Gottstein B
Parasite Immunol. 1985 May;7(3):201-12. doi: 10.1111/j.1365-3024.1985.tb00070.x.
A polypeptide (Em2a) purified by affinity chromatography from the Echinococcus multilocularis metacestode showed a high degree of purity as assayed by SDS-PAGE and analytical isoelectrical focusing. A minor contamination with host albumin was revealed. Estimation of relative mol. mass gave a value of 54,000. The isoelectric point was found to be 4.8. Antigenic activity of the polypeptide was demonstrated by immunoprecipitation and western blotting. In these assays the protein was recognized only by homologous sera from patients infected with larval E. multilocularis. This antigen (Em2a) did not react in the ELISA with sera from patients infected with heterologous helminths; these sera were highly cross-reacting with antigen from E. granulosus hydatid fluid. Seventy-three (94%) from 78 investigated patients (alveolar echinococcosis) showed a seropositive reaction with the polypeptide Em2a.
通过亲和层析从多房棘球绦虫幼虫中纯化得到的一种多肽（Em2a），经SDS - PAGE和分析性等电聚焦检测显示具有高度纯度。检测发现有少量宿主白蛋白污染。相对分子质量估计值为54,000。等电点为4.8。通过免疫沉淀和western印迹证实了该多肽的抗原活性。在这些检测中，该蛋白仅被感染多房棘球绦虫幼虫的患者的同源血清识别。这种抗原（Em2a）在ELISA中不与感染异源蠕虫患者的血清发生反应；这些血清与细粒棘球绦虫囊液抗原高度交叉反应。78例接受调查的患者（肺泡型棘球蚴病）中有73例（94%）与多肽Em2a呈血清阳性反应。
