Plaque Assay, Polypeptide Composition and Immunochemistry of Feline Infectious Peritonitis Virus and Feline Enteric Coronavirus Isolates

Abstract

I NTROD UCTI 0 N The coronaviral nature of feline infectious peritonitis virus (FIPV) and feline enteric coronavirus (FECV) has been well documented by morphological. physicochemical and antigenic studies 1 -10 • However. biochemical and detailed immunochemical analyses of FIPV and FECV have been difficult due to the inability to prepare sufficient quantities of viral material. Recently. we have been able to propagate FIPV and FECV in continuous cell culture of feline origin8.11-13.The purpose of this report is to describe the purification of fel ine coronavi ruses from infected cell culture and to compare five strains with respect to: 1) plaque characteristics. 2) viral structural polypeptide composition and 3) serologic reactivity of experimentally infected cats against the structural polypeptides of homologous and heterologous strains. MATERIALS AND METHODS Cells and vi rusFetal cat \'kIole fetus (fcwf-4) cells were used to propagate all feline coronavirus strains. Cells \\ere cultured with Eagle's 133 P. J. M. Rottier et al. (eds.), Molecular Biology and Pathogenesis of Coronaviruses

cDNA Cloning and Sequence Analysis of the Gene Encoding the Peplomer Protein of Feline Infectious Peritonitis Virus

“…Under the assumption that all potential glycosylation sites carry a carbohydrate group of 2K (Neuberger et al, 1972) and that a signal sequence is cleaved off, we predict a fully processed FIPV E2 protein of 216K. This agrees with the Mr of 210K found in SDS-PAGE for the mature protein (Boyle et al, 1984;de Groot et al, 1987a).…”

“…The FIPV virion consists of three main structural proteins: a 45K nucleocapsid protein, a 25K to 32K transmembrane glycoprotein (El) and a 210K peplomer glycoprotein (E2) (Horzinek et al, 1982;Boyle et al, 1984;de Groot et al, 1987a). The peplomer protein mediates the binding of virions to the host cell receptor and is involved in membrane fusion (Sturman & Holmes, 1983).…”

Intracellular RNAs of the Feline Infectious Peritonitis Coronavirus Strain 79-1146

“…As has been found for other coronaviruses, the FIPV virion consists of three main structural proteins: a 210K peplomer protein (E2); a 45K nucleocapsid protein (N) and an envelope protein (El), which appears in three forms of 32K, 30K and 25K (Boyle et al, 1984).…”

“…Cells and virus, Fells catus whole foetus (fcwf) D cells (Boyle et al, 1984) and the FIPV strain 79-114679- (McKeiman et al, 1981 were obtained from Dr N. C, Pedersen (School of Veterinary Medicine, University of California, Davis, Ca., U,S,A,), Fcwf-D cells were grown in Dulbecco's modified Eagle's medium, supplemented with 10~ foetal calf serum (DMEM-10~ FCS) and containing penicillin (100 IU/ml) and streptomycin (100 ~tg/ml).…”

Antigenic and Plaque Variations of Serotype II Feline Infectious Peritonitis Coronaviruses.

“…Serotype I FCoV isolates have been numerically superior [22] and predominantly distributed among cats [9]. These differences in antigenic properties are generally consistent with viral growth ability in vitro [2,22]; serotype II FCoVs propagate more readily than serotype I FCoVs in feline cell cultures such as Felis catus whole fetus-4 (fcwf-4) [13] and Crandell feline kidney (CRFK) cells. In addition, serotype II FCoVs are more efficiently neutralized by antiserum against canine coronavirus (CCV), indicating their closer antigenic relatedness with CCV.…”