Wersto R P, Rosenthal E R, Seth P K, Eissa N T, Donahue R E
Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
J Virol. 1998 Dec;72(12):9491-502. doi: 10.1128/JVI.72.12.9491-9502.1998.
First-generation adenovirus (Ad) vectors that had been rendered replication defective by removal of the E1 region of the viral genome (DeltaE1) or lacking the Ad E3 region in addition to E1 sequences (DeltaE1DeltaE3) induced G2 cell cycle arrest and inhibited traverse across G1/S in primary and immortalized human bronchial epithelial cells. Cell cycle arrest was independent of the cDNA contained in the expression cassette and was associated with the inappropriate expression and increase in cyclin A, cyclin B1, cyclin D, and cyclin-dependent kinase p34(cdc2) protein levels. In some instances, infection with DeltaE1 or DeltaE1 DeltaE3 Ad vectors produced aneuploid DNA histogram patterns and induced polyploidization as a result of successive rounds of cell division without mitosis. Cell cycle arrest was absent in cells infected with a second-generation DeltaE1Ad vector in which all of the early region E4 except the sixth open reading frame was also deleted. Consequently, E4 viral gene products present in DeltaE1 or DeltaE1 DeltaE3 Ad vectors induce G2 growth arrest, which may pose new and unintended consequences for human gene transfer and gene therapy.
第一代腺病毒（Ad）载体通过去除病毒基因组的E1区域（ΔE1）而使其复制缺陷，或除E1序列外还缺少Ad E3区域（ΔE1ΔE3），可诱导原代和永生化人支气管上皮细胞发生G2期细胞周期停滞，并抑制其穿越G1/S期。细胞周期停滞与表达盒中所含的cDNA无关，且与细胞周期蛋白A、细胞周期蛋白B1、细胞周期蛋白D和细胞周期蛋白依赖性激酶p34（cdc2）蛋白水平的不适当表达和增加有关。在某些情况下，用ΔE1或ΔE1ΔE3 Ad载体感染会产生非整倍体DNA直方图模式，并由于连续多轮无有丝分裂的细胞分裂而诱导多倍体化。用第二代ΔE1Ad载体感染的细胞中不存在细胞周期停滞，在第二代载体中除第六个开放阅读框外所有早期区域E4也被删除。因此，存在于ΔE1或ΔE1ΔE3 Ad载体中的E4病毒基因产物可诱导G2期生长停滞，这可能给人类基因转移和基因治疗带来新的意外后果。
