PROTECTION TEST FOR POTENCY OF POLIOVIRUS VACCINE

世界卫生组织最近未能接受IPV效力的国际标准测试。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，恒河猴的免疫原性测试需要一个敏感的物种，而且价格昂贵。1997年度，单价IPV免疫的TgPVR21小鼠对野生型3型脊髓灰质炎病毒致命攻击的保护效力试验成功推广到其他两种类型的IPV。证实了三种类型之间的抗原干扰，并且对由OPV疫苗株制备的IPV的免疫应答比从野生型病毒制备的IPV差，并发表了结果。98财年的进展受到阻碍，因为所有可用的TgPVR21小鼠都用于世卫组织TgPVR小鼠合作研究，用于检测口服脊髓灰质炎病毒。生产研究所已要求世卫组织和其他来源提供额外支持；如果有小鼠可用，它们将被用来完成这项研究，比较标准d抗原ELISA试验和大鼠免疫原性试验与tg小鼠攻击保护试验，以估计IPV制剂的效力。由于无法获得PVR Tg21小鼠进行进一步研究，该项目在1999财年处于非活动状态。但是，保留了项目编号和文件，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。2005年，在DMA/OTRR的工作人员中开始了对联合疫苗中IPV效力的小鼠试验进行验证的研究。在TgPVR小鼠中验证并与疾病保护相关的中和抗体试验目前正在常规近交系小鼠中开发，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.