Kramer L H, Passeri B, Corona S, Simoncini L, Casiraghi M
Dept. of Animal Production,Veterinary Biotechnology and Food Safety, University of Parma, Via del Taglio 8, 43100 Parma, Italy.
Parasitol Res. 2003 Mar;89(5):381-6. doi: 10.1007/s00436-002-0765-6. Epub 2002 Nov 30.
Intracellular bacteria in filarial nematodes were described as early as the 1970s, yet it was only with the work on Dirofilaria immitis, the agent of canine and feline heartworm disease, that these microorganisms were identified as belonging to Wolbachia, a genus known for encompassing bacteria infecting insects and other arthropods. The implications for the presence of intracellular bacteria in filarial nematodes is now the subject of intense research, particularly regarding their role in the immunology and pathogenesis of disease in infected humans and animals and as a possible target for therapy. Here, the authors report results on the immunohistochemical and immunogold staining of Wolbachia in D. immitis and Brugia pahangi using polyclonal antibodies raised against the recombinant Wolbachia surface protein (WSP). The bacteria were present in the lateral hypodermal chords of both male and female worms and in the reproductive tract of adult females (oocytes, morulae, microfilariae). In D. immitis and B. pahangi from animals treated with tetracycline, positive staining was observed in the lateral chords of adult males and females, but was absent from the oocytes and morulae. These results indicate that Wolbachia endosymbionts can be identified immunohistochemically with anti-WSP polyclonal antibodies, that their distribution matches that already described for Wolbachia of other filarial worms, and that antibiotic treatment may impede the vertical transmission of these bacteria. Unequivocal detection of Wolbachia is essential for the study of this symbiont, in particular to monitor the effects of antibiotic treatment on worms. The use of a specific marker for bacteria in their nematode hosts represents an extremely useful tool in evaluating the pathogenic role and the effect of antibiotic treatment on these potential targets in the control of filarial disease.
早在20世纪70年代就有人描述过丝虫线虫体内的细胞内细菌，但直到对犬心丝虫病和猫心丝虫病的病原体——犬恶丝虫进行研究时，这些微生物才被鉴定为属于沃尔巴克氏体属，该属以包含感染昆虫和其他节肢动物的细菌而闻名。丝虫线虫体内存在细胞内细菌的意义现在是深入研究的课题，特别是关于它们在受感染的人类和动物疾病的免疫学和发病机制中的作用以及作为一种可能的治疗靶点。在此，作者报告了使用针对重组沃尔巴克氏体表面蛋白（WSP）产生的多克隆抗体对犬恶丝虫和班氏吴策线虫中的沃尔巴克氏体进行免疫组织化学和免疫金染色的结果。这些细菌存在于雄虫和雌虫的侧皮下索以及成年雌虫的生殖道（卵母细胞、桑椹胚、微丝蚴）中。在用四环素治疗的动物的犬恶丝虫和班氏吴策线虫中，在成年雄虫和雌虫的侧索中观察到阳性染色，但在卵母细胞和桑椹胚中没有。这些结果表明，沃尔巴克氏体共生菌可以用抗WSP多克隆抗体进行免疫组织化学鉴定，它们的分布与已描述的其他丝虫的沃尔巴克氏体的分布相匹配，并且抗生素治疗可能会阻碍这些细菌的垂直传播。对沃尔巴克氏体进行明确检测对于研究这种共生菌至关重要，特别是为了监测抗生素治疗对虫体的影响。在其线虫宿主中使用细菌的特异性标记物是评估这些潜在靶点在丝虫病控制中的致病作用和抗生素治疗效果的极其有用的工具。
