Mombelli A, Gmür R, Lang N P, Corbert E, Frey J
School of Dental Medicine, University of Bern, Switzerland.
J Clin Periodontol. 1999 Aug;26(8):505-10. doi: 10.1034/j.1600-051x.1999.260803.x.
The aim of the present study was to examine the Actinobacillus actinomycetemcomitans carrier rate in Chinese subjects, and to determine serotype distribution, presence of the leukotoxin gene lktA and the structure of the lktA-promoter region. Subgingival microbiological samples were obtained from 31 Chinese subjects with moderate to advanced adult periodontitis, 73 young factory workers, and 81 adult residents of a rural area. Bacterial isolates phenotypically identified as A. actinomycetemcomitans were found in 116 of the 185 subjects (detection frequency over-all: 63%). Presence of the leukotoxin gene lktA was demonstrated for all 115 isolates that could be subcultured. The PCR analysis of the lktA-promoter region showed that none of these strains had the deletion in the promoter region known to enhance expression of lktA. No significant difference in the frequency of A. actinomycetemcomitans could be observed between the subjects of the 3 study groups. Analysis by logistic multiple regression indicated a homogeneous distribution of A. actinomycetemcomitans in the 3 cohorts and a lack of significant influence of subject gender or age. Serotype a was found in 21 subjects, serotype b was found in 9, serotype c in 67 and serotype e in 11 individuals. Serotype d was not detected in any subject. Nontypeable isolates, lacking serotype a, b, c, d, or e antigens, were found in 9 individuals. A high prevalence irrespective of gender, age, and cohort suggests that A. actinomycetemcomitans is a common constituent of the normal flora in the Chinese subjects of this study and suggests differences in the microbiological composition of subgingival plaque may exist for this population group as compared to north American and European populations.
本研究的目的是检测中国受试者中伴放线放线杆菌的携带率，确定血清型分布、白细胞毒素基因lktA的存在情况以及lktA启动子区域的结构。从31名患有中度至重度成人牙周炎的中国受试者、73名年轻工厂工人和81名农村成年居民中获取龈下微生物样本。在185名受试者中的116名中发现了表型鉴定为伴放线放线杆菌的细菌分离株（总体检测频率：63%）。在所有115株可传代培养的分离株中均证实存在白细胞毒素基因lktA。lktA启动子区域的PCR分析表明，这些菌株中没有一株在已知可增强lktA表达的启动子区域存在缺失。在3个研究组的受试者之间，伴放线放线杆菌的频率没有显著差异。逻辑多元回归分析表明，伴放线放线杆菌在3个队列中分布均匀，受试者的性别或年龄没有显著影响。在21名受试者中发现血清型a，9名中发现血清型b，67名中发现血清型c，11名中发现血清型e。在任何受试者中均未检测到血清型d。在9名个体中发现了缺乏血清型a、b、c、d或e抗原的不可分型分离株。无论性别、年龄和队列如何，高流行率表明伴放线放线杆菌是本研究中中国受试者正常菌群的常见组成部分，并且表明与北美和欧洲人群相比，该人群组龈下菌斑的微生物组成可能存在差异。
