Carmenate Tania, Canaán Leonardo, Alvarez Anabel, Delgado Maité, González Sonia, Menéndez Tamara, Rodés Lorenzo, Guillén Gerardo
Centre for Genetic Engineering and Biotechnology, Division of Vaccines, PO Box 6162, Havana 6, Cuba.
FEMS Immunol Med Microbiol. 2004 Apr 9;40(3):193-9. doi: 10.1016/S0928-8244(03)00346-8.
Neisseria meningitidis serogroup C polysaccharide (CCPS) was conjugated to the carrier protein P64k using two different conjugation procedures, condensation mediated by carbodiimide with adipic acid dihydrazide as spacer and the reductive amination method. BALB/c mice were immunized with the resultant polysaccharide-protein conjugates and the immune response was evaluated. All conjugates assayed generated at least 10-fold higher antibody titers than the free polysaccharide. The reductive amination method rendered the best conjugate (CCPS-P64kR) that was able to elicit antibody titers statistically higher than the titer elicited by the plain CCPS (P<0.001). The sera of the group immunized with CCPS-P64kR showed a three-fold higher bactericidal response than the sera of the group immunized with the plain CCPS and they were able to protect against challenge with meningococci in the infant rat protection model. In addition, three different conjugates were obtained from polysaccharides with molecular relative sizes of 2000-4000 Da, 4000-10,000 Da or 10,000-50,000 Da, but no differences were detected in the immune response obtained against the three conjugates. Our experiments demonstrate that it is possible to generate a protective, T-cell-dependent response against CCPS using the P64k protein as carrier.
使用两种不同的偶联方法，即碳二亚胺介导的缩合反应（以己二酸二酰肼为间隔臂）和还原胺化法，将脑膜炎奈瑟菌C群多糖（CCPS）与载体蛋白P64k偶联。用所得的多糖-蛋白偶联物免疫BALB/c小鼠，并评估免疫反应。所有检测的偶联物产生的抗体滴度比游离多糖至少高10倍。还原胺化法得到的最佳偶联物（CCPS-P64kR）能够引发统计学上高于纯CCPS引发滴度的抗体滴度（P<0.001）。用CCPS-P64kR免疫的组的血清杀菌反应比用纯CCPS免疫的组的血清高3倍，并且它们能够在幼鼠保护模型中抵御脑膜炎球菌的攻击。此外，从分子量相对大小为2000-4000 Da、4000-10,000 Da或10,000-50,000 Da的多糖中获得了三种不同的偶联物，但针对这三种偶联物获得的免疫反应未检测到差异。我们的实验表明，使用P64k蛋白作为载体有可能产生针对CCPS的保护性、T细胞依赖性反应。
