Serological studies of transmissible gastroenteritis in Great Britain, using a competitive ELISA

Brown, IH; Paton, David

doi:10.1136/vr.128.21.500

Cited by 14 publications

(19 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar results were obtained by Brown and Paton (2). The results of the competitive inhibition ELISA, therefore, most probably underestimate the real number of TGEV-infected sows.…”

Section: Original Paperssupporting

confidence: 85%

See 1 more Smart Citation

A sero‐epizootiological study of porcine respiratory coronavirus in belgian swine

Pensaert

Cox

Deun

et al. 1993

Veterinary Quarterly

View full text Add to dashboard Cite

SUMMARYA porcine respiratory coronavirus (PRCV), antigenically closely related to transmissible gastroenteritis virus (TGEV), appeared in the European swine population in 1984. The present serological study was performed to obtain insight into the epizootiology of PRCV and of TGEV PRCV-induced neutralizing antibodies were found in 90.6 per cent of the 160 sera collected from sows at slaughter, demonstrating the enzootic appearance of PRCV in the Belgian swine population. A serological study of fattening swine on 33 farms revealed that 11 farms situated in an area with a high farm density (all farms within 4 km2) and I I on 22 closed breedingfattening farms situated in areas with a low farm density (only one to four farms per 12 km2) were infected with PRCV throughout the year, whereas the other 11 closed breedingfattening farms were temporarily free of PRCV PRCV disappeared from the farms mainly in spring and summer. All the 11 farms became reinfected in autumn or winter, indicating that PRCV is regularly reintroduced in farms in the colder seasons.There was no correlation between the herd size and the temporary disappearance of PRCV from farms. It was observed on some farms that PRCV could infect pigs shortly after weaning in the presence of declining maternal antibodies, indicating that PRCV can persist on a farm by regularly infecting newly weaned pigs.TGEV-specific antibodies were found in 7.6 per cent of the 160 sera from the slaughterhouse sows. TGEV-specific antibodies were also detected in sera from fattening swine of 5 of the above mentioned 33 farms. TGEV-outbreaks were not observed on these farms. During the last years, TGEV-outbreaks have rarely been diagnosed in Belgium. The present results suggest that TGEV infections still regularly occur but that they are not clinically manifest.

show abstract

“…Similar results were obtained by Brown and Paton (2). The results of the competitive inhibition ELISA, therefore, most probably underestimate the real number of TGEV-infected sows.…”

Section: Original Paperssupporting

confidence: 85%

“…On five farms, seronegative swine were present together with one or two swine with SN-titres equal to or higher than 24. Brown and Paton have made a similar observation (2). These high antibody titres in 5-month-old fatteners must have been induced by a PRCV infection.…”

Section: Original Papersmentioning

confidence: 57%

A sero‐epizootiological study of porcine respiratory coronavirus in belgian swine

Pensaert

Cox

Deun

et al. 1993

Veterinary Quarterly

View full text Add to dashboard Cite

show abstract

“…2,3,5,10,16,24,29 Although several tests have been developed to differentiate TGEV from PRCV seroconversion, to date only a few serologic surveys have been conducted nationally. 2,5 The existence of at least four antigenic sites (A, B, C, D) located at the N-terminus of the mature S protein has been described for TGEV. 4,7 The S protein epitopes can be subdivided into 2 categories based on their ability to induce VN antibodies.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of the Baculovirus-Expressed S Glycoprotein of Transmissible Gastroenteritis Virus (TGEV) as Antigen in a Competition ELISA to Differentiate Porcine Respiratory Coronavirus from TGEV Antibodies in Pigs

Sestak¹,

Zhou²,

Shoup³

et al. 1999

J VET Diagn Invest

View full text Add to dashboard Cite

Abstract. The spike (S) glycoprotein of the Miller strain of transmissible gastroenteritis virus (TGEV) was recently cloned and expressed in baculovirus. The recombinant S protein was used as the coating antigen in a competition (blocking) enzyme-linked immunosorbent assay (ELISA) in combination with monoclonal antibodies to the S protein epitope A (conserved on TGEV and porcine respiratory coronavirus [PRCV]) or epitope D (present on TGEV only) to differentiate PRCV-from TGEV-induced antibodies. One set (set A) of 125 serum samples were collected at different times after inoculation of caesarean-derived, colostrum-deprived (n ϭ 52) and conventional young pigs (n ϭ 73) with 1 of the 2 porcine coronaviruses or uninoculated negative controls (TGEV/PRCV/negative ϭ 75/30/20). A second set (set B) of 63 serum samples originated from adult sows inoculated with PRCV and the recombinant TGEV S protein or with mock-protein control and then exposed to virulent TGEV after challenge of their litters. Sera from set A were used to assess the accuracy indicators (sensitivity, specificity, accuracy) of the fixed-cell blocking ELISA, which uses swine testicular cells infected with the M6 strain of TGEV as the antigen source (ELISA 1) and the newly developed ELISA based on the recombinant S protein as antigen (ELISA 2). The sera from set B (adults) were tested for comparison. The plaque reduction virus neutralization test was used as a confirmatory test for the presence of antibodies to TGEV/PRCV in the test sera. The accuracy indicators for both ELISAs suggest that differential diagnosis can be of practical use at least 3 weeks after inoculation by testing the dual (acute/convalescent) samples from each individual in conjunction with another confirmatory (virus neutralization) antibody assay to provide valid and complete differentiation information. Moreover, whereas ELISA 1 had 10-20% false positive results to epitope D for PRCV-infected pigs (set A samples), no false-positive results to epitope D occurred using ELISA 2, indicating its greater specificity. The progression of seroresponses to the TGEV S protein epitopes A or D, as measured by the 2 ELISAs, was similar for both sets (A and B) of samples. Differentiation between TGEV and PRCV antibodies (based on seroresponses to epitope D) was consistently measured after the third week of inoculation.Transmissible gastroenteritis virus (TGEV), a prominent cause of neonatal diarrhea, causes death in 90-100% of seronegative pigs under 2 weeks of age and costs the US swine industry nearly $200 million/ year. 15,19 Surveys of TGEV antibodies in swine sera collected prior to the detection of porcine respiratory coronavirus (PRCV) indicated that 19-54% of swine herds in North America have antibodies, 17 but few differential serosurveys have been done since the detection of PRCV. 32 A variant of TGEV, referred to as PRCV, was isolated from pigs in Europe in 1986 and identified in the USA in 1989. 15,18,19 As reported from Iowa swine herds, a recent increase observed in TGEV/PRCV seropre...

show abstract

“…There are several available tests using MAbs based on the S protein epitopic differences that have been developed to differentiate TGEV and PRCV Abs [4,6,17,37,38].…”

Section: Competitive Elisamentioning

confidence: 99%

Molecular study of porcine transmissible gastroenteritis virus after serial animal passages revealed point mutations in S protein

et al. 2010

View full text Add to dashboard Cite

Porcine respiratory coronavirus is related genetically to porcine transmissible gastroenteritis virus with a large deletion in S protein. The respiratory virus is a mutated form that may be a consequence of the gastroenteritis virus's evolution. Intensive passages of the virus in its natural host may enhance the appearance of mutations and therefore may contribute to any attenuated form of the virus. The objective of this study was to characterize the porcine transmissible gastroenteritis virus TMK22 strain after passages in piglets from 1992 until 2007. A typical experimental infection, molecular characterization, and serological analysis were also carried out to further characterize and to evaluate any significant difference between strains. The sequence analysis showed two amino acid deletions and loss of an N-glycosylation site in transmissible gastroenteritis virus S protein after passages in piglets. Although these deletions were positioned at the beginning of the antigenic site B of S protein, no clinical differences were observed in piglets infected experimentally either with the native virus or the mutated one. Serological tests did not show any antibody reactivity difference between the two strains. In this article, we report that the S protein deletion did not affect the virus's pathogenicity. The variety of the virus's evolutionary forms may be a result, not only of the multiple passages in natural hosts, but also of other factors, such as different pathogens co-infection, nutrition, immunity, and others. Further studies need to be carried out to characterize the mutated strain.

show abstract

Serological studies of transmissible gastroenteritis in Great Britain, using a competitive ELISA

Cited by 14 publications

References 0 publications

A sero‐epizootiological study of porcine respiratory coronavirus in belgian swine

A sero‐epizootiological study of porcine respiratory coronavirus in belgian swine

Evaluation of the Baculovirus-Expressed S Glycoprotein of Transmissible Gastroenteritis Virus (TGEV) as Antigen in a Competition ELISA to Differentiate Porcine Respiratory Coronavirus from TGEV Antibodies in Pigs

Molecular study of porcine transmissible gastroenteritis virus after serial animal passages revealed point mutations in S protein

Contact Info

Product

Resources

About