The Cytolethal Distending Toxin of Haemophilus ducreyi Inhibits Endothelial Cell Proliferation

Haemophilus ducreyi, the etiologic agent of the sexually transmitted disease chancroid, produces a cytolethal distending toxin (HdCDT) that inhibits mammalian cell proliferation. We investigated the effects of HdCDT on normal human endothelial cells and on tubule formation in an in vitro model of angiogenesis. Endothelial cells were arrested in the G(2) phase of the cell cycle, and tubule formation was inhibited in a dose-dependent manner. The antiproliferative activities of HdCDT on endothelial cells might contribute to the characteristic slow healing and persistence of chancroid ulcers.

杜克雷嗜血杆菌（Haemophilus ducreyi）是性传播疾病软下疳的致病病原体，可分泌细胞致死膨胀毒素（HdCDT），该毒素能够抑制哺乳动物细胞增殖。本研究探究了HdCDT对正常人内皮细胞的作用，以及其在血管生成体外模型中对管腔形成的影响。实验结果显示，内皮细胞被阻滞于细胞周期的G2期，管腔形成呈现剂量依赖性抑制。HdCDT对内皮细胞的抗增殖活性，或可解释软下疳溃疡典型的愈合缓慢与持续存在的病理特征。