奶牛乳腺炎无乳链球菌毒力相关因子

Advances on Virulence Factors of Streptococcus agalactiae of Dairy Cows Mastitis

链球菌、金黄色葡萄球菌和大肠杆菌是引起奶牛乳腺炎的3大病原菌,在链球菌属中无乳链球菌是引起奶牛乳腺炎的重要病原菌之一,由无乳链球菌导致的乳腺炎约占隐性乳腺炎发病率的56.25%。无乳链球菌入侵奶牛乳腺的过程主要包括感染、黏附上皮细胞、侵入上皮细胞、损伤机体和免疫逃避等过程。无乳链球菌的毒力因子具有附着和侵袭机体细胞的作用,使菌体在奶牛乳腺表面形成生物被膜,进而干扰机体的正常免疫功能并引起疾病。本文主要阐述了无乳链球菌在入侵乳腺组织过程中发挥主要作用的毒力因子的种类、作用机制以及调控过程,旨在通过抑制其相关毒力因子的活性,从而阻断无乳链球菌在乳腺中感染和传播,进而为预防和治疗链球菌型乳腺炎提供新的思路。

Streptococcus,Staphylococcus aureus,and Escherichia coli are the three major pathogens causing mastitis in dairy cows,and Streptococcus agalactiae(S.agalactiae)in Streptoco-ccus is one of the important pathogens causing mastitis in dairy cows,which accounts for around 56.25%of the incidence of sub-clinic mastitis.The process of S.agalactiae invasion mammary glands of dairy cows mainly includes:infection,adhesion,invasion,and then damage the mammary tissue and entail the inflammation.The virulence factor of S.agalactiae has the function of attaching and invading the mammary gland epithelial cells so that the bacteria could form the biofilm on the surface.After infection,the irritation of the mammary tissues by infectious processes serves to the immune response.In this paper,we summarized the types,mechanism,and regulation process of S.agalactiae virulence factors which plays a major role in the invasion of mastitis,aimed to show the activity of S.agalactiae by inhibiting the activity of its related virulence factors in preventing dairy cow mastitis and provide new ideas for the treatment.