Characterization of monoclonal antibodies to bovine enteric coronavirus and antigenic variability among Quebec isolates

Abstract

Twenty monoclonal antibodies (MAbs) were prepared against the Mebus strain of bovine enteric coronavirus, 14 of them reacting with the peplomeric S (gp 100) glycoprotein. Competition binding assays allowed the definition of at least 4 distinct antigenic domains for the S glycoprotein, designated as A, B, C, and D; epitopes associated to neutralizing activity being located in sites A, B, and C. One MAb directed to the hemagglutinin HE (gp 140/gp 65) glycoprotein inhibited the hemagglutinating activity of the virus, but had no neutralizing activity. Comparison of Quebec enteropathogenic BCV isolates using polyclonal antiserum and MAbs directed to the S glycoprotein confirmed their close antigenic relationship, but also revealed the occurrence of at least three distinct antigenic subgroups. Antigenic domain D was highly conserved among BCV isolates, as well as non-neutralizing epitopes assigned to antigenic domains A and C. The Minnesota strain of turkey enteric coronavirus could be distinguished from BCV isolates by MAbs directed to epitopes of antigenic domain C, whereas human coronavirus HCV-OC 43 could be distinguished by MAbs directed to epitopes of antigenic domain A. The porcine hemagglutinating encephalomyelitis virus could be distinguished from the other hemagglutinating coronaviruses by neutralizing epitopes located on antigenic domains A, B, and C.

Detection of a coronavirus from turkey poults in Europe genetically related to infectious bronchitis virus of chickens

“…Group 1 comprised viruses related antigenically to transmissible gastroenteritis virus while Group 2 contained, among others, bovine coronavirus (BCoV). Further antigenic (Michaud & Dea, 1993) and gene sequence analyses showed that some US and Canadian turkey coronavirus isolates were closely related to BCoV. The M and N genes of the turkey viruses had > 99% identity with the corresponding genes of BCoV (Dea et al, 1990;.…”

Isolation of bovine coronavirus (BCoV) in monolayers of HmLu-1 cells

“…Although viral replication was of low intensity, and discrepant results of seroneutralization in bottles and microplates were observed, differences in serological behavior of BCoV have already been reported: reactivity in relation to a panel of monoclonal antibodies (13), different values in relation to crossed seroneutralization between homologous and heterologous samples (21) and results of HI, as well as the susceptibility or resistance to higromicine B in samples isolated from eight North American states (10).…”

Characterization of bovine coronavirus isolates/from eight different states in the USA

“…Coronavirus has a high frequency of recombination, RNA polymerase lacks proofreading, and defective interfering RNAs are frequently generated in coronaviruses (Lai, 1995). BCV isolates from Canada have been divided into three subgroups on the basis of reactivity with monoclonal antibodies (mAbs) against spike protein of BCV (Michaud and Dea, 1993). Veterinary Microbiology 67 (1999) 221±230 The current modified, live BCV vaccine is not clinically effective (Thurber et al, 1977) and lack of clinical efficacy of the vaccine may be due to antigenic differences among the vaccine and field isolates of BCV.…”

“…A number of studies have been published in which American (Hussain et al, 1991), French (Vautherot and Laporte, 1983), Canadian (Michaud and Dea, 1993), English (El-Ghorr et al, 1989), and Scottish (Clark et al, 1990) isolates of BCV have been antigenically compared using a panel of mAbs. All of the previous studies, except the Canadian study, have failed to classify the BCV isolates into subgroups.…”

“…All of the previous studies, except the Canadian study, have failed to classify the BCV isolates into subgroups. A monoclonal (Michaud and Dea, 1993) on the basis of reactivity with a panel of mAbs.…”