单克隆抗体在肺炎球菌多糖疫苗多糖含量检测中的应用

 目的  考察能否用单克隆抗体（单抗）替代多克隆抗体（多抗）血清检测23价肺炎球菌多糖疫苗中各型多糖的含量。方法   使用8个血清型（2、3、4、6B、9N、17F、18C、23F）的小鼠抗肺炎球菌荚膜多糖单抗和丹麦国家血清研究所（Statens Serum Institut, SSI）的兔血清多抗，以速率散射免疫浊度法测定23价肺炎球菌多糖疫苗中相应血清型的多糖含量。通过重复性和专属性试验确定单抗的可用性。采用t 检验对单抗和多抗测定结果进行比较。结果   各型单抗与多糖标准品反应标准曲线的相关系数均>0.985 0。用单抗重复检测疫苗多糖3次，质量浓度为40.8～62.1 μg/ml，3次检测结果变异系数均<8.00%。各型多糖回收率为81.6%～124.2%。分别用8个血清型单抗检测其余各型多糖含量，结果均低于或接近于检测下限。单抗与SSI多抗血清的检测结果差异均无统计学意义，t 值为0.210 3～1.926 0，P 值均>0.05。结论   单抗检测重复性好、特异性高，与多抗血清检测结果相仿，因此，单抗可以替代SSI多抗血清用于测定23价肺炎球菌多糖疫苗中的多糖含量。

Application of monoclonal antibodies in determination of polysaccharides in a pneumococcal polysaccharide vaccine

 Objective   To investigate whether polyclonal antibody sera could be replaced  moneclonal antibodies(Mabs) to determine contents of pneumococcal polysaccharides in a 23-valent pneumococcal polysaccharide vaccine (PPV23). Methods   Mouse Mabs against polysaccharides of types 2, 3, 4, 6B, 9N, 17F, 18C and 23F, and rabbit sera from Statens Serum Institut (SSI)were used. The pneumococcal polysaccharides in PPV23 were determined by rate Nephelometry. Repeatability and specificity were analyzed to evaluate the usability of Mabs. The results with two kinds of antibodies were compared by t  test. Results   When Mabs to different serotypes reacted with standard polysaccharides, all correlation coefficients of standard curves were >0.985 0. The polysaccharides in PPV23 ranged from 40.8 to 62.1 μg/ml when determined 3 times by Mabs, and the coefficients of variability were <8.00%. The recovery rates of different serotypes of polysaccharides ranged from 81.6% to 124.2%. Each Mab was used to test the other 22 serotypes of polysaccharides, the content levels were lower than or close to the lower limit of detection. No statistical difference was found between the results of Mabs and SSI sera, t values ranged from 0.210 3 to 1.926 0, and all P values were >0.05. Conclusion   The determination results of polysaccharides with Mabs are good in repeatability and specificity, and are comparable to that of sera, therefore, the Mabs could replace SSI rabbit sera for determination of polysaccharides in PPV23.