Bassinet L, Gueirard P, Maitre B, Housset B, Gounon P, Guiso N
Laboratoire des Bordetella, Institut Pasteur, Paris, France.
Infect Immun. 2000 Apr;68(4):1934-41. doi: 10.1128/IAI.68.4.1934-1941.2000.
Bordetella pertussis, the agent of whooping cough, can invade and survive in several types of eukaryotic cell, including CHO, HeLa 229, and HEp-2 cells and macrophages. In this study, we analyzed bacterial invasiveness in nonrespiratory human HeLa epithelial cells and human HTE and HAE0 tracheal epithelial cells. Invasion assays and transmission electron microscopy analysis showed that B. pertussis strains invaded and survived, without multiplying, in HTE or HAE0 cells. This phenomenon was bvg regulated, but invasive properties differed between B. pertussis strains and isolates and the B. pertussis reference strain. Studies with B. pertussis mutant strains demonstrated that filamentous hemagglutinin, the major adhesin, was involved in the invasion of human tracheal epithelial cells by bacteria but not in that of HeLa cells. Fimbriae and pertussis toxin were not found to be involved. However, we found that the production of adenylate cyclase-hemolysin prevents the invasion of HeLa and HTE cells by B. pertussis because an adenylate cyclase-hemolysin-deficient mutant was found to be more invasive than the parental strain. The effect of adenylate cyclase-hemolysin was mediated by an increase in the cyclic AMP concentration in the cells. Pertactin (PRN), an adhesin, significantly inhibited the invasion of HTE cells by bacteria, probably via its interaction with adenylate cyclase-hemolysin. Isolates producing different PRNs were taken up similarly, indicating that the differences in the sequences of the PRNs produced by these isolates do not affect invasion. We concluded that filamentous hemagglutinin production favored invasion of human tracheal cells but that adenylate cyclase-hemolysin and PRN production significantly inhibited this process.
百日咳博德特氏菌是百日咳的病原体，可在多种真核细胞中侵袭并存活，包括中国仓鼠卵巢细胞（CHO）、海拉229细胞、人喉表皮样癌细胞（HEp-2）以及巨噬细胞。在本研究中，我们分析了该细菌在非呼吸道的人源海拉上皮细胞以及人源HTE和HAE0气管上皮细胞中的侵袭能力。侵袭试验和透射电子显微镜分析表明，百日咳博德特氏菌菌株可在HTE或HAE0细胞中侵袭并存活，但不繁殖。这种现象受bvg调控，但百日咳博德特氏菌菌株、分离株与百日咳博德特氏菌参考菌株的侵袭特性有所不同。对百日咳博德特氏菌突变株的研究表明，主要黏附素丝状血凝素参与了细菌对人气管上皮细胞的侵袭，但不参与对海拉细胞的侵袭。未发现菌毛和百日咳毒素参与其中。然而，我们发现腺苷酸环化酶溶血素的产生会阻止百日咳博德特氏菌对海拉细胞和HTE细胞的侵袭，因为发现一株腺苷酸环化酶溶血素缺陷型突变株比亲本菌株更具侵袭性。腺苷酸环化酶溶血素的作用是通过细胞内环磷酸腺苷（cAMP）浓度的升高介导的。黏附素百日咳杆菌黏附素（PRN）可能通过与腺苷酸环化酶溶血素相互作用，显著抑制了细菌对HTE细胞的侵袭。产生不同PRN的分离株被摄取的情况相似，这表明这些分离株产生的PRN序列差异不影响侵袭。我们得出结论，丝状血凝素的产生有利于对人气管细胞的侵袭，但腺苷酸环化酶溶血素和PRN的产生则显著抑制了这一过程。
