Nkouawa Agathe, Sako Yasuhito, Nakao Minoru, Nakaya Kazuhiro, Ito Akira
Department of Parasitology, Asahikawa Medical College, Midorigaoka Higashi 2-1-1-1, Asahikawa 078-8510, Hokkaido, Japan.
J Clin Microbiol. 2009 Jan;47(1):168-74. doi: 10.1128/JCM.01573-08. Epub 2008 Nov 12.
Rapid detection and differentiation of Taenia species are required for the control and prevention of taeniasis and cysticercosis in areas where these diseases are endemic. Because of the lower sensitivity and specificity of the conventional diagnosis based on microscopical examination, molecular tools are more reliable for differential diagnosis of these diseases. In this study, we developed and evaluated a loop-mediated isothermal amplification (LAMP) assay for differential diagnosis of infections with Taenia species with cathepsin L-like cysteine peptidase (clp) and cytochrome c oxidase subunit 1 (cox1) genes. LAMP with primer sets to the cox1 gene could differentiate between three species, and LAMP with primer sets to the clp gene could differentiate Taenia solium from Taenia saginata/Taenia asiatica. Restriction enzyme digestion of the LAMP products from primer set Tsag-clp allowed the differentiation of Taenia saginata from Taenia asiatica. We demonstrated the high specificity of LAMP by testing known parasite DNA samples extracted from proglottids (n = 100) and cysticerci (n = 68). LAMP could detect one copy of the target gene or five eggs of T. asiatica and T. saginata per gram of feces, showing sensitivity similar to that of PCR methods. Furthermore, LAMP could detect parasite DNA in all taeniid egg-positive fecal samples (n = 6). Due to the rapid, simple, specific, and sensitive detection of Taenia species, the LAMP assays are valuable tools which might be easily applicable for the control and prevention of taeniasis and cysticercosis in countries where these diseases are endemic.
在绦虫病和囊尾蚴病的流行地区,为了控制和预防这些疾病,需要快速检测和区分绦虫种类。由于基于显微镜检查的传统诊断方法敏感性和特异性较低,分子工具对于这些疾病的鉴别诊断更为可靠。在本研究中,我们开发并评估了一种环介导等温扩增(LAMP)检测方法,用于鉴别感染了具有组织蛋白酶L样半胱氨酸蛋白酶(clp)和细胞色素c氧化酶亚基1(cox1)基因的绦虫种类。针对cox1基因的引物组进行LAMP检测可以区分三种绦虫,针对clp基因的引物组进行LAMP检测可以区分猪带绦虫与牛带绦虫/亚洲带绦虫。对来自引物组Tsag-clp的LAMP产物进行限制性内切酶消化,可以区分牛带绦虫和亚洲带绦虫。我们通过检测从节片(n = 100)和囊尾蚴(n = 68)中提取的已知寄生虫DNA样本,证明了LAMP的高特异性。LAMP能够检测到每克粪便中一个拷贝的靶基因或五个亚洲带绦虫和牛带绦虫虫卵,其灵敏度与PCR方法相似。此外,LAMP能够检测所有带绦虫卵阳性粪便样本(n = 6)中的寄生虫DNA。由于LAMP检测方法能够快速、简便、特异且灵敏地检测绦虫种类,它是一种有价值的工具,可能很容易应用于这些疾病流行国家的绦虫病和囊尾蚴病的控制和预防。