弓形虫钙依赖蛋白激酶对天然免疫应答调控机制的研究

弓形虫病是一种重要的人兽共患病，不仅严重威胁人类健康，而且是食品安全与畜牧业发展的重要隐患。制约有效防控弓形虫病的主要原因是欠缺对该病的基础研究，尤其是对弓形虫入侵宿主引起的机体天然免疫应答的调节机制尚需进一步研究。钙依赖蛋白激酶(CDPK)在弓形虫中有12个成员，参与调节弓形虫的滑动、入侵、增殖及释放等重要生命过程，但是CDPK对宿主的免疫调节机制尚不明确。我们通过敲除弓形虫TgCDPK5，发现其与虫体生长发育密切相关，但具体机制尚不明确。本项目拟在前期研究基础上，构建与入侵相关的TgCDPK5缺失株、TgCDPKx 缺失株以及TgCDPK5/x 双基因缺失株，鉴定其生物学特性；通过蛋白或缺失株分别刺激DC细胞、巨噬细胞、小鼠脾细胞以及小鼠，分析天然免疫通路中相关因子的表达变化情况，解析弓形虫CDPK对天然免疫应答的调控机制，为阐明弓形虫入侵及感染的致病机制奠定基础。

Toxoplasmosis is an important zoonotic disease，it is not only a serious hazard to human health, but also detrimental to food safety and the animal husbandry production. The main reason that toxoplasmosis has not been controlled well is due to the insufficiency in its basic research, particularly it is yet to understand the mechanism of the innate immune of its hosts during the infection.There are 12 members in calcium-dependent protein kinases（CDPK）family in Toxoplasma gondii, which regulate diverse important processes including gliding, invasion, proliferation and egress. However, the mechanism of immune regulation is still unknown. We found that TgCDPK5 is a stress response protein associated with T. gondii growth and development. However, the mechanism of action is still unclear. In the present study, we will construct TgCDPK5-deficient strain, TgCDPKx-deficient strain, and TgCDPK5/x double genes-deficient strain, whose biological characteristics will be further determined. The protein or the deficient stains will be used to stimulate DCs, macrophage, spleen cells of mouse, and mice, respectively, and the cytokines in innate immune pathway will be analyzed to study the mechanism of innate immune regulated by CDPKs.The expected results would contribute to better understand the relationship relating to invasion and pathogenesis.