Yoshikawa Tomoki, Iwasaki Takuya, Ida-Hosonuma Miki, Yoneyama Mitsutoshi, Fujita Takashi, Horie Hitoshi, Miyazawa Miwako, Abe Shinobu, Simizu Bunsiti, Koike Satoshi
Department of Microbiology and Immunology, Tokyo Metropolitan Institute for Neuroscience, Tokyo Metropolitan Organization for Medical Research, Musashidai, Fuchu-shi, Tokyo, 183-8526, Japan.
J Virol. 2006 May;80(9):4313-25. doi: 10.1128/JVI.80.9.4313-4325.2006.
Replication of poliovirus (PV) is restricted to a few sites, including the brain and spinal cord. However, this neurotropism is not conserved in cultured cells. Monkey kidney cells become susceptible to PV infection after cultivation in vitro, and cell lines of monolayer cultures from almost any tissue of primates are susceptible to PV infection. These observations suggest that cellular changes during cultivation are required for acquisition of susceptibility. The molecular basis for the cellular changes during this process is not known. We investigated the relationship between PV susceptibility and interferon (IFN) response in primary cultured kidney and liver cells derived from transgenic mice expressing human PV receptor and in several primate cell lines. Both kidneys and liver in vivo showed rapid IFN response within 6 h postinfection. However, monkey and mouse kidney cells in culture and primate cell lines, which were susceptible to PV, did not show such rapid response or showed no response at all. On the other hand, primary cultured liver cells, which were partially resistant to infection, showed rapid IFN induction. The loss of IFN inducibility in kidney cells was associated with a decrease in expression of IFN-stimulated genes involved in IFN response. Mouse kidney cells pretreated with a small dose of IFN, in turn, restored IFN inducibility and resistance to PV. These results strongly suggest that the cells in culture acquire PV susceptibility during the process of cultivation by losing rapid IFN response that has been normally maintained in extraneural tissues in vivo.
脊髓灰质炎病毒(PV)的复制局限于少数部位,包括脑和脊髓。然而,这种嗜神经性在培养细胞中并不保守。猴肾细胞在体外培养后对PV感染变得易感,并且来自灵长类几乎任何组织的单层培养细胞系都对PV感染易感。这些观察结果表明,培养过程中的细胞变化是获得易感性所必需的。这一过程中细胞变化的分子基础尚不清楚。我们研究了表达人PV受体的转基因小鼠原代培养的肾细胞和肝细胞以及几种灵长类细胞系中PV易感性与干扰素(IFN)反应之间的关系。体内的肾和肝在感染后6小时内均显示出快速的IFN反应。然而,培养中的猴和小鼠肾细胞以及对PV易感的灵长类细胞系并未显示出这种快速反应或根本没有反应。另一方面,对感染部分抗性的原代培养肝细胞显示出快速的IFN诱导。肾细胞中IFN诱导性的丧失与参与IFN反应的IFN刺激基因表达的降低有关。反过来,用小剂量IFN预处理的小鼠肾细胞恢复了IFN诱导性和对PV的抗性。这些结果强烈表明,培养中的细胞在培养过程中通过丧失在体内神经外组织中通常维持的快速IFN反应而获得PV易感性。