thawing for 10 times. There was no significant change in antigen content for 3 months at 37 ℃.The antigen content remained stable at 2-8 ℃ and -20 ℃ for 30 months, respectively. Conclusion  A batch of stable and homogeneous reference antigens were prepared, which could be applied for the determination of antigen content in recombinant EV-A71 vaccine (Hansenula).