Prediction and Identification of Epitopes in the Emy162 Antigen of Echinococcus multilocularis

Introduction Alveolar echinococcosis (AE) is a zoonotic disease caused by the parasitism of Echinococcus multilocularis larvae in the intermediate host or the final host. This study aims to identify and analyze the B-cell and T-cell (Th1, Th2 and Th17) epitopes of E. multilocularis antigen Emy162. Methods (1) The secondary structural characteristics of the Emy162 protein were predicted by bioinformatics software to further predict the potential T- and B-cell epitopes. (2) The dominant antigen epitopes were detected by ELISA through the reaction of patient serum with small B-cell antigen peptide and assessing the proliferation of splenic lymphocytes of mice immunized with Emy162. (3) The expression of cytokines in splenic lymphocytes of mice stimulated by small T-cell antigen peptides was detected by ELISA, ELISpot and flow cytometry to enable the identification of the T-cell epitopes. Results (1) The high-scored T-cell epitopes were located at positions E7-13, E36-41, E80-89, E87-96, E97-106 and E129-139, while B-cell epitopes were located at positions E7-13, E19-27, E28-36, E37-48, E78-83, E101-109, E112-121 and E129-139. (2) The three advanced antigen epitopes of Emy162 were E19-27, E112-121 and E129-139. (3) The four Th1 advanced antigen epitopes of Emy162 were E7-13, E36-41, E80-89 and E129-139. The three Th2 advanced antigen epitopes were E36-41, E87-96 and E97-106. The three Th17 advanced antigen epitopes were E36-41, E87-96 and E97-106. Conclusion (1) The Emy162 protein has advanced antigenicity and numerous potential epitopes. Six T-cell and eight B-cell dominant epitopes were revealed using bioinformatics methods. (2) There are three dominant B-cell epitopes, four dominant Th1 epitopes, three dominant Th2 epitopes, and three dominant Th17 epitopes in the Emy162 antigen.