Wang X H, Oon H L, Ho G W P, Wong W S F, Lim T M, Leung K Y
Department of Biological SciencesFaculty of Science University of Singapore,10 Kent Ridge Crescent Singapore 119260.
Department of PharmacologyFaculty of MedicinezNational University of Singapore10 Kent Ridge Crescent Singapore 119260.
Microbiology (Reading). 1998 Nov;144 ( Pt 11):2987-3002. doi: 10.1099/00221287-144-11-2987.
Vibrio anguillarum and Vibrio damselae are Gram-negative bacteria that cause systemic infections called vibriosis in fish. They can enter fish cells and survive as intracellular parasites. The host-pathogen interactions between these Vibrio species and the fish epithelial cell lines epithelioma papillosum of carp (EPC) and grunt-fin tissue (GF) cells, were examined using phase-contrast, scanning electron and confocal microscopy. In addition, potential signal transduction pathways that precede bacterial internalization were studied by using signal transduction inhibitors. Some Vibrio species induced morphological changes in fish cells and this allowed classification into a cytopathic group and a noncytopathic group. The cytopathic group could be subdivided into two invasive groups (I and II) and a cytotoxic group. Of the invasive strains V. anguillarum 811218-5W (group I) and G/Virus/5(3) (group II), genistein, a tyrosine kinase inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3) into EPC cells, whereas staurosporine, a protein kinase C inhibitor, accelerated internalization of both strains. Cytochalasin D, an inhibitor of microfilament polymerization, prevented internalization of both strains, whilst vincristin, a microtubule inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3). For the cytotoxic strain V. damselae ATCC 33539, extracellular products (ECP) alone caused morphological changes in EPC and GF. Bacterial internalization may not be important in the pathogenesis of this group. The non-cytopathic strain V. anguillarum S2/5/93(2) did not enter cells or induce any changes in EPC and GF monolayers. This study has identified some major differences between Vibrio species in their interactions with fish cells in vitro and will thus facilitate future studies of the molecular basis of pathogenesis of vibriosis.
鳗弧菌和美人鱼弧菌是革兰氏阴性菌，可在鱼类中引起称为弧菌病的全身性感染。它们可以进入鱼细胞并作为细胞内寄生虫存活。利用相差显微镜、扫描电子显微镜和共聚焦显微镜研究了这些弧菌属物种与鲤鱼上皮瘤乳头瘤（EPC）和鲷鱼鳍组织（GF）细胞系之间的宿主-病原体相互作用。此外，通过使用信号转导抑制剂研究了细菌内化之前的潜在信号转导途径。一些弧菌属物种会诱导鱼细胞发生形态变化，据此可分为细胞病变组和非细胞病变组。细胞病变组可再细分为两个侵袭组（I和II）和一个细胞毒性组。在侵袭性菌株鳗弧菌811218 - 5W（I组）和G/Virus/5(3)（II组）中，酪氨酸激酶抑制剂染料木黄酮仅抑制鳗弧菌G/Virus/5(3)进入EPC细胞的内化过程，而蛋白激酶C抑制剂星形孢菌素则加速了这两种菌株的内化。微丝聚合抑制剂细胞松弛素D可阻止这两种菌株的内化，而微管抑制剂长春新碱仅抑制鳗弧菌G/Virus/5(3)的内化。对于细胞毒性菌株美人鱼弧菌ATCC 33,539，仅细胞外产物（ECP）就会引起EPC和GF的形态变化。细菌内化在该组的发病机制中可能并不重要。非细胞病变菌株鳗弧菌S2/5/93(2)不会进入细胞，也不会在EPC和GF单层中诱导任何变化。本研究确定了弧菌属物种在体外与鱼细胞相互作用方面的一些主要差异，从而将有助于未来对弧菌病发病机制分子基础的研究。
