B and T-Cell Epitope Prediction of the OMP25 Antigen for Developing Brucella melitensis Vaccines for Sheep

Brucellosis, produced by Brucella species, is a disease that causes severe economic losses for livestock farms worldwide Due to serious economic and medical consequences of this disease, many efforts have been made to prevent the infection through the use of recombinant vaccines based on Brucella outer membrane protein (OMP) antigens. In the present study, a wide range of on-line prediction software was used to predict B and T-cells epitopes, secondary and tertiary structure and antigenicity OMP25 antigens. The bioinformatics approach used in the present study was validated by comparing its results with four available experimental epitope predictions. Bioinformatics analysis identified B-cell epitopes locations at amino acid (AA) residues 26-44, 59-79, 88-112, 146-166 and 175-202l and T-cell epitopes at AA residues 1-10, 14-22, 122-132, 154-162 and 206-213. All final B and T-cell predicted epitopes, except 1-10 and 14-22 residuals, showed antigenicity ability. Finally, a common B and T-cell epitope was identified at 154-162 of the OMP25 antigen. Bioinformatics analysis showed that this region has proper epitope characterization and so may be useful for producing recombinant vaccine.