Sansonno D, Lotesoriere C, Cornacchiulo V, Fanelli M, Gatti P, Iodice G, Racanelli V, Dammacco F
Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy.
Blood. 1998 Nov 1;92(9):3328-37.
Although hepatitis C virus (HCV) mainly affects hepatocytes, infection is widespread and involves immunologically privileged sites. Whether lymphoid cells represent further targets of early HCV infection, or whether other cells in the hematopoietic microenvironment may serve as a potential virus reservoir, is still unclear. We studied whether pluripotent hematopoietic CD34(+) cells support productive HCV infection and can be used to establish an in vitro infection system for HCV. Six patients were selected as part of a cohort of HCV chronic carriers who developed a neoplastic disease. Reverse transcriptase-polymerase chain reaction (RT-PCR) and branched DNA signal amplification assays were used to detect and quantitate HCV RNA in extracted nucleic acids from purified bone marrow and peripheral blood CD34(+) cells. Direct in situ RT-PCR, flow cytometry analysis, and immunocytochemistry were applied to demonstrate specific viral genomic sequences and structural and nonstructural virus-related proteins in intact cells. Results indicated that both positive and negative HCV RNA strands and viral proteins were present in CD34(+) cells from all HCV-positive patients and in none of the controls. Additional experiments showed that a complete viral cycle took place in CD34(+) cells in vitro. Spontaneous increases in viral titers indicated that virions were produced by infected hematopoietic progenitor cells. To further define the cellular tropism, we attempted to infect CD34(+) cells in vitro. We were unable to demonstrate viral uptake by cells. These findings suggest that HCV replication can occur in the early differentiation stages of hematopoietic progenitor cells, and that they may be an important source of virus production.
尽管丙型肝炎病毒（HCV）主要影响肝细胞，但感染广泛存在且涉及免疫赦免部位。淋巴细胞是否代表HCV早期感染的进一步靶细胞，或者造血微环境中的其他细胞是否可能作为潜在的病毒储存库，目前仍不清楚。我们研究了多能造血CD34(+)细胞是否支持HCV的有效感染，并能否用于建立HCV的体外感染系统。选择6例作为HCV慢性携带者队列中的一部分，这些携带者发生了肿瘤性疾病。采用逆转录聚合酶链反应（RT-PCR）和分支DNA信号扩增测定法，检测和定量从纯化的骨髓和外周血CD34(+)细胞中提取的核酸中的HCV RNA。应用直接原位RT-PCR、流式细胞术分析和免疫细胞化学，以证明完整细胞中特定的病毒基因组序列以及病毒结构和非结构相关蛋白。结果表明，所有HCV阳性患者的CD34(+)细胞中均存在HCV RNA正负链和病毒蛋白，而对照组均未检测到。进一步实验表明，体外CD34(+)细胞中发生了完整的病毒循环。病毒滴度的自发增加表明感染的造血祖细胞产生了病毒粒子。为进一步确定细胞嗜性，我们尝试在体外感染CD34(+)细胞。我们未能证明细胞摄取病毒。这些发现表明，HCV复制可发生在造血祖细胞的早期分化阶段，并且它们可能是病毒产生的重要来源。
