Kopliku Lela, Relmy Anthony, Romey Aurore, Gorna Kamila, Zientara Stephan, Bakkali-Kassimi Labib, Blaise-Boisseau Sandra
Université Paris-Est, ANSES, Laboratoire de Santé Animale, UMR Virologie 1161, 14 rue Pierre et Marie Curie, 94700, Maisons-Alfort, France.
Arch Virol. 2015 Oct;160(10):2503-16. doi: 10.1007/s00705-015-2526-8. Epub 2015 Jul 28.
In addition to acute infection and disease, foot-and-mouth disease virus (FMDV) can cause persistent infection in ruminants. Such "carrier" animals represent a potential risk for FMDV transmission to susceptible animals. However, the mechanisms and the factors that determine FMDV persistence remain unknown. We describe here the establishment of FMDV type O persistent infection in a bovine epithelial cell line (Madin-Darby bovine kidney; MDBK). Preliminary experiments to assess the permissivity of MDBK cells to FMDV O infection revealed an unusual pattern of infection: after the initial phase of acute cell lysis, new monolayers formed within 48-72 h post-infection. We found that some cells survived cytolytic infection and subsequently regrew, thereby demonstrating that this bovine cell line can be persistently infected with FMDV type O. Further evidence that MDBK cells were persistently infected with FMDV includes: (i) detection of viral RNA in cells as well as in cell culture supernatants, (ii) detection of viral antigens in the cells by immunofluorescence analysis, and (iii) production of infectious viral particles for up to 36 cell passages. Furthermore, preliminary sequence analysis of persistent virus revealed a single nucleotide substitution within the VP1 coding region, resulting in the V50A amino acid substitution. This bovine model of FMDV persistence holds promise for the investigation of the viral and cellular molecular determinants that promote FMDV persistence.
除了引起急性感染和疾病外，口蹄疫病毒（FMDV）还可在反刍动物中引起持续性感染。这类“携带病毒”的动物是FMDV传播给易感动物的潜在风险。然而，决定FMDV持续性感染的机制和因素仍不清楚。我们在此描述了在牛上皮细胞系（Madin-Darby牛肾细胞；MDBK）中建立O型FMDV持续性感染的过程。评估MDBK细胞对O型FMDV感染易感性的初步实验揭示了一种不同寻常的感染模式：在急性细胞裂解的初始阶段之后，感染后48 - 72小时内形成了新的单层细胞。我们发现一些细胞在溶细胞性感染中存活下来并随后重新生长，从而证明这种牛细胞系可被O型FMDV持续性感染。MDBK细胞被FMDV持续性感染的进一步证据包括：（i）在细胞以及细胞培养上清液中检测到病毒RNA，（ii）通过免疫荧光分析在细胞中检测到病毒抗原，以及（iii）在多达36代细胞传代中产生有感染性的病毒颗粒。此外，对持续性病毒的初步序列分析显示VP1编码区内有一个单核苷酸替换，导致V50A氨基酸替换。这种FMDV持续性感染的牛模型有望用于研究促进FMDV持续性感染的病毒和细胞分子决定因素。
