Hawdon J M
Medical Helminthology Laboratory, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
J Parasitol. 1996 Aug;82(4):642-7.
There are 2 major species of hookworms that infect humans. Ancylostoma duodenale and Necator americanus. Although traditionally considered to be identical for treatment purposes, there are significant life history differences between the species that must be considered for the rational design of chemotherapeutic and immunoprophylactic control strategies. However, identification of the species infecting a particular population has been problematic, as the eggs of the 2 species cannot be reliably differentiated by classical parasitological methods. A PCR-based technique for the differentiation of hookworm species that infect humans is reported. A fragment of the 3' untranslated region of the cAMP-dependent protein kinase catalytic subunit gene was amplified from A. duodenale and N. americanus genomic DNA using primers derived from the corresponding A. caninum cDNA. Digestion of the amplified DNA with the restriction enzymes HpaII, MboI, TaqI, and ThaI generated specific restriction fragment patterns unique to each species. The technique can distinguish between pure and mixtures of hookworm DNA and can amplify DNA from a single egg. The primers also amplify the fragment from the DNA of several other species of hookworms that infect humans and other animals. The technique is fast, simple, and hookworm specific and represents a considerable savings in time over current methods used for distinguishing between human hookworm infections.
有两种主要的感染人类的钩虫。十二指肠钩口线虫和美洲板口线虫。尽管传统上认为在治疗方面二者相同，但这两个物种之间存在显著的生活史差异，在合理设计化疗和免疫预防控制策略时必须予以考虑。然而，确定感染特定人群的钩虫种类一直存在问题，因为这两种钩虫的虫卵无法通过传统寄生虫学方法可靠地区分。本文报道了一种基于聚合酶链反应（PCR）的区分感染人类钩虫种类的技术。使用源自犬钩虫相应互补DNA（cDNA）的引物，从十二指肠钩口线虫和美洲板口线虫的基因组DNA中扩增出环磷酸腺苷（cAMP）依赖性蛋白激酶催化亚基基因3'非翻译区的一个片段。用限制性内切酶HpaII、MboI、TaqI和ThaI消化扩增的DNA，产生了每个物种特有的特定限制性片段模式。该技术可以区分钩虫DNA的纯品和混合物，并且可以从单个虫卵中扩增DNA。这些引物还能从感染人类和其他动物的其他几种钩虫的DNA中扩增出该片段。该技术快速、简单且具有钩虫特异性，与目前用于区分人类钩虫感染的方法相比，可节省大量时间。
