制备疫苗用W135/Y群脑膜炎球菌菌种的免疫原性及遗传稳定性观察

目的 为保证生产四价流脑(A、C、W135、Y群)结合疫苗质量一致性和可控性,对分离自国内的W135、Y群脑膜炎球菌CMCC(B)29037株和CMCC(B)29028株进行免疫原性及遗传稳定性观察.方法 将W135/Y群脑膜炎球菌工作种子批菌种分别连续传代至30代,并收获3、5、10、15、20、25及30代次菌液,对各代次菌进行免疫原性、抗原性、生化反应、毒性、毒力测定,并将30代次菌发酵培养后提取荚膜多糖进行质量分析.结果 CMCC(B)29037株和CMCC(B)29028株工作种子批菌种诱导小鼠产生总IgG抗体分别为1∶1114和1∶2229,杀菌抗体水平与IgG抗体间差异无统计学意义;试管凝集效价均达到1∶320,生化检定两菌株均发酵葡萄糖、麦芽糖,不发酵果糖、蔗糖、甘露醇和乳糖;两菌株的LD50均＞109,30代次内各代次菌的免疫原性、抗原性、生化反应和毒性均无差异.30代次菌液脑腔毒性测定显示均无病理改变,用第30代次菌生产的W135/Y群脑膜炎球菌荚膜多糖各项检定指标均合格.结论 分离自国内的CMCC(B)29037株和CMCC(B)29028株为脑膜炎球菌W135/Y群菌株,免疫原性、抗原性好,生化反应合格、安全性良好,连续传至30代次仍保持较好的安全性和免疫原性,30代次菌纯化的W135/Y群脑膜炎球菌荚膜多糖质量符合质控要求,可以用作四价流脑结合疫苗生产株.

Immunogenicity and hereditary stability of Neisseria meningitidis serogroup W135/Y strains used in conjugate vaccine production

Objective To evaluate the immunogenic stability and hereditary stability of Neisseria meningitides serogroup W135/Y[CMCC(B)29037/CMCC(B)29028]within all the passages,which isolated from china.Methods The toxicity of the 3rd,5th,10th,15th,20th,25th and 30th passage of the Neisseria meningitidis was assayed in mice.Serological detection and biochemical detection were measured,and immunized mice subcutaneously.The antigeeicity of each passage of Neisseria meningitides serogroup W135/Y were measured by serum bactericidal test and the indirect ELISA.With the 30 passage of Neisseria meningitides serogroup W135/Y,the effect to the encephalic tissue was measured in mice.Fermented the Neisseria meningitides serogroup W135/Y with 30 passage and purified the capsular polysaccharide,then analyzed the quality respectively.Results The LD50 of the strains CMCC(B)29037/29028 of each passage was low(LD50 ≥ 109),and all the 30logical detection and all the 30 passage of the two strains were half in the tube agglutination.Glucose and maltose fermentation test were positive.Fructose,sucrose and lactose fermentation test were negative.The GMT of immunogenicity were 1114 and 2229 respectively and all the 30 passage were more than 640 and 1040 respectively.After Immunization with individual 30 passage of the Neisseria meningitides,the titer in serum bactericidal assay(SBA)and indirect ELISA were no difference.The capsular polysaccharide purified from Neisseria meningitides serogroup W135/Y met the quality standard.Conclusion Neisseria meningitides serogroup W135/Y,CMCC(B)29037/29028,used in the manufacture of the meningococcal conjugate vaccine,are stable in the toxicity,antigenicity,immunogenicity.Serological detection and biochemical detection are qulified,and the capsular polysaccharide has met the quality standard.