前期研究表明，肺炎链球菌减毒活疫苗SPY1在预防肺炎链球菌感染中有一定的潜力。我们在研究其介导的Th17免疫应答的机制中，发现SPY1能够有效刺激树突状细胞表达各种细胞因子，其中IL-27表达明显上调。文献报道，IL-27作为一种多效性细胞因子在疫苗抗感染中发挥重要作用。但其在疫苗SPY1介导的免疫保护中的作用及机制尚不清楚。本研究拟通过基因缺陷小鼠模型、体外细胞模型以及小鼠免疫、肺炎链球菌定植和侵袭感染模型，采用荧光定量PCR、流式细胞术、ELISA等检测技术研究IL-27在SPY1引起的免疫保护中的作用及具体机制。本研究可为该疫苗进一步研发提供理论依据，也可为肺炎链球菌疫苗乃至其它细菌的疫苗或佐剂的设计和研发提供新思路。

Previous study shown that Streptococcus pneumoniae SPY1 has potenial to be a candidate live attenuated vaccine protect against Streptococcus pneumoniae. In our later mechanisms study of SPY1 induced Th17 immune response, found that DC could be effect activated by SPY1, and several cytokines expression increased, such as TNF-α, IL-6, IL-12, IL-1βand IL-27. It is reported that IL-27, as a multi-effect cytokine, play a provital role in vaccines induced protection against infection. However, it is still unclear the effect and mechanism of IL-27 in vaccine SPY1 induced protection against Streptococcus pneumoniae. In this study the effects and mechanisms of IL-27 in SPY1 induced protection will be systematically explored from several aspects including gene knockout mice mode, cell mode, mice immunization, colonization and invasion of Streptococcus pneumoniae will be established,and techniques such as real-time PCR, ELISA and flow cytometry will be used. This research will not only provide theoretical basis and experimental basis for further development of this candidate vaccine but also afford some novel ideas for exploring the immune protection mechanisms of other kinds of Streptococcus pneumoniae vaccines as well as adjuvant and vaccines of other bacteria strains.