The prediction of T- and B-combined epitope of Ag85B antigen of Mycobacterium tuberculosis

After decades of intensive control efforts, tuberculosis (TB) still remains one of the most important causes of morbidity and mortality in the world. Antigen Ag85B, a major protein secreted by Mycobacterium tuberculosis, is a vaccine candidate against TB. In the present study, we used Signalp, TMHMM, ProPred, BIMAS, SYFPEITHI, DNAStar and IEDB to predict the Tand B-cell epitopes. The analysis of the secondary structure and tertiary structure showed that there were five T-cell epitopes and seven B-cell epitopes. Bioinformatics analysis shows the Tand B-combined epitopes. Four Tand B-combined epitopes that triggering both T cell and B cell responses have been predicted. Four Tand B-combined epitopes were synthetic in rAg85B. The recombinant proteins rAg85B were found to have good immunogenicity. The obtained results in the present study may be beneficial in the investigation of rAg85B antigenicity and the development of dominant epitope vaccines.