Oxford Vaccine Group, Department of Paediatrics, University of Oxford, UK.
Expert Rev Vaccines. 2011 May;10(5):673-84. doi: 10.1586/erv.11.14.
The polysaccharide-encapsulated bacteria, Haemophilus influenzae type b, Neisseria meningitidis and Streptococcus pneumoniae are important causes of invasive bacterial infection in childhood, accounting for most of the cases of bacterial pneumonia and meningitis worldwide. Protein-polysaccharide conjugate vaccines have been developed over the last 20 years and have proven very effective in controlling these infections. Although studies have consistently shown that herd immunity is critical for population protection, long-term individual protection against polysaccharide-encapsulated bacteria appears to depend on persisting antibody and, perhaps to a lesser extent, immunological memory. However, some studies have reported that the concentration of serum antibody and vaccine effectiveness are not sustained after infant immunization, despite persistence of immunological memory. In this article, we detail the mechanisms of protection against invasion by encapsulated bacteria, describe the age-dependent B-cell and antibody responses to protein-polysaccharide conjugate vaccines and propose strategies to guarantee protection during periods of increased disease burden.
荚膜多糖包被菌，如流感嗜血杆菌 b 型、脑膜炎奈瑟菌和肺炎链球菌，是儿童侵袭性细菌感染的重要病因，占全世界细菌性肺炎和脑膜炎的大多数病例。过去 20 年来，已经开发出了蛋白多糖结合疫苗，并且在控制这些感染方面已被证明非常有效。尽管研究一直表明群体免疫对于人群保护至关重要，但针对荚膜多糖包被菌的长期个体保护似乎取决于持续存在的抗体，或许在较小程度上还取决于免疫记忆。然而，一些研究报告指出，尽管存在免疫记忆，但在婴儿免疫接种后，血清抗体浓度和疫苗有效性无法持续。在本文中，我们详细描述了针对荚膜细菌侵袭的保护机制，描述了针对蛋白多糖结合疫苗的年龄依赖性 B 细胞和抗体反应，并提出了在疾病负担增加期间保证保护的策略。
