巴尔通体体外侵染巨噬细胞特性研究

Study on Characteristic of Bartonella infecting Macrophage in vitro

巴尔通体(Bartonella)是一类革兰氏阴性、营养需求苛刻的兼性胞内需氧菌,感染导致人类罹患猫抓病及杆菌样血管瘤。组织病理学研究结果发现淋巴结内存在大量巴尔通体,提示巴尔通体具有能逃避宿主先天免疫吞噬的功能。然而目前关于巴尔通体与巨噬细胞间相互作用的研究尚未深入开展。本研究利用鼠源巴尔通体(Bartonella tribocorum)体外感染J774A、RAW264.7及C57小鼠腹腔巨噬细胞,探索巴尔通体在巨噬细胞内存活特性。免疫荧光试验结果显示巨噬细胞能有效吞噬巴尔通体,细胞形态未发生显著变化。庆大霉素保护试验结果证实被吞噬的巴尔通体在不同巨噬细胞内均能增殖及存活至48h,且能在LPS诱导活化的巨噬细胞中存活。

Bartonella was fastidious gram-negative bacterium, which could cause cat scratch disease and bacillary angioma- tosis in human. Histopathology studies showed that lots of free Bartonella in infected lymph nodes, which indicated that Bar- tonella was able to escape from host innate immunity or phagocytosis. However, the interaction between Bartonella and macro- phage had not been well demonstrated. Here, intracellular survivals of Bartonella tribocorum in J774A, RAW267.4 and C57 mouse peritoneal macrophage were investigated. Gentamycin protection assay demonstrated Bartonella could replicate and sur vive in 48 hours post infection in J774A, RAW264.7 and C57 mouse peritoneal macrophages, even in LPS induced macrophages.