摘要
目的研究外周血单个核细胞（ＰＢＭＣ）中乙型肝炎病毒（ＨＢＶ）包膜抗原基因变异的意义。方法收集１９例慢性乙肝患者的ＰＢＭＣ和配对血清，用ＰＣＲ扩增ＰＢＭＣ及血清中ＨＢＶ包膜基因片段（Ｓ，ｐｒｅＳ１，ｐｒｅＳ２），并对其中各５例ＰＢＭＣ及配对血清中的ｐｒｅＳ１和ｐｒｅＳ２基因片段，分别进行核苷酸序列分析。结果Ｓ、ｐｒｅＳ１和ｐｒｅＳ２片段在血清和ＰＢＭＣ中的检出率，分别为１００％、９４７％、１００％和０、２６３％、２６３％。与ＨＢＶＡＤＲ序列比较，１０份标本ＨＢＶＤＮＡ核苷酸序列分析，发现２份ｐｒｅＳ１和３份ｐｒｅＳ２的核苷酸序列，没有发生改变；８份ｐｒｅＳ１和７份ｐｒｅＳ２的核苷酸序列，均发生了一个至多个位点的点突变。结论ＰＢＭＣ中存在的包膜基因不完整，因而不会形成完整的ＨＢＶ病毒颗粒，故不支持ＨＢＶ可潜伏于ＰＢＭＣ并发展成为体内ＨＢＶ再感染的来源。ｐｒｅＳ１点突变编码的氨基酸位点，集中在ａａ２１～４７区域，可能会影响ＨＢＶ的吸附和穿入，及组织亲嗜性的改变。ＨＢＶ亚基因片段在ＰＢＭＣ中，是否会影响细胞的功能，有待进一步研究。
Objective To study the significance of mutations of HBV preS and S genes in peripheral blood mononuclear cells (PBMC). Methods Srea and PBMCs of 19 chronic hepatitis B patients were collected. The S, preS1 and preS2 gene fragments of HBV were separately amplified by PCR, and 5 cases of preS1 and preS2 gene fragments in paired sera and PBMC were sequenced. Results The positive rates of S, preS1 and preS2 gene fragments in serum and PBMC were 100%, 94.7%, 100% and 0,26.3%, 26.3% respectively. Sequence analysis of preS1 and preS2 genes showed that in 8/10 specimens there were point mutations in preS1 and 7/10 mutations in preS2; while in the others (2 of preS1 and 3 of preS2) the sequences were identical to that of wildtype HBV. Conclusion No fulllength HBV genome in PBMC was detected by PCR, this is a fact not supporting that HBV can replicate, assemble and release from PBMC. The amino acid changes predicted mutatieds from nucleotide were focused in aa2147 region, which might affect adsorption and penetration of HBV, and alteration in tissue tropism. Whether the presence of HBV subgenomic fragments in PBMC can affect cell function should be pursued.
出处
《中华实验和临床病毒学杂志》
CAS
CSCD
1999年第2期148-152,共5页
Chinese Journal of Experimental and Clinical Virology
基金
国家自然科学基金
关键词
乙型肝炎病毒
前S/S基因
基因变异
PBMC
Peripheral blood mononuclear cell(PBMC)Hepatitis B virusPreS/S geneMutation
