免疫低下豚鼠伴放线放线杆菌和牙龈卟啉单胞菌感染特征

Infection Characters of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in Immunodeficient Guinea Pigs

目的 研究免疫低下对青少年牙周炎 (JP)特异性病原菌感染的影响。方法 二次6 0 Co全身照射制备免疫低下豚鼠及正常豚鼠各 36只 ,随机分组 ,下前牙龈沟接种伴放线放线杆菌 (Aa)和 或牙龈卟啉单胞菌 (Pg) ,于 2、3、6周分批处死 ,进行组织病理学及破骨细胞计数对比研究。结果 免疫低下Aa、Pg、Aa +Pg组 2、3周时牙周破坏明显 ,重于免疫正常组 ,破骨细胞计数高于免疫正常组 ,有统计学差异 (P <0 0 5 )。结论 免疫低下加重Aa、Pg对牙周组织破坏 ,机体免疫状态是JP发生发展的重要环节。

Objective\ The aim of this study was to investigate effects of immunodeficiency on the periodontal infection characters of the specific pathogens of juvenile periodontitis.Methods\ A total of 36 immunodeficient guinea pigs produced by twice whole_body irradiation with \+\{60\}Co were divided randomly into four groups, in which Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and A.actinomycetemcomitans with P.gingivalis were inoculated into the gingival sulcus of two mandibular incisors respectively. The pigs in the control group did not receive any inoculation. At 2, 3 and 6 weeks after inoculation, three animals in each group were sacrificed successively. Clinical and histological examinations were used to examine the changes in the periodontal tissues. The other 36 normal guinea pigs were divided into four groups and treated in a similar way described above.Results\ Significant periodontal damages were noted in immunodeficient pigs inoculated with A. actinomycetemcomitans, P. gingivalis or A. actinomycetemcomitans and P.gingivalis in 2 and 3 weeks after bacterial inoculation. The damages were more severe than in the normal groups. The immunodeficient groups demonstrated larger numbers of osteoclasts than the normal groups (P<0.05).Conclusion\ The loss of periodontal tissue in immunodeficient hosts is much serious than those with normal defence system, after they are infected with A.actinomycetemcomitans and P.gingivalis. Abnormal defence system in hosts may play an important role in onset and development of juvenile periodontitis.