Bioinformatic prediction and identification of immunogenic epitopes of the antigenic 14-3-3 protein of Echinococcus multilocularis.

Introduction: Alveolar echinococcosis is a high-risk parasitic disease caused by the larval stage of Echinococcus multilocularis. The study aimed to predict and identify the dominant Th1/Th2 and B cell epitopes of the antigen protein 14-3-3 beta:alpha from Echinococcus multilocularis.

Methods: A comparison of the four amino acid sequences of 14-3-3 beta:alpha was respectively derived from Echinococcus multilocularis, Rattus norvegicus, Canis lupus familiaris, and Homo sapiens was carried out by CLUSTALW to provide a basis for excluding similar epitopes. The amino acid sequence information was analyzed by SOPMA and the homology model was established by Swiss-Model. IEDB and SYFPEITHI were used to predict T cell epitopes. According to the Bcepred and ABCpred, the B cell epitopes were comprehensively predicted and analyzed. The dominant epitopes were validated by Lymphocyte Proliferation, ELISA, ELISpot, and Flow cytometry.

Results: Eight potential epitopes of 14-3-3 from Echinococcus multilocularis were screened according to the results of prediction and analysis: 14-3-3, 14-3-3, 14-3-3, 14-3-3, 14-3-3, 14-3-3, 14-3-3, and 14-3-3. The 3D structure model of the protein was constructed and the location distribution of potential epitope was ascertained. Respectively, the epitopes of the dominant antigen of B cells were validated as 14-3-3 and 14-3-3; the Th1 dominant antigen epitopes were 14-3-3, 14-3-3; and the Th2 dominant epitopes was 14-3-3.

Conclusion: In this study, two dominant antigen epitopes of B cells, two Th1 dominant antigen epitopes, and one Th2 dominant antigen epitope were validated. Our work provides a basis for the subsequent development of efficient and safe vaccines targeting epitopes of Echinococcus multilocularis.