University of Guelph, Guelph, ON, N1G 2W1, Canada.
Expert Rev Vaccines. 2013 Apr;12(4):421-31. doi: 10.1586/erv.13.9.
Clostridium difficile is responsible for thousands of deaths each year and a vaccine would be welcomed, especially one that would disrupt bacterial maintenance, colonization and persistence in carriers and convalescent patients. Structural explorations at the University of Guelph (ON, Canada) discovered that C. difficile may express three phosphorylated polysaccharides, named PSI, PSII and PSIII; this review captures our recent efforts to create vaccines based on these glycans, especially PSII, the common antigen that has precipitated immediate attention. The authors describe the design and immunogenicity of vaccines composed of raw polysaccharides and conjugates thereof. So far, it has been observed that anti-PSII antibodies can be raised in farm animals, mice and hamster models; humans and horses carry anti-PSII IgA and IgG antibodies from natural exposure to C. difficile, respectively; phosphate is an indispensable immunogenic epitope and vaccine-induced PSII antibodies recognize PSII on C. difficile outer surface.
艰难梭菌每年导致数千人死亡，人们迫切需要开发一种疫苗，尤其是能够破坏细菌在携带者和恢复期患者体内维持、定植和持续存在的疫苗。安大略省圭尔夫大学的结构探索发现，艰难梭菌可能表达三种磷酸化多糖，分别命名为 PSI、PSII 和 PSIII；本综述介绍了我们最近基于这些糖开发疫苗的努力，特别是 PSII，这是一种常见抗原，引起了人们的立即关注。作者描述了由原始多糖及其缀合物组成的疫苗的设计和免疫原性。到目前为止，已经观察到抗 PSII 抗体可以在农场动物、小鼠和仓鼠模型中产生；人类和马分别从接触艰难梭菌中携带抗 PSII IgA 和 IgG 抗体；磷酸是不可或缺的免疫原表位，疫苗诱导的 PSII 抗体识别艰难梭菌外表面的 PSII。
