细菌蛋白的免疫学特性及其作为多糖蛋白结合疫苗载体的可行性

Immunological properties of bacterial protein and its feasibility as a polysaccharide-protein conjugate vaccine carrier

多糖蛋白结合疫苗(polysaccharide-protein conjugate vaccine)是将病原菌的荚膜多糖与载体蛋白通过共价结合的方式制备而成的疫苗。在上市的多糖蛋白结合疫苗中,载体蛋白(carrier protein)预先接种或共同接种时可能介导免疫干扰,降低结合物中多糖的免疫应答,影响疫苗接种效果。另外,多糖作为疫苗抗原有血清型别的限制,疫苗中所含的血清型别无法保护所有型别的细菌感染。因此,考虑将细菌自身具有保护性的抗原蛋白作为载体蛋白,其中,肺炎链球菌溶血素蛋白、金黄色葡萄球菌蛋白、B群链球菌菌毛蛋白和沙门菌表面蛋白都是目前经过实验室证实的具有免疫原性的载体蛋白。现对这些细菌蛋白的免疫学特性及其作为多糖蛋白结合疫苗载体的可行性作一概述。

The polysaccharide-protein conjugate vaccine is prepared by binding the capsular polysaccharide of pathogenic bacteria with the carrier proteins covalently. The marketed polysaccharide-protein conjugate vaccine may lead to immune interference that reduces the immune response to polysaccharides of conjugate vaccines due to prior or common vaccination of carrier protein. In addition, as vaccine antigen, polysaccharides are limited by serotypes and cannot protect against bacterial infections of all serotypes. Therefore, protective protein antigens of bacteria are considered as carrier proteins. Among which, Streptococcus pneumoniae hemolysin proteins, Staphylococcus aureus autoproteins, group B Streptococcus pili proteins and Salmonella surface proteins are currently confirmed as carrier proteins with immunogenicity. In this review, the immunological properties of those bacterial proteins and their feasibility as conjugate vaccine carriers are summarized.