经血传播病毒在肝脏及肝外组织的感染状况

Detection of Transfusion transmitted virus in hepatic and extrahepatic tissues using in situ hybridization

探讨ＴＴＶ在肝脏及肝外组织中的定位、分布及其意义。方法通过ＰＣＲ方法扩增ＴＴＶ基因组 ＯＲＦ_２中 １２３ ｂｐ的 ＤＮＡ片段，构建 ＴＴＶ ＤＮＡ质粒并克隆，序列分析表明与日本 ＡＢＯ１１４９４序列具有高度同源性。采用地高辛标记ＴＴＶ ＤＮＡ探针并与组织进行原位杂交，检测了２２例因肝病死亡患者的肝脏、脾脏、肾脏、胃、小肠等组织内ＴＴＶ ＤＮＡ感染状况。结果 ８例肝脏检出ＴＴＶ ＤＮＡ， ５例肾脏、 ４例脾脏、 ２例小肠、２例胃检出ＴＴＶ ＤＮＡ。阳性信号在组织中分布呈局灶性或散在胞浆型。肝脏感染度较其它组织高。阳性细胞与组织炎症坏死无固定病理解剖学关系。结论支持ＴＴＶ有嗜肝性的观点；ＴＴＶ可以感染肝外多种组织并可能导致ＴＴＶ持续感染。

Objective To investigate the location, distribution and significance of transfusion transmitted virus (TTV) in the liver and extrahepatic tissues. Methods A 123 hp fragment of TTV DNA within ORF_2 was amplified by PCR reaction and cloned into PCR2.1 vector. DNA sequencing revealed that the inserted fragment was highly isogenous with Ja- pan ABO11494 strain. The inserted fragment was labeled with digoxigenin. Segment of liver, spleen, kidney, stomach and intestine tissues from 22 patients dead of liver diseases were detected by in situ hybridization with this digoxigenin labeled TTV DNA probe. Results TTV DNA was detected in & livers, 4 kidneys, 3 spleens, 2 intestines, and 2 stomachs. The positive cells of TTV DNA in livers were higher than that in other tissues. No obvious pathological topographical relationship of tissue inflammatory reaction with positive cells was found. Conclusion TTV can infect hepatic and ex-hepatic tissues and may cause persistent infection.