Abstract：
Inactivated Polio Vaccines (IPV) and live Oral Polio Vaccine (OPV) were introduced in the mid-20th century, and their coordinated worldwide use led to almost complete elimination of the disease, with only one serotype of poliovirus remaining endemic in just two countries. Polio eradication will lead to discontinuation of OPV use and its replacement with IPV or other vaccines that are currently under development that will need to be tested in clinical trials. Despite decades of research, questions remain about the serological correlates of polio vaccine efficacy, specifically whether the vaccines are equally protective against immunologically different strains of the same serotype. The absence of significant morbidity does not allow use of a protection endpoint in clinical trials, so the answer could be obtained only by using surrogate markers such as immunogenicity. In this study, a panel of wild and vaccine-derived polioviruses of serotype 1 were tested in neutralization assays with sera from vaccine-immunized individuals. The results demonstrated that there was a significant difference in titers of neutralizing antibodies in human sera when measured against different strains. When measured with a homologous strain used for vaccine manufacture all subjects had detectable levels of antibodies, while neutralization tests with some heterologous strains failed to detect neutralizing antibodies in a number of subjects. Administration of a booster dose of IPV led to a significant increase in neutralizing titers against all strains. Results of the experiments using animal sera, performed to obtain more information on protectivity of neutralizing antibodies against heterologous strains, were consistent with the results obtained in the assays using human sera. These results are discussed in the context of serological biomarkers of protection against poliomyelitis, suggesting that potency of vaccines made from serologically different strains should be determined against both homologous and heterologous challenge viruses.
摘要：
脊髓灰质炎灭活疫苗（IPV）和口服脊髓灰质炎活疫苗（OPV）在20世纪中叶推出。它们在全球范围内的协调使用几乎完全消除了这种疾病，只有一种血清型的脊髓灰质炎病毒在两个国家仍然流行。根除脊髓灰质炎将导致OPV停止使用，并用目前正在开发的IPV或其他需要在临床试验中进行测试的疫苗替代。尽管经过几十年的研究,关于脊髓灰质炎疫苗效力的血清学相关性问题仍然存在，特别是疫苗是否对相同血清型的免疫不同菌株具有同等保护作用。没有显著的发病率不允许在临床试验中使用保护终点，因此，只有通过使用免疫原性等替代标记才能获得答案。在这项研究中,对一组野生和疫苗衍生的1型脊髓灰质炎病毒进行了中和试验,检测了来自疫苗免疫个体的血清.结果表明,当针对不同菌株测量时,人血清中的中和抗体的滴度存在显著差异。当用用于疫苗制造的同源菌株测量时，所有受试者的抗体水平均可检测到，而使用一些异源菌株的中和测试未能在许多受试者中检测到中和抗体。施用加强剂量的IPV导致针对所有菌株的中和滴度显著增加。使用动物血清的实验结果，进行以获得有关中和抗体对异源菌株的保护性的更多信息，与使用人血清的测定中获得的结果一致。这些结果在预防脊髓灰质炎的血清学生物标志物的背景下进行讨论，这表明，应该确定由血清学上不同的菌株制成的疫苗对同源和异源攻击病毒的效力。
