de la Torre J C, Martínez-Salas E, Diez J, Villaverde A, Gebauer F, Rocha E, Dávila M, Domingo E
Centro de Biología Molecular (Consejo Superior de Investigaciones Científicas), Universidad Autónoma de Madrid, Spain.
J Virol. 1988 Jun;62(6):2050-8. doi: 10.1128/JVI.62.6.2050-2058.1988.
Virus and cells evolve during serial passage of cloned BHK-21 cells persistently infected with foot-and-mouth disease virus (FMDV). These carrier cells, termed C1-BHK-Rc1 (J.C. de la Torre, M. Dávila, F. Sobrino, J. Ortín, and E. Domingo, Virology 145:24-35, 1985), become constitutively resistant to the parental FMDV C-S8c1. Curing of late-passage C1-BHK-Rc1 cells of FMDV by ribavirin treatment (J.C. de la Torre, B. Alarcón, E. Martínez-Salas, L. Carrasco, and E. Domingo, J. Virol. 61:233-235, 1987) did not restore sensitivity to FMDV C-S8c1. The resistance of C1-BHK-Rc1 cells to FMDV C-S8c1 was not due to an impairment of attachment, penetration, or uncoating of the particles but to some intracellular block that resulted in a 100-fold decrease in the amount of FMDV RNA in the infected cells. FMDV R59, the virus isolated from late-passage carrier cells, partly overcame the cellular block and was more cytolytic than FMDV C-S8c1 for BHK-21 cells. Sequencing of the VP1 gene from nine viral clones from C1-BHK-Rc1 cells showed genetic heterogeneity of 5 X 10(-4) substitutions per nucleotide. Mutations were sequentially fixed during persistence. In addition to resistance to FMDV C-S8c1, C1-BHK-Rc1 cells showed a characteristic round cell morphology, and compared with BHK-21 cells, they grew faster in liquid culture, were less subject to contact inhibition of growth, and had an increased ability to form colonies in semisolid agar. Reconstitution of a persistent infection was readily attained with late-passage C1-BHK-Rc1 cells and FMDV C-S8c1 or FMDV R59. The results suggest that coevolution of BHK-21 cells and FMDV contributes to the maintenance of persistence in cell culture.
在口蹄疫病毒（FMDV）持续感染的克隆BHK - 21细胞的连续传代过程中，病毒和细胞发生了进化。这些载体细胞被称为C1 - BHK - Rc1（J.C. 德拉托雷、M. 达维拉、F. 索布里诺、J. 奥尔廷和E. 多明戈，《病毒学》145:24 - 35，1985），对亲代FMDV C - S8c1具有组成型抗性。用利巴韦林处理使晚期传代的C1 - BHK - Rc1细胞中的FMDV清除（J.C. 德拉托雷、B. 阿拉孔、E. 马丁内斯 - 萨拉斯、L. 卡拉斯科和E. 多明戈，《病毒学杂志》61:233 - 235，1987）后，并未恢复对FMDV C - S8c1的敏感性。C1 - BHK - Rc1细胞对FMDV C - S8c1的抗性不是由于病毒颗粒的附着、穿透或脱壳受损，而是由于某种细胞内阻滞，导致感染细胞中FMDV RNA的量减少了100倍。从晚期传代载体细胞中分离出的病毒FMDV R59部分克服了细胞阻滞，并且对BHK - 21细胞的细胞溶解性比FMDV C - S8c1更强。对来自C1 - BHK - Rc1细胞的九个病毒克隆的VP1基因进行测序，结果显示每个核苷酸的遗传异质性为5×10⁻⁴个替换。在持续感染过程中，突变依次固定。除了对FMDV C - S8c1具有抗性外，C1 - BHK - Rc1细胞还呈现出特征性的圆形细胞形态，并且与BHK - 21细胞相比，它们在液体培养中生长更快，对生长的接触抑制作用较小，并且在半固体琼脂中形成菌落的能力增强。用晚期传代的C1 - BHK - Rc1细胞与FMDV C - S8c1或FMDV R59很容易重建持续感染。结果表明，BHK - 21细胞与FMDV的共同进化有助于在细胞培养中维持持续感染。
