A comparison of Chryseobacterium indologenes pathogenicity to the soft tick Ornithodoros moubata and hard tick Ixodes ricinus
A comparison of Chryseobacterium indologenes pathogenicity to the soft tick Ornithodoros moubata and hard tick Ixodes ricinus
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DOI：
10.1016/j.jip.2006.05.006
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发表时间：
2006-10-01
影响因子：
3.4
通讯作者：
Kopacek, Petr
中科院分区：
文献类型：
--
作者：
Buresova, Veronika;Franta, Zdenek;Kopacek, Petr
在濒临死亡的实验室菌落中，约 65% 的毛白钝缘蜱软蜱的肠道内容物中发现了一种黄色革兰氏阴性细菌，即金黄杆菌。分离的推定病原体 C. indologenes 对复方新诺明敏感，在血粉中添加这种抗生素 (Biseptol 480) 可显着降低蜱死亡率。通过膜喂养被吲哚氏梭菌污染的血液而对健康的毛白蜱进行人工感染，在浓度 >= 10(6) 个细菌/ml 时对所有蜱均致死。相反，通过毛细管喂养对硬蜱蓖麻硬蜱施加相似的感染剂量并没有导致显着的死亡率。对从受感染的 O. moubata 和 I. ricinus 中解剖的肠道进行检查后发现，C. indologenes 在软蜱中呈指数倍增，但在 1 天内从硬蜱的肠道中完全清除。在这两种蜱种中，发现 C. indologenes 从肠道渗透到血腔中。通过血腔内显微注射吲哚氏梭菌来测试两种蜱种血细胞的吞噬活性，并使用针对全细菌产生的抗体通过间接荧光显微镜进行评估。两种蜱种的血细胞均表现出显着的针对 C indologenes 的吞噬活性。注射C. indologenes的毛白芥在3天内全部死亡，而注射蓖麻的死亡率增加并不显着。我们的结果表明，硬蜱具有比软蜱更有效的防御系统来抵抗 C. indologenes 感染。因此，C. indologenes 感染有可能成为研究蜱对传播病原体的免疫反应的相关比较模型。 (c) 2006 Elsevier Inc. 保留所有权利。
A yellow-pigmented Gram-negative bacterium, Chryseobacterium indologenes, was found in the gut contents of about 65% of soft ticks Ornithodoros moubata from a perishing laboratory colony. The isolated putative pathogen, C. indologenes, was susceptible to cotrimoxazol and addition of this antibiotic (Biseptol 480) to the blood meal significantly decreased the tick mortality rate. The artificial infection of healthy O. moubata by membrane feeding on blood contaminated with C. indologenes was lethal to all ticks at concentrations >= 10(6) bacteria/ml. On the contrary, a similar infection dose applied to the hard tick Ixodes ricinus by capillary feeding did not cause significant mortality. Examination of guts dissected from infected O. moubata and I. ricinus revealed that C. indologenes was exponentially multiplied in the soft tick but were completely cleared from the gut of the hard ticks within 1 day. In both tick species, C. indologenes were found to penetrate from the gut into the hemocoel. The phagocytic activity of hemocytes from both tick species was tested by intrahaemocoelic microinjection of C. indologenes and evaluated by indirect fluorescent microscopy using antibodies raised against whole bacteria. Hemocytes from both tick species displayed significant phagocytic activity against C indologenes. All O. moubata injected with C. indologenes died within 3 days, whereas the increase of the mortality rate of I. ricinus was insignificant. Our results indicate that hard ticks possess much more efficient defense system against infection with C. indologenes than the soft ticks. Thus, C. indologenes infection has the potential to be a relevant comparative model for the study of tick immune reactions to transmitted pathogens. (c) 2006 Elsevier Inc. All rights reserved.