非疫苗血清型肺炎链球菌发生机制及疫苗新策略

肺炎链球菌(Streptococcus pneumoniae,Sp)是社区获得性肺炎以及侵袭性疾病如脑膜炎和败血症的主要致病菌之一,到目前为止,关于肺炎链球菌感染性疾病的预防仍以肺炎链球菌多糖疫苗(pneumococcal polysaccharide vaccine,PPV)和肺炎链球菌多糖蛋白结合疫苗(pneumococcal conjugate vaccine,PCV)为主。然而靶向特定荚膜多糖的肺炎链球菌疫苗的选择性压力在一定程度上诱导了肺炎链球菌荚膜转换,导致了不同荚膜抗原突变体的产生,进而造成非疫苗血清型(non-vaccine type,NVT)及无荚膜肺炎链球菌(nonencapsulated streptococcus pneumoniae,NESp)的增加,使现有的疫苗不能有效预防肺炎链球菌的感染。本文重点介绍了肺炎链球菌非疫苗血清型的发生机制,为制备新型肺炎链球菌疫苗提供思路与策略。

Mechanisms and new vaccine strategies for Streptococcus pneumoniae non-vaccine serotypes

Streptococcus pneumoniae is one of the main pathogens causing community-acquired pneumonia and invasive diseases such as meningitis and septicemia. To date, pneumococcal polysaccharide vaccines and pneumococcal conjugate vaccines remain the main methods to prevent Streptococcus pneumoniae infection. However, selective pressure on Streptococcus pneumoniae vaccines targeting specific capsular polysaccharide induces capsule switching to some extent, thus resulting in the production of mutants expressing different capsular antigens, and leading to an increase in non-vaccine types and nonencapsulated Streptococcus pneumoniae. Consequently, the existing vaccines cannot effectively prevent Streptococcus pneumoniae infection. This article focuses on the mechanisms of non-vaccine serotypes of Streptococcus pneumoniae, to provide ideas and strategies for the preparation of new vaccines for Streptococcus pneumoniae.