Inaba H, Nakano K, Kato T, Nomura R, Kawai S, Kuboniwa M, Ishihara K, Ooshima T, Amano A
Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan.
Oral Microbiol Immunol. 2008 Feb;23(1):29-35. doi: 10.1111/j.1399-302X.2007.00386.x.
BACKGROUND/AIMS: Porphyromonas gingivalis is a periodontal pathogen whose fimbriae are classified into six genotypes (types I-V and Ib) based on the diversity of the fimA genes encoding the fimbrial subunits. Accumulated evidence suggests that P. gingivalis strains with type II fimbriae are more virulent as compared to those with other types. However, it is unknown if strong virulence is uniformly conserved among clones with type II fimbriae. In the present study, we compared infectious inflammatory changes in clinical isolates of P. gingivalis with type II fimbriae using a mouse abscess model to examine their pathogenic heterogeneity and heterogeneity-related factors.
Suspensions of nine different clinical isolates with type II fimbriae were subcutaneously injected into female BALB/c mice and inflammatory parameters, such as serum sialic acid concentration, were compared.
Many of the type II fimbrial isolates caused severe inflammation in the mice, though some were less causative, as was the control strain ATCC 33277 (type I fimbria strain). These results showed that pathogenic heterogeneity exists among P. gingivalis clones with type II fimbriae. Further, the heterogeneity-related factors of P. gingivalis strains were analyzed and the pathogenic potentials showed positive relationships to gingipain activities and invasive efficiency but not to hydrophobicity or autoaggregation. In addition, invasive efficiency was related to the activities of gingipains that were extracellularly secreted.
These results suggest that pathogenic heterogeneity has relationships with the invasive and proteolytic activities of P. gingivalis clones with type II fimbriae.
背景/目的：牙龈卟啉单胞菌是一种牙周病原体，其菌毛根据编码菌毛亚基的fimA基因的多样性分为六种基因型（I-V型和Ib型）。越来越多的证据表明，与其他类型的菌株相比，具有II型菌毛的牙龈卟啉单胞菌菌株更具毒性。然而，尚不清楚具有II型菌毛的克隆中强大的毒性是否一致保守。在本研究中，我们使用小鼠脓肿模型比较了具有II型菌毛的牙龈卟啉单胞菌临床分离株的感染性炎症变化，以检查它们的致病异质性和与异质性相关的因素。
将九种不同的具有II型菌毛的临床分离株的悬液皮下注射到雌性BALB/c小鼠体内，并比较炎症参数，如血清唾液酸浓度。
许多具有II型菌毛的分离株在小鼠中引起严重炎症，尽管有些分离株的致病性较低，对照菌株ATCC 33277（I型菌毛菌株）也是如此。这些结果表明，具有II型菌毛的牙龈卟啉单胞菌克隆之间存在致病异质性。此外，分析了牙龈卟啉单胞菌菌株与异质性相关的因素，其致病潜力与牙龈蛋白酶活性和侵袭效率呈正相关，但与疏水性或自聚集无关。此外，侵袭效率与细胞外分泌的牙龈蛋白酶的活性有关。
这些结果表明，致病异质性与具有II型菌毛的牙龈卟啉单胞菌克隆的侵袭和蛋白水解活性有关。
