The Preliminary Stydy On Effect Of Adjuvant Adding In Sabin Strain Inactivated Polioviurs Vaccine(Sabin IPV) In Rats

As approaching of the aim of eradicating poliomyelitis all around the world, the circulating of vaccine-derived poliovirus(VDPV) and the occuring of vaccine-associated paralytic poliomyelitis(VAPP) became a big threaten to consolidate the goal of polio-free state. At the end of global polio eradication campaign, We should eradicate the wild-type polioviru as quickly as possile and using inactivated polio vaccine(IPV) to replase oral polio vaccine(OPV) to maintain the state of polio-free. WHO encouraged vaccine manufactures to develop IPV prepared with attenuated virus, Sabin strain, in consideration of biological safe factors durning vaccine producing.For the reason that there is no Sabin IPV product has been approved to appear on the market, there has no uniformed determining methods nor authortied quality control standard for Sabin IPV. As long as former research showed that Sabin IPV was different frome wild type IPV (WT IPV) in many aspects, so we need to establish new methods to determine the content of D antigen and content of protein which adapted to Sabin IPV. Further more, we research on the effect of adjuvant on Sabin IPV, to discuss the potential to use adjuvant for improving immunogenicity of Sabin IPV and the appropriate dose of the adjuvant.In Part 1 of the study, we found out suitable concentrations of reactors, then optimized recation conditions(including tempreture and time, ect), to build a stable, accurate ELISA system for determining the content of D antigen in the vaccine. And we also changing different conditoions to optimize the experiment to establish an improved lowry method to determine the content of protein in Sabin IPV. The method can exclude the interference of free aminoacid, phenols and some other additives. The calibration curve was in good linearity of Protein wihtin the range of 2.5μg / ml-40μg / ml, r=0.9998. Under the best conditons, the mean recovery was 95.32%, the CV in a batch and between batchs were both <10%.In Part 2 of the study, trivalence Sabin IPV(each dose containing type I 15DU, type II 16DU and type III 22.5DU) were preparde by adding of adjuvanticity of Al(OH)₃, DC-Chol and Al(OH)₃+DC-Chol, then compared effects on both humoral immunity and cellular immunity in Wistar rats. Results of serum neutralization test showed that the position rates of type I,II and III neutralizing antibody were generally increasing by adding adjuvants after the 1^st dose. And the 3 kinds of adjuvant can all increase type II neutralizing antibody after the 2^nd dose. The potency of neutralizing antibody varied form group to group. Generally speaking, adding adjuvant could enhance the potency. Al(OH)₃ or/and DC-Chol could stimulate high potency of type I and type IIIneutralizing antibody, which means these adjuvants could enhance type I and type IIIneutralizing antibody level in earlier period. And the ELISPOT results indicated that Al(OH)₃ or DC-Choi could slightly improve poliovirus-specific cellular immunity function. Furthermore, the results of FCM displayed that Al(OH)₃ orDC-Choi could increase the value of CD3⁺CD4⁺/CD3⁺CD8⁺, which implied these two adjuvants has immune-enhancing ability.