Th2极化对牙周炎保护作用的实验研究

目的:探讨稳定机体免疫反应对牙周组织病变的免疫调节作用,为牙周炎的免疫防治提供实验依据.方法:选用36 只SPF级12周龄雄性KM小鼠,随机分成3 组:正常对照组;牙周炎组,采用丝线结扎牙颈部并接种牙周炎患者病变区域龈缘下细菌诱导实验性牙周炎模型;Th2极化组,同上法复制实验性牙周炎模型,于术后第0 d感染低剂量旋毛虫.正常对照组及各实验组分别于术后第1、4、8、12 周分批处死动物,进行组织学观察和血清细胞因子IFN-γ、IL-4检测.结果:牙周炎组的牙周组织表现为中等程度的炎症破坏,而Th2极化组的牙周破坏程度较牙周炎组轻.牙周炎组血清IFN-γ含量较Th2极化组明显升高(P<0.01); Th2极化组IL-4含量较牙周炎组明显升高(P<0.01).结论:牙周炎的发病过程与Th1/Th2免疫应答平衡的失调有密切关系,表现为Th1细胞功能相对亢进,Th2细胞功能不足;Th2型细胞因子可有效减轻病变程度,对牙周组织具有保护作用.

The effects of intestinal nematode infection on experimental periodontitis in mice

Objective: To investigate the effect of polarizing the immune response toward the Th2 type, using intestinal nematode (Trichinella spiralis) infection, on subsequent experimental periodontitis. Methods:Thirty six SPF KM mice were randomly divided into three groups. Periodontitis group: experimental periodontitis was induced by wrapping a 5/0 silk ligature inoculated with putative periodontopathic bacteria around the first maxillary molar. Th2-polaried group: After the mice were infected with low dosage Trichinella spiralis, the experimental periodontitis model was established at that time as above. Mice were sacrificed at the end of 1, 4, 8, 12 weeks. The histological analysis of periodontal tissues was observed by microscope after the samples were stained with hematoxylin and eosin (H&E). The concentrations of IFN--y and IL-4 in mouse serum were determined by ELISA. Results; The results showed that compared with control group Th2-polaried mice had high levels of IL-4 prior nematode infection reduced the severity of periodontitis, and subsequent infection of the periodontium with oral pathogens developed minimal lesions. Few or no osteoclasts were detected in lesions of Th2-polaried group. Conclusion;These results indicate a protective role of nematode infection in Thl cell-driven periodontal damage and prompt consideration of a novel therapeutic strategy in periodontitis based on im-munological distraction.