鼻咽癌Epstein－Barr病毒受体（EBVR／CR＿2）基因的病毒结合区的序列测定

DNA SFQUENCING OF THE EPSTEIN-BARR VIRUS BINDINGSITE OF EBVR/CR_2 GENE IN NASOPHARYNGEAL CARCINOMA

Ｅｐｓｔｅｉｎ－Ｂａｒｒ病毒（ＥＢＶ）进入鼻咽上皮细胞的途径，是人们研究ＥＢＶ与鼻咽癌（ＮＰＣ）的病因关系时所必须回答的一个问题。用抗ＥＢＶ受体（ＥＢＶＲ／ＣＲ＿２）单抗检测上皮细胞中该受体的表达已有报道，但对上皮细胞中ＥＢＶＲ／ＣＲ＿２的基因结构仍需研究。我们采用ＰＣＲ扩增和不对称ＰＣＲ直接测序法，首次检测了１０例ＮＰＣ及３例正常人胚鼻咽上皮（Ｈｕｍａｎｅｍｂｒｙｏｎｉｃｎａｓｏｐａｒｙｎｇｅａｌｅｐｉｔｈｅｌｉｕｍ，ＨＥＮＥ）组织样本中ＥＢＶＲ／ＣＲ＿２的ＥＢＶ结合区的编码序列。这一片段的ＤＮＡ序列测定结果显示，人ＮＰＣ细胞和正常ＨＥＮＥ细胞的ＥＢＶＲ／ＣＲ＿２的ＥＢＶ结合区的编码序列，与正常人Ｂ淋巴细胞的ＥＢＶＲ／ＣＲ＿２的相应序列完全相同，提示ＥＢＶ感染鼻咽上皮细胞可能与ＥＢＶＲ／ＣＲ＿２基因的ＥＢＶ结合区结构改变无直接关系。

ow Epstein-Barr virus enters nasopharyngeal epithelial cells is an essential question inunderstanding the pathogenitic relationship between EBV and nasopharyngeal carnicoma(NPC)Although there were some reports about the expression of EBV receptor (EBVR/CR_2) onepithelial cells using monoclonal antibodies against EBVR/CR_2, there were no reports on thestructural analysis of EBVR/CR_2 gene in epithelial cells. Here, we amplified the encodingregion of EBV binding site SCR_11 and SCR_2 (short consensus repeat) of EBVR/CR_2 by PCR(polymerase chain reaction) and performed DNA sequencing by asymmetric PCR method in 10cases of NPC samples and 3 cases of normal human embryonic-nasopharyngeal epithelial(HENE) cells. A 380 bp product was obtained after amplification. DNA sequencing of thisregion showed that the sequence of EBV binding site SCR_1 and SCR_2 of EBVR/CR_2 inhuman NPC cells and HENE cells was just the same as that of the nomal human Blymphocytes.The result suggests that there might be no direct relationship between EBV infection andthe change of EBV binding site of EBV receptor gene and this provides an experimentalevidenee for further studying the expression of EBV receptor.