Delmas B, Gelfi J, Sjöström H, Noren O, Laude H
Unité de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Jouy-en-Josas, France.
Adv Exp Med Biol. 1993;342:293-8. doi: 10.1007/978-1-4615-2996-5_45.
We recently reported that porcine aminopeptidase-N (pAPN) acts as a receptor for transmissible gastroenteritis virus (TGEV). In the present work, we addressed the question of whether TGEV tropism is determined only by the virus-receptor interaction. To this end, different non-permissive cell lines were transfected with the porcine APN cDNA and tested for their susceptibility to TGEV infection. The four transfected cell lines shown to express pAPN at their membrane became sensitive to infection. Two of these cell lines were found to be defective for the production of viral particles. This suggests that other factor(s) than pAPN expression may be involved in the production of infectious virions. The pAPN-transfected cells were also tested for their susceptibility to several viruses which have a close antigenic relationship to TGEV. So far, we failed to evidence permissivity to the feline infectious peritonitis coronavirus FIPV and canine coronavirus CCV. In contrast, we found clear evidence that porcine respiratory coronavirus PRCV, a variant of TGEV which replicates efficiently in the respiratory tract but to a very low extent in the gut, may also utilise APN to gain entry into the host cells. This suggests that the switch between TGEV and PRCV tropisms in vivo may involve other determinant(s) than receptor recognition.
我们最近报道猪氨肽酶N（pAPN）作为传染性胃肠炎病毒（TGEV）的受体。在目前的工作中，我们探讨了TGEV嗜性是否仅由病毒-受体相互作用决定这一问题。为此，用猪APN cDNA转染不同的非允许细胞系，并检测它们对TGEV感染的敏感性。显示在其膜上表达pAPN的四个转染细胞系对感染变得敏感。发现其中两个细胞系在病毒颗粒产生方面存在缺陷。这表明除了pAPN表达外，其他因素可能也参与了感染性病毒粒子的产生。还检测了pAPN转染细胞对几种与TGEV有密切抗原关系的病毒的敏感性。到目前为止，我们未能证明它们对猫传染性腹膜炎冠状病毒FIPV和犬冠状病毒CCV具有易感性。相反，我们发现明确的证据表明，猪呼吸道冠状病毒PRCV，一种TGEV的变体，它在呼吸道中高效复制但在肠道中复制程度极低，也可能利用APN进入宿主细胞。这表明在体内TGEV和PRCV嗜性之间的转换可能涉及除受体识别之外的其他决定因素。
