Prediction and identification of B-cell epitopes of Treponema pallidum repeat protein F / 中国人兽共患病学报

ABSTRACT

To predict and identify the dominant B‐cell epitopes of conserved region of Treponema pallidum repeat protein F (TprFN ) and provide the basis for development of polyvalent epitope‐based syphilis vaccine ,the amino acid sequence of TprFN was obtained from GenBank and analyzed with comprehensive meta‐analysis Mobyle ,ABCpred and IEDB online software .The peptides containing predicted epitopes were artificially synthesized . To obtain and measure the titers of antibodies against TprFN ,New Zealand rabbits were immunized with recombinant protein TprFN expressed in E .coli and identified by Western blot (WB) .Sera from TprFN‐immunized rabbits ,syphilis patients ,and normal human and normal rabbits were used to deter‐mine the immunoreactivity and specificity of 7 predicted peptides of TpFN by indirect ELISA .Comprehensive meta‐analysis of online software showed that P1 (43‐62AA) ,P2(57‐71AA) ,P3(81‐88AA) ,P4(89‐103AA) ,P5(125‐138AA) ,P6(231‐251AA) and P7(268‐279AA) might be the B‐cell epitopes .A protein was expressed in a soluble form and identified as TpFN by WB .The ELISA indicated that P1 and P3 were active with TprFN‐immunized rabbit sera and syphilis patient sera but not with negative control sera .These results indicate that P1 and P3 are the potential dominant B‐cell epitopes .