The role of feline aminopeptidase N as a receptor for infectious bronchitis virus

Abstract

Feline aminopeptidase N (fAPN) has been shown to serve as a receptor for feline, canine, porcine and human coronaviruses. Our objective was to determine if fAPN can serve as a receptor for infectious bronchitis virus (IBV). Feline kidney cells that express fAPN and hamster kidney fibroblasts that do not express fAPN were inoculated with IBV and monitored for replication by indirect fluorescent assay and confocal microscopy and in chicken embryonated eggs. The results showed that the feline cells were permissive to IBV but the hamster cells were not. The hamster cells became permissive to IBV after transfection with a fAPN cDNA suggesting that the feline APN molecule plays a role in IBV entry.

Expression of the C-type lectins DC-SIGN or L-SIGN alters host cell susceptibility for the avian coronavirus, infectious bronchitis virus

“…Although the virus was first identified almost 80 years ago, the primary receptor for IBV has not been identified. There was speculation that feline aminopeptidase N (fAPN), which can serve as a common receptor for many Alphacoronaviruses, is a receptor for IBV (Miguel et al, 2002). This was based in part on the ability of the Ark99 strain of IBV to infect feline kidney cells (Miguel et al, 2002).…”

“…There was speculation that feline aminopeptidase N (fAPN), which can serve as a common receptor for many Alphacoronaviruses, is a receptor for IBV (Miguel et al, 2002). This was based in part on the ability of the Ark99 strain of IBV to infect feline kidney cells (Miguel et al, 2002). However, these studies were not confirmed with additional isolates of IBV and the current view is that APN is not a functional receptor utilized by IBV.…”

Infection of HeLa cells by avian infectious bronchitis virus is dependent on cell status

“…Transmissible gastroenteritis virus binding to sialic acid is required in enteropathogenesis, while binding to porcine aminopeptidase N is required for the infection of cultured cells (Krempl et al, 2000). Although the natural IBV receptor is not identified, it is reported that feline aminopeptidase N can be used as a common cellular receptor by group 1 coronaviruses of human, dogs and pigs and group 3 member IBV (Tresnan et al, 1996;Miguel et al, 2002). Our study demonstrated that monoclonal antibody WM15 to human aminopeptidase N could not prevent IBV infection in HeLa.…”

Binding characterization of determinants in porcine aminopeptidase N, the cellular receptor for transmissible gastroenteritis virus

“…Previously, fAPN has been identified as a receptor for an avian coronavirus, namely, infectious bronchitis virus (IBV). The assertion was based on the observation that the hamster kidney fibroblasts became permissive to IBV strain Ark 99 after transfection with a fAPN cDNA (Miguel et al, 2002). Interestingly, both transient transfection and stable expression of fAPN on the same cell line (BHK cells) rescued FIPV and TGEV infection in non-permissive BHK cells; however, fAPN expression did not rescue infection by the prototype IBV strain Mass41 (Chu et al, 2007).…”

“…It is a type II glycoprotein of about 150-160 kDa, in molecular weight and its large extracellular carboxy-terminal domain contains a pentapeptide catalytic sequence (His-Glu-X-X-His), characteristic of zinc metalloprotease (Hooper, 1994). APN is distributed on the surface of diverse cell lines, for example, it is expressed on the plasma membranes of granulocytes, lymphocytes, monocytes, fibroblasts and synaptic membrane in the central nervous system (Miguel et al, 2002). It is highly expressed on the surface of the brush border membrane of the enterocytes, where it participates in the final steps of digestion by cleaving peptides preferentially after N-terminal neutral amino acids.…”