Saito Y, Fujii R, Nakagawa K-I, Kuramitsu H K, Okuda K, Ishihara K
Department of Endodontics, Pulp and Periapical Biology, Tokyo Dental College, Chiba, Japan.
Oral Microbiol Immunol. 2008 Feb;23(1):1-6. doi: 10.1111/j.1399-302X.2007.00380.x.
BACKGROUND/AIMS: Bacterial infection is a major cause of periapical periodontitis. Eradication of these microorganisms from apical lesions is essential to the success of endodontic treatment. The aim of this study was to clarify the molecular interaction between Fusobacterium nucleatum, Porphyromonas gingivalis and other microorganisms associated with periapical periodontitis.
Microorganisms isolated from periapical lesions were inoculated into type-I collagen-coated polystyrene microtiter plates and maintained at 37 degrees C under anaerobic conditions for 2 days, after which, the quantity of organized biofilm on the plates was evaluated by crystal violet staining. Growth enhancement via soluble factor was evaluated by separated coculture using a 0.4-mum membrane filter.
F. nucleatum exhibited strong adherence to type-I collagen-coated polystyrene microplates. Biofilm formation by F. nucleatum was significantly enhanced by P. gingivalis. It was complemented by compartmentalized coculture with P. gingivalis. Enhancement of biofilm formation by P. gingivalis was only slightly reduced by inactivation of its autoinducer-2-producing gene luxS.
The results suggest that P. gingivalis enhances biofilm formation by F. nucleatum by releasing diffusible signaling molecules other than autoinducer-2.
背景/目的：细菌感染是根尖周炎的主要病因。从根尖病变中根除这些微生物对于牙髓治疗的成功至关重要。本研究的目的是阐明具核梭杆菌、牙龈卟啉单胞菌与其他与根尖周炎相关微生物之间的分子相互作用。
将从根尖病变中分离出的微生物接种到I型胶原包被的聚苯乙烯微量滴定板中，在37℃厌氧条件下培养2天，之后，通过结晶紫染色评估板上形成的生物膜数量。通过使用0.4μm膜过滤器进行分离共培养来评估可溶性因子对生长的促进作用。
具核梭杆菌对I型胶原包被的聚苯乙烯微孔板表现出强烈的粘附。牙龈卟啉单胞菌显著增强了具核梭杆菌的生物膜形成。与牙龈卟啉单胞菌进行分隔共培养可起到补充作用。牙龈卟啉单胞菌生物膜形成的增强仅因其自诱导物-2产生基因luxS的失活而略有降低。
结果表明，牙龈卟啉单胞菌通过释放除自诱导物-2之外的可扩散信号分子来增强具核梭杆菌的生物膜形成。
