目的　制备A群脑膜炎球菌多糖 (PS)结合物 ,观察其免疫原性。方法　A群脑膜炎球菌多糖经溴化氰活化后共价接上己二酰肼手臂 ,在碳二亚胺催化下与精制破伤风类毒素 (TT)偶联制备结合物。单独多糖、多糖结合物和TT按相同程序免疫NIH小鼠 ,用ELISA法检测小鼠血清抗多糖抗体滴度和特异性及抗TT抗体滴度。结果　用上述实验方法制备的结合物具有多糖和蛋白质的抗原性 ,免疫小鼠可诱导高滴度的血清抗多糖IgG抗体 ,免疫 2针后高滴度抗体至少持续存在 3周。血清抗体可中和多糖。加强免疫提示有免疫记忆性。结合物还可诱导产生一定水平的TT抗体。结论A群脑膜炎球菌多糖结合到TT上可明显增强多糖在小鼠中的免疫原性 ,为制备结合疫苗并研究其对婴幼儿的免疫原性提供了实验基础 Objective To prepare Group A meningococcal polysaccharide (PS) conjugates and observe their immunogenicity. Method A Group meningococcal polysaccharide activated by cyanogen bromide is covalently linked to an adipic hydrazide arm and conjugated to purified tetanus toxoid (TT) under carbodiimide catalysis to prepare a conjugate. NIH mice were immunized with polysaccharide, polysaccharide conjugate and TT respectively. Titers and specificity of anti-polysaccharide antibody and anti-TT antibody titers were detected by ELISA. Results The conjugate prepared by the above experimental method possessed the antigenicity of polysaccharide and protein. The immunized mice could induce high titers of serum anti-polysaccharide IgG antibody, and the high titer antibody was maintained for at least 3 weeks after 2 doses of immunization. Serum antibodies neutralize polysaccharides. Strengthen immunity prompt immune memory. The conjugate can also induce the production of a certain level of TT antibody. Conclusion The binding of meningococcal serogroup A to TT can significantly enhance the immunogenicity of polysaccharide in mice, which provides the experimental basis for the preparation of conjugate vaccine and its immunogenicity to infants and young children