PROTECTION TEST FOR POTENCY OF POLIOVIRUS VACCINE

世界卫生组织最近未能接受国际标准的IPV效力测试。目前在美国使用的测试并不理想：D抗原的ELISA测试并不总是准确地预测中和抗体反应，而且恒河猴的免疫原性测试需要敏感的物种，而且价格昂贵。在97财年，一项保护单价IPV免疫的TgPVR21小鼠免受野生型3型脊髓灰质炎病毒致死攻击的效力试验被成功地推广到其他两种类型的IPV。这三种病毒之间存在抗原干扰，OPV疫苗株对IPV的免疫应答弱于野生型IPV，并发表了研究结果。所有可用的TgPVR21小鼠都被用于世卫组织TgPVR小鼠检测OPV的合作研究，这阻碍了98财年的进展。生产研究所已经要求世界卫生组织和其他来源提供额外的支持；如果有小鼠可用，将使用它们来完成这项研究，将标准D抗原ELISA测试和老鼠免疫原性测试与TG小鼠挑战保护测试进行比较，以评估IPV制剂的效力。由于PVR Tg21小鼠无法使用，该项目在1999财年处于停滞状态，需要进行进一步的研究。然而，保留了项目编号和档案，以便进一步开发测试方法，并将其应用于DVP和其他地方关于IPV的其他项目。在2000财年，与DMA/OTRR的人员一起启动了对组合疫苗中IPV效力的小鼠测试有效性的研究。在TgPVR小鼠中验证的中和抗体检测与疾病保护相关，目前正在传统近交系小鼠中开发，以评估联合疫苗的免疫干扰。迄今为止的研究表明，对1型脊髓灰质炎病毒的反应有显著干扰。

The WHO recently failed to accept an international standard test for the potency of IPV. The tests currently used in the USA are not ideal: ELISA tests of D Antigen do not always accurately predict neutralizing antibody responses, and tests of immunogenicity for rhesus monkeys require a sensitive species and are expensive. In FY 97, a potency test for protection of monovalent-IPV-immunized TgPVR21 mice against lethal challenge with wild-type type-3 poliovirus by was successfully extended to IPV of the other two types. Antigenic interference among the three types and a poorer immune response to IPV prepared from OPV vaccine strains than to IPV prepared from wild-type virus was demonstrated and results were published. Progress in FY 98 was impeded by the fact that all available TgPVR21 mice were used for the WHO Collaborative Study of TgPVR mice for testing OPV. The producing institute has requested additional support from the WHO and other sources; if mice become available, they will be used to complete this study, comparing a standard D-antigen ELISA test and a rat-immunogenicity test with the Tg-mouse challenge-protection test for estimating potency of IPV preparations. This project was inactive in FY 99 due to unavailability of PVR Tg21 mice needed to conduct further studies. However, the project number and file were retained to allow further development of the test and application of the methods to other projects on IPV in DVP and elsewhere. In FY00, studies on validation of a mouse test for IPV potency in combination vaccines was initiated with personnel in DMA/OTRR. The neutralizing antibody assay validated in TgPVR mice and correlated with protection against disease is now being developed in conventional inbred mice to evaluate immunological interference in combination vaccines. Studies to date show significant interference to the type 1 polivirus response.