The Spr1875 protein confers resistance to the microglia-mediated killing of Streptococcus pneumoniae

作者：Peppoloni Samuele^*; Colombari Bruna; Beninati Concetta; Felici Franco; Teti Giuseppe; Speziale Pietro; Ricci Susanna; Ardizzoni Andrea; Manca Lidia; Blasi Elisabetta

来源：Microbial Pathogenesis, 2013, 59-60: 42-47.

DOI：10.1016/j.micpath.2013.04.002

• Streptococcus pneumoniae
• Protein antigen
• Microglia
• Phagocytosis
• Intracellular survival
• Killing

By screening a whole-genome lambda-display library of Streptococcus pneumoniae, we have previously identified a novel surface protein, named Spr1875, that exhibited immunogenic properties and was closely related to pneumococcal virulence. In the present study, we investigated the role of the Spr1875 antigen in the interaction of S. pneumoniae with microglia, the resident brain macrophages. By using an in vitro infection model, the BV2 microglial cell line was challenged with the S. pneumoniae strain DP1004 and its isogenic spr1875-deleted mutant (Delta spr1875). Both strains were phagocytosed by microglia efficiently and to a similar extent; however, the DP1004 strain was more resistant than the Delta spr1875 mutant to the intracellular killing, as assessed by antibiotic protection and phagosome maturation assays. Moreover, significant differences between the two strains were also observed in terms of susceptibility to microglia-mediated killing. Taken together, these results indicate that S. pneumoniae-microglial cell interplay is influenced by the presence of Spr1875, suggesting that this protein may play a role in the pathogenesis of pneumococcal meningitis.

• 出版日期2013-7