Calain P, Monroe M C, Nichol S T
Division of Viral and Rickettsial Diseases, Centers for Disease Control and Prevention, Mailstop G14, 1600 Clifton Road, N.E., Atlanta, Georgia 30329-4018, USA.
Virology. 1999 Sep 15;262(1):114-28. doi: 10.1006/viro.1999.9915.
Ebola virus (Zaire subtype) is associated with high mortality disease outbreaks that commonly involve human to human transmission. Surviving patients can show evidence of prolonged virus persistence. The potential for Ebola virus to generate defective interfering (DI) particles and establish persistent infections in tissue culture was investigated. It was found that serial undiluted virus passages quickly resulted in production of an evolving population of virus minireplicons possessing both deletion and copyback type DI genome rearrangements. The tenth undiluted virus passage resulted in the establishment of virus persistently infected cell lines. Following one or two crises, these cells were stably maintained for several months with continuous shedding of infectious virus. An analysis of the estimated genome lengths of a selected set of the Ebola virus minireplicons and standard filoviruses revealed no obvious genome length rule, such as "the rule of six" found for the phylogenetically related Paramyxovirinae subfamily viruses. Minimal promoters for Ebola virus replication were found to be contained within 156 and 177 nucleotide regions of the genomic and antigenomic RNA 3' termini, respectively, based on the length of authentic termini retained in the naturally occurring minireplicons analyzed. In addition, using UV-irradiated preparations of virus released from persistently infected cells, it was demonstrated that Ebola virus DI particles could potentially be used as natural minireplicons to assay standard virus support functions.
埃博拉病毒（扎伊尔亚型）与高死亡率的疾病暴发有关，这种暴发通常涉及人际传播。幸存患者可显示出病毒长期持续存在的证据。对埃博拉病毒产生缺陷干扰（DI）颗粒并在组织培养中建立持续感染的可能性进行了研究。结果发现，连续传代未稀释的病毒很快导致产生一群不断进化的病毒微型复制子，这些复制子具有缺失型和回环型DI基因组重排。第10次传代未稀释的病毒导致建立了持续感染病毒的细胞系。经过一两次危机后，这些细胞稳定维持了几个月，持续释放有传染性的病毒。对一组选定的埃博拉病毒微型复制子和标准丝状病毒的估计基因组长度进行分析，未发现明显的基因组长度规律，如在系统发育相关的副粘病毒亚科病毒中发现的“六规则”。基于分析的天然存在的微型复制子中保留的真实末端长度，发现埃博拉病毒复制的最小启动子分别包含在基因组和反基因组RNA 3'末端的156和177个核苷酸区域内。此外，使用从持续感染细胞中释放的紫外线照射病毒制剂，证明埃博拉病毒DI颗粒有可能用作天然微型复制子来检测标准病毒的支持功能。
