Hemmings L, McManus D P
Department of Pure and Applied Biology, Imperial College of Science and Technology, London, U.K.
Mol Biochem Parasitol. 1989 Mar 1;33(2):171-82. doi: 10.1016/0166-6851(89)90031-5.
A lambda gt11 cDNA expression library consisting of a million recombinant clones has been constructed from Echinococcus multilocularis protoscolex mRNA. Differential screening of the library with pools of E. multilocularis and Echinococcus granulosus human infection sera has revealed 13 potentially immunodiagnostic clones. On the basis of plaque immunoassays and lysogen characteristics, two of these clones, designated EM2 and EM4, have been further characterised. The recombinant fusion-peptides have been purified and their potential as immunodiagnostic reagents has been assessed by immunoblotting and, in the case of one fusion-peptide (EM4), by enzyme-linked immunosorbent assay (ELISA). Furthermore, the native parasite antigens coded for by these clones have been identified. EM2 corresponds to a 70 kDa protein and epitopes coded for by EM4 have been found on three antigens of 62, 49 and 44 kDa. The native antigens of both clones are present in the protoscolex and those corresponding to EM4 appear to be excreted/secreted products. They are not recognised in ELISA by a variety of human parasitic infection sera other than sera taken from patients infected with E. multilocularis. Nevertheless, the native antigens for both clones are present in E. granulosus protoscoleces and Taenia solium cysticerci. These antigens are not detectable in E. granulosus cyst fluid, and this may, in part, explain the lack of immune response to them in human E. granulosus and T. solium infections.
已从多房棘球绦虫原头蚴mRNA构建了一个由100万个重组克隆组成的λgt11 cDNA表达文库。用多房棘球绦虫和细粒棘球绦虫人类感染血清池对该文库进行差异筛选，发现了13个潜在的免疫诊断克隆。基于噬菌斑免疫测定和溶原特性，其中两个克隆，命名为EM2和EM4，已得到进一步鉴定。重组融合肽已被纯化，其作为免疫诊断试剂的潜力已通过免疫印迹进行评估，对于一种融合肽（EM4），还通过酶联免疫吸附测定（ELISA）进行了评估。此外，已鉴定出这些克隆编码的天然寄生虫抗原。EM2对应于一种70 kDa的蛋白质，并且在62、49和44 kDa的三种抗原上发现了EM4编码的表位。两个克隆的天然抗原都存在于原头蚴中，与EM4对应的那些抗原似乎是排泄/分泌产物。除了来自多房棘球绦虫感染患者的血清外，它们在ELISA中不被多种人类寄生虫感染血清识别。然而，两个克隆的天然抗原都存在于细粒棘球绦虫原头蚴和猪带绦虫囊尾蚴中。这些抗原在细粒棘球绦虫囊液中无法检测到，这可能部分解释了人类细粒棘球绦虫和猪带绦虫感染中对它们缺乏免疫反应的原因。
