汉滩病毒S基因的分段表达及其线性和构象型抗原表位分析

构建汉滩病毒76—118N蛋白及其分别从N-端和C-端缺失的共6个突变体，在大肠杆菌BL-21中进行表达，并对其中一些蛋白进行了纯化。通过Western blot、酶联免疫吸附试验(ELISA)进行汉滩病毒N蛋白的抗原表位分析，N蛋白及6个缺失突变体都与组特异性抗体L13F3呈阳性反应，而缺失突变体与型特异性抗体AH30呈阴性反应。构建汉滩病毒76—118N蛋白及其6个缺失突变体的真核表达载体，并在COS-7细胞中进行表达。通过间接免疫荧光试验(IFA)进行汉滩病毒N蛋白的抗原表位分析，病人血清与真核表达的N蛋白及6个缺失突变体呈阳性反应。而仅有N蛋白及缺失N端1～30位氨基酸序列的NPN30与型特异性抗体AH30呈阳性反应。证实组特异性抗体L13F3结合的抗原表位位于N端1～30位氨基酸；而C端抗原表位对于型特异性抗体AH30与N蛋白的识别和结合具有重要意义，缺失N端100位氨基酸序列可能破坏羧基端构象型表位，也可以影响N蛋白与AH30的结合。

Analysis of the Liner and Conformational Epitopes of Hantaan virus N Protein

The S gene of hantaan virus (HTNV) was fragmentally truncated and expressed in E.coli and COS-7 cells. The full N protein and the truncated N proteins with C- terminal series deletion were reacted with hantavirus group specific monoclonal antibody(McAb) L13F3. The truncated N proteins with N-terminal deletion at the position of 1-30 and 1-100 amino acid(aa)lost the reactivity with L13F3. On the contrast, the 1-30aa N-terminal truncated HTNV N protein reacted with the HTNV specific human antibody AH30 in non-denatured form but not in denatured form. The results suggested that group specific antigenic epitope on HTNV N protein is liner epitope, located in the N-terminal of N protein and type specific antigenic epitope is conformational epitope, distributed at C-terminal of N protein. The epitope on the N protein recognized by group specific McAb L13F3 located at 1-30 amino acids of the N-terminus of N protein. C-terminal 50aa plays important role in consisting of a conformational epitope on the HTNV N protein recognized by the type specific antibody AH30. The binding ability of type specific McAb with HTNV N protein was also influenced by N-terminal epitopes behind amino acid 100 and may contribute to the formation of the conformational epitope.