梅毒螺旋体Tp92蛋白B细胞表位的预测与鉴定

Prediction and identification of B-cell epitopes of outer membrane protein Tp92 on Treponema pallidum

摘要:

【目的】预测和鉴定梅毒螺旋体(Tp) Tp92蛋白的B细胞表位，为深入探讨这些表位在梅毒表位疫苗中的作用奠定基础。【方法】采用Mobyle、ABCpred和IEDB在线软件综合分析预测Tp92蛋白的B细胞表位，人工合成6条表位多肽，以梅毒患者/感染兔血清(同时设健康人/兔血清对照)为标本，用间接ELISA法鉴定预测Tp92蛋白B细胞表位的免疫反应性。【结果】软件预测显示，Tp92蛋白的P1 (24-39AA)、P2 (332-347AA)、P3 (520-536AA)、P4 (575-588AA)、P5 (103-118AA)、P6 (694-712AA)氨基酸序列可能为其B细胞表位。间接ELISA分析表明，预测的P1、P3、P5和P6均与梅毒患者/感染兔血清呈阳性反应，而与健康人/兔血清不反应。【结论】本研究初步得出以下结论：P1、P3、P5和P6均为Tp92蛋白潜在的特异性B细胞表位，尤其是P3和P6免疫反应性最强。

Abstract:

[Objective] To predict and identify the B-cell epitopes of outer membrane protein Tp92 on Treponema pallidum and provide the basis for further discussion on effects of these epitopes for the epitope-based syphilis vaccine. [Methods] The B-cell epitopes of the protein Tp92 was analyzed with comprehensive meta-analysis Mobyle, ABCpred and IEDB online softwares, and the six peptides containing predicted epitopes were artificially synthesized. The sera from syphilis patients and Tp92-immunized rabbits (normal human and normal rabbits as negative control) were used to determine the immunoreactivity and specificity of six predicted peptides of Tp92 by indirect ELISA. [Results] Comprehensive meta-analysis of online softwares showed that P1 (24-39AA), P2 (332-347AA), P3 (520-536AA), P4 (575-588AA), P5 (103-118AA), and P6 (694-712AA) might be the B-cell epitopes. The result of indirect ELISA indicated that P1、P3、P5 and P6 were active with syphilis patient sera and Tp92-immunized rabbit sera but not with negative control sera. [Conclusion] These results indicate that P1、P3 、P5 and P6 are the potential specific B-cell epitopes, and immunoreactivities of P3 and P6 are the strongest especially.