Department of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK.
Clin Sci (Lond). 2010 Feb 9;118(9):547-64. doi: 10.1042/CS20090513.
The human species is the only natural host of Neisseria meningitidis, an important cause of bacterial meningitis globally, and, despite its association with devastating diseases, N. meningitidis is a commensal organism found frequently in the respiratory tract of healthy individuals. To date, antibiotic resistance is relatively uncommon in N. meningitidis isolates but, due to the rapid onset of disease in susceptible hosts, the mortality rate remains approx. 10%. Additionally, patients who survive meningococcal disease often endure numerous debilitating sequelae. N. meningitidis strains are classified primarily into serogroups based on the type of polysaccharide capsule expressed. In total, 13 serogroups have been described; however, the majority of disease is caused by strains belonging to one of only five serogroups. Although vaccines have been developed against some of these, a universal meningococcal vaccine remains a challenge due to successful immune evasion strategies of the organism, including mimicry of host structures as well as frequent antigenic variation. N. meningitidis express a range of virulence factors including capsular polysaccharide, lipopolysaccharide and a number of surface-expressed adhesive proteins. Variation of these surface structures is necessary for meningococci to evade killing by host defence mechanisms. Nonetheless, adhesion to host cells and tissues needs to be maintained to enable colonization and ensure bacterial survival in the niche. The aims of the present review are to provide a brief outline of meningococcal carriage, disease and burden to society. With this background, we discuss several bacterial strategies that may enable its survival in the human respiratory tract during colonization and in the blood during infection. We also examine several known meningococcal adhesion mechanisms and conclude with a section on the potential processes that may operate in vivo as meningococci progress from the respiratory niche through the blood to reach the central nervous system.
人类是脑膜炎奈瑟菌的唯一自然宿主，脑膜炎奈瑟菌是全球细菌性脑膜炎的重要病因，尽管它与毁灭性疾病有关，但脑膜炎奈瑟菌是一种常在健康个体呼吸道中发现的共生体。迄今为止，耐抗生素的脑膜炎奈瑟菌分离株相对较少，但由于易感染宿主的疾病迅速发作，死亡率仍约为 10%。此外，患有脑膜炎球菌病的患者通常会遭受许多衰弱的后遗症。脑膜炎奈瑟菌菌株主要根据表达的多糖荚膜类型分为血清群。总共有 13 个血清群已被描述；然而，大多数疾病是由仅属于五个血清群之一的菌株引起的。尽管已经针对其中一些开发了疫苗，但由于该生物体成功地逃避了免疫，包括模拟宿主结构以及频繁的抗原变异，因此开发通用的脑膜炎球菌疫苗仍然是一个挑战。脑膜炎奈瑟菌表达一系列毒力因子，包括荚膜多糖、脂多糖和许多表面表达的黏附蛋白。这些表面结构的变异对于脑膜炎球菌逃避宿主防御机制的杀伤是必要的。尽管如此，为了使其在定植时能够逃避宿主防御机制的杀伤，黏附于宿主细胞和组织仍需要保持。本综述的目的是简要概述脑膜炎奈瑟菌的携带、疾病和对社会的负担。在此背景下，我们讨论了几种可能使其在定植时在人类呼吸道中以及在感染时在血液中存活的细菌策略。我们还检查了几种已知的脑膜炎球菌黏附机制，并在结论部分讨论了脑膜炎球菌从呼吸道定植部位通过血液到达中枢神经系统过程中可能在体内发挥作用的潜在过程。
