Analysis of protoscoleces-specific antigens from Echinococcus granulosus with proteomics combined with Western blot.

OBJECTIVE: To establish and optimize the proteomic analysis of protoscoleces-specific antigens from Echinococcus granulosus. To provide a foundation for identifying specific antigens in the soluble proteins of E. granulosus protoscoleces for further research. METHODS: Brood capsules were collected aseptically from fertile E. granulosus cysts from the livers of an infected patient. The fertile E. granulosus cysts were fractured, and protoscoleces were collected by centrifugation. The soluble proteins of protoscoleces were acquired using the 2D Quant kit according to the manufacturer's instructions. We employed two-dimensional electrophoresis (2-DE) combined with immunoblot assay (Western blot) to analyze the soluble components of E. granulosus protoscoleces antigens. The 2-DE and immunoblot maps obtained were analyzed with PDQuest 8.0 image analysis software. RESULTS: About 233 soluble protein spots were identified with Coomassie-stained gels. Most of the proteins had a molecular weight of 16,000 Da to 117,000 Da, and an isoelectric point value of 3.0 to 10.0. 2-DE immunoblot was conducted and 57 specific antigen spots were observed, among which 23 spots were identified. CONCLUSION: 2-DE combined with Western blot is the key to successful proteomic analysis and presents a new possibility for searching the specific E. granulosus protoscoleces antigens.