Characterization of monoclonal antibodies to the hemagglutinin-esterase glycoprotein of a bovine coronavirus associated with winter dysentery and cross-reactivity to field isolates

Abstract

Seven hybridoma cell lines producing monoclonal antibodies (MAbs) to the hemagglutinin-esterase (HE) glycoprotein of bovine coronavirus (BCV) were obtained from BALB/c mice that were immunized with an enriched peplomeric fraction of the winter dysentery (WD)-associated strain BCQ.2590. The specificities of these MAbs to either the dimeric (140-kDa) or the monomeric (65-kDa) form of the HE glycoprotein were determined by Western immunoblotting experiments with purified virus and immunoprecipitation tests with [ 35 S]methionine-labelled infected cell extracts. Four of these anti-HE MAbs inhibited the hemagglutinating activity of the virus and three weakly neutralized its infectivity in vitro. In addition, competition binding assays allowed for the definition of two independent antigenic domains (domains A and D) and two overlapping antigenic domains (domains B and C) for the HE glycoprotein of the WD-associated strain; epitopes located within antigenic domain A were not associated with hemagglutination inhibition (HAI) and virus neutralization activities. In HAI tests, the four anti-HA MAbs defined two distinct antigenic subgroups among 24 BCV field isolates that have been associated with either typical outbreaks of WD or neonatal calf diarrhea (NCD) in Quebec dairy herds from 1986 to 1996. The Quebec WD-associated strains of BCV, as well as some of the NCD-associated strains isolated since 1991, fell within a subgroup distinct from that of the prototype Mebus strain.

Broadly targeted multiprobe QPCR for detection of coronaviruses: Coronavirus is common among mallard ducks (Anas platyrhynchos)

“…Twenty-two human and animal strains, representative of the four CoV groups, including SARS-CoV, were analysed. The following references describe the origin of the collection of CoV strains (Adzhar et al, 1995;Bohl et al, 1972;Cavanagh and Davis, 1993;Darbyshire et al, 1979;Davelaar et al, 1984;Drosten et al, 2003;Evermann et al, 1981;Fields, 1973;Hamre and Procknow, 1966;Kahn and McIntosh, 2005;Kourtesis et al, 2001;Lavi et al, 1984;Milane et al, 1997;Pratelli et al, 2003a,b;Shaw et al, 1996).…”

Bovine coronaviruses associated with enteric and respiratory diseases in Canadian dairy cattle display different reactivities to anti-HE monoclonal antibodies and distinct amino acid changes in their HE, S and ns4.9 protein

“…The specificities of the MAbs toward 65 and/or 140 kDa polypeptides, corresponding to the monomeric and dimeric forms of the HE glycoproteins, have been determined by Western blotting and radioimmunoprecipitation experiments. No reactivity was observed toward the S (100 or 200 kDa) glycoprotein, and none of these anti-HE MAbs had neutralizing activity against the homologous and Mebus BCoV strains (Milane et al, 1997).…”

“…Despite their association to different clinical pathologies, BCoV isolates apparently belong to a single serotype on the basis of virus neutralisation (VN) and hemagglutination inhibition (HAI) tests using polyclonal hyperimmune sera. However, data obtained from recent serological findings using anti-HE and anti-S MAbs suggest the existence of different subgroups of BCoV, each containing EBCoV and WDBCoV strains responsible for either NCD, WD or chronic shedding in adult cattle (El Ghorr et al, 1989;Tsunemitsu and Saif, 1995;Milane et al, 1997;Fukutomi et al, 1999). Antigenic and genomic variations have been also recently reported among EBCoV and RBCoV strains (Chouljenko et al, 1998;Hasoksuz et al, 1999).…”

“…The RBCoV reference strain OK-0514, isolated from the nasal swab of a calf with clinical respiratory tract disease subsequent to shipping from Oklahoma to a feedlot in Kansas, was kindly provided to us by J. Storz, School of Veterinary Medicine of Louisiana (Storz et al, 1996). Field strains of EBCoV associated with either diarrhea in newborn calves or WD in adult cattle were obtained from affected dairy herds from different geographical areas in Quebec, Canada (Dea et al, 1995;Milane et al, 1997). The RBCoV strain BCQ.3994 was isolated from the lungs of pneumonic growing calves from a dairy farm in Southern Quebec that developed signs of respiratory tract disease during 1998, whereas two other Canadian RBCoV strains (BCO.43277 and BCO.44175) were isolated from pneumonic growing calves with pneumonia from two different Ontario dairy farms during 1997 (kindly provided to us by S. Carman, Ontario Ministry of Agriculture and Fisheries, Ontario Veterinary College, Guelph, Ontario, Canada).…”

“…For serological studies, monoclonal antibodies 1D6-2, 1D6-3 and 9F2-1R directed to the HE glycoprotein of the Quebec WDBCoV reference strain BCQ.2590 were used (Milane et al, 1997), as well as rabbit hyperimmune sera produced to the concentrated and purified Mebus and BCQ.2590 strains (Dea et al, 1995). The anti-HE MAbs were obtained following fusion experiments with splenocytes from Balb/c mice which have been immunized with an enriched peplomeric fraction of the WDBCoV BCQ.2590 strain (Milane et al, 1997). The specificities of the MAbs toward 65 and/or 140 kDa polypeptides, corresponding to the monomeric and dimeric forms of the HE glycoproteins, have been determined by Western blotting and radioimmunoprecipitation experiments.…”