Study of the extensively usable coronaviruses infrction model-mouse production.

猫传染性腹膜炎病毒(FIPV)是猫科动物感染的第1组冠状病毒之一，根据其体外生长能力和与其他冠状病毒的抗原性关系可分为两类。包括II型FIPV在内的一些第1组冠状病毒使用猫氨酸氨基肽酶N(FAPN)作为细胞表面受体。另一方面，有一种观点认为，I型FIPV通过不同的受体进入靶细胞。为了分析I型和II型FIPV与fAPN的关系，我们利用大肠杆菌表达系统和以重组fAPN为抗原的抗fAPN单抗和多克隆抗体(MAb和Pab)制备了重组fAPN。这些抗体与猫全胎细胞(FCWF-4)发生反应。我们检测了这些抗体是否能抑制病毒对fcwf-4细胞的感染。结果，抗fAPN多克隆抗体阻断了这两种FIPV的感染，而单抗仅阻断了II型FIPV的感染。这些结果表明，fAPN是两种FIPV感染靶细胞的原因。

Feline infectious peritonitis virus (FIPV), one of group 1 coronavirus infective to cats, is divided into two types on the basis of in vitro growth ability and antigenic relationship to other coronaviruses. Some group 1 coronaviruses including type II FIPV use feline aminopeptidase N (fAPN) as a cell surface receptor. On the other hand, there is an opinion that type I FIPV enters to target cells via a different receptor. To analyze a relationship between type I and II FIPV and fAPN, we produced recombinant fAPN using Escherichia coli (E.coli ) expression system and anti-fAPN monoclonal and polyclonal antibodies (MAbs and PAb) by use of the recombinant fAPN as antigen. These antibodies were reacted to Felis catus whole fetus (fcwf-4) cells. We examined whether these antibodies inhibit viral infection to fcwf-4 cells or not. In the result, Anti-fAPN polyclonal antibody blocked infection with both types of FIPV, while monoclonal antibodies blocked only type II FIPV. These results suggest that fAPN responsible for both types FIPV infection to target cells.