金黄色葡萄球菌乳腺炎是影响畜牧业发展的主要疾病之一，深入研究其发病的免疫学机制已迫在眉睫。近年来研究表明，Th17细胞亚群及其分泌的主要细胞因子IL-17在胞外细菌感染和介导慢性炎症中发挥重要作用。尤其是最新研究发现，IL-17在防御皮肤金黄色葡萄球菌感染中发挥了重要的免疫保护作用，为预防和治疗金黄色葡萄球菌皮肤感染提供了新的靶点。乳腺作为机体特殊的组织器官，在金黄色葡萄球菌感染后，Th17细胞/IL-17的动态变化规律如何？发挥何种功能？尚无研究报道。因此，本项目在建立金黄色葡萄球菌感染小鼠乳腺炎模型的基础上，以Th17细胞及其主要效应因子IL-17作为研究对象，对Th17细胞及IL-17在金黄色葡萄球菌感染乳腺炎症中的应答规律和功能效应进行研究，为明确金黄色葡萄球菌乳腺炎的发病机制提供新的实验资料。

Staphylococcus aureus mastitis is the most common and costly livestock diseases.The mechanism of persistent infection of mammary gland by Staphylococcus aureus was complex and need to be understood Urgently.Several Literature indicated that Th17 cells /IL-17 are responsible for both protection and chronic status of certain infections,and recent findings highlight an important role for IL-17 in clearance of S. aureus in mouse skin providing a new target for the prevention and treatment of Staphylococcus aureus skin infections. However,the role of Th17 cells /IL-17 during mammary gland Staphylococcus aureus infection is unknown. In this study, we will investigate the role of Th17 cells /IL-17 in an mammary gland Staphylococcus aureus infection in a mouse model. This study will lay the basis to understand the role of IL-17 in the pathogenesis of Staphylococcus aureus mastitis.