A群C群脑膜炎球菌结合疫苗的制备

目的制备A群C群脑膜炎球菌结合疫苗,并对其进行生化检测及免疫原性和抗原性分析。方法经溴化氰(CNBr)分别活化的A群、C群脑膜炎球菌荚膜多糖,在己二酰肼(ADH)的连接作用和碳二亚胺(EDAC)的偶联作用下,与破伤风类毒素(Tetanic toxoid,TT)形成结合物。以不同剂量的GAMP-TT和GCMP-TT的混合物免疫小鼠,检测小鼠血清中GAMP、GCMP和TT的抗体滴度,评价其免疫效果。根据剂量试验结果,制备A群C群脑膜炎球菌结合疫苗并进行抗原性检测,并与市售同类产品进行对比试验。结果制备的3批GAMP-AH和3批GCMP-AH的批间差异较小,GAMP-AH和GCMP-AH的衍生率相差较大,由GCMP-AH制备的GCMP-TT的结合率明显高于GAMP-TT(P<0.01),结合物含量差异无统计学意义(P>0.05)。GAMP-TT和GCMP-TT具有良好的免疫原性和抗原性,多糖蛋白结合物组较多糖组可诱导产生更高水平的GAMP和GCMP抗体,且具有免疫记忆。由以上两者制备的A群C群脑膜炎球菌结合疫苗生化指标、血清抗体效价与市售的同类产品差异无统计学意义(P>0.05)。结论成功研制了具有良好免疫原性和抗原性的A群C群脑膜炎球菌结合疫苗,为其产业化奠定了基础。

Preparation of groups A and C meningococcal conjugate vaccine

Objective To prepare group A and group C meningococcal conjugate vaccine,determine its biochemical characteristics and analyze its immunogenicity and antigencity.Methods Meningococcal capsular polysaccharide groups A and C were activated with cyanogen bromide(CNBr) respectively and conjugated to tetanus toxoid(TT) using adipic acid dihydrazide(ADH) as a linker and 1-ethyl-3-(3-dimethylam ino-propyl) carbodiimide(EDAC) as a coupling reagent.Mice were immunized s.c.with the mixture of GAMP-TT and GCMP-TT at various dosages,and determined for antibody titers against GAMP,GCMP and TT in sera,based on which the immune effect was evaluated.According to the results of three dosage trials,groups A and C meningococcal conjugate vaccine was prepared and determined for antigenicity,and the result was compared with that of commercial product of the same kind.Results The ADH contents in various batches of GAMP-AH and GCMP-AH showed no significant difference.However,the derivation rates of GAMP-AH and GCMP-AH showed significant difference.The yield of GCMP-TT was significantly higher than that of GAMP-TT(P < 0.01),while the polysaccharide content showed no significant difference(P > 0.05).Both GAMP-TT and GCMP-TT showed high immunogenicity and antigenicity,by which the antibody levels induced were significantly higher than those by polysaccharide alone,and an immunological memory was induced as well.The biochemical indexes and serum antibody titers of prepared groups A and C meningococcal conjugate vaccine showed no significant difference with those of commercial products of the same kind(P > 0.05).Conclusion Groups A and C meningococcal conjugate vaccine with high immunogenicity and antigenicity was successfully prepared,which laid a foundation of industrialization of the vaccine.