Hatzoglou M, Hodgson C P, Mularo F, Hanson R W
Pew Center for Molecular Nutrition, Case Western Reserve University School of Medicine, Cleveland, OH 44106.
Hum Gene Ther. 1990 Winter;1(4):385-97. doi: 10.1089/hum.1990.1.4-385.
FTO-2B rat hepatoma cells acquired mouse VL30 retrotransposon(s) when infected with Moloney murine leukemia virus (MoMLV) recombinant retroviruses produced from psi 2 cells. The VL30 provirus was integrated into the rat genome, expressed at high levels, and its transcription induced 40-fold by dexamethasone, VL30 RNA was detected in hepatoma cells even without selection for the expression of the amino-3'-glycosyl phosphotransferase (neo) gene, which was co-transferred with a MoMLV retrovirus. However, the extent of transfer of the VL30 RNA was inversely related to the titer of the MoMLV recombinant retrovirus. The restriction map analysis of the transferred VL30 provirus was identical to the mouse VL30s of the NVL subfamily which is known to be a significant fraction of the transcriptionally active VL30 subset. Additionally, the regenerating liver from an adult rat, which was infected with a defective MoMLV-derived retrovirus, expressed VL30 RNA. These results indicate that great care should be given to the transfer of unwanted passengers, like VL30, present in retroviral packaging cell lines like the psi 2 cells, which are currently being used for gene therapy.
当用从psi 2细胞产生的莫洛尼鼠白血病病毒（MoMLV）重组逆转录病毒感染时，FTO - 2B大鼠肝癌细胞获得了小鼠VL30逆转座子。VL30前病毒整合到大鼠基因组中，高水平表达，其转录受地塞米松诱导提高40倍。即使在没有选择与MoMLV逆转录病毒共转移的氨基-3'-糖基磷酸转移酶（neo）基因表达的情况下，在肝癌细胞中也检测到了VL30 RNA。然而，VL30 RNA的转移程度与MoMLV重组逆转录病毒的滴度呈负相关。转移的VL30前病毒的限制性图谱分析与NVL亚家族的小鼠VL30相同，已知该亚家族是转录活性VL30子集的重要组成部分。此外，用缺陷型MoMLV衍生的逆转录病毒感染的成年大鼠再生肝表达VL30 RNA。这些结果表明，对于目前用于基因治疗的逆转录病毒包装细胞系（如psi 2细胞）中存在的不需要的“乘客”（如VL30）的转移，应格外小心。
