Antigenic Cross-Reactivity between the Nucleocapsid Protein of Severe Acute Respiratory Syndrome (SARS) Coronavirus and Polyclonal Antisera of Antigenic Group I Animal Coronaviruses: Implication for SARS Diagnosis

Sun, Zhenzhao; Meng, Xiang‐Jin

doi:10.1128/jcm.42.5.2351-2352.2004

Cited by 70 publications

(75 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In this respect, a further study of those samples with the new Western blot analysis may provide useful information and thus warrant further investigation. Interestingly, our findings here also echoed a very recent report of the cross-reactivity of the N protein of SARS-CoV to antigenic group I animal CoVs (17). It is perhaps also noteworthy that the cross-reactivity could in theory be eliminated by reducing the amount of the N protein used for the production of the immunoblot, since there was a consistent difference in the protein band intensities between the SARS samples and the controls (Fig.…”

Section: Discussionsupporting

confidence: 76%

“…As a result, a test with the new Western immunoblot will be considered positive only if the lysate N protein and at least one of the other criterion proteins were detected simultaneously. This prerequisite of multiple markers in combinations limited the possible impact of the cross-reactivity of the N proteins observed here and elsewhere (17) without compromising the sensitivity of the immunoblot and thus provided an advantage over some currently available tests that relied on only a single N protein.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Use of Viral Lysate Antigen Combined with Recombinant Protein in Western Immunoblot Assay as Confirmatory Test for Serodiagnosis of Severe Acute Respiratory Syndrome

Guan

Chen

Tan

et al. 2004

Clin Vaccine Immunol

View full text Add to dashboard Cite

A Western immunoblot assay for confirmatory serodiagnosis of severe acute respiratory syndrome (SARS) was developed utilizing viral lysate antigens combined with a recombinant nucleocapsid protein, GST-N (glutathione S-transferase-nucleocapsid) of the SARS coronavirus (SARS-CoV). The viral lysate antigens were separated by electrophoresis and transblotted onto nitrocellulose membranes. The resultant membrane was subsequently added with the GST-N recombinant protein at a specific location. The positions of bands corresponding to some of the structural proteins immobilized on the membrane were then located and verified with mouse or rabbit antisera specific to the respective proteins. The Western immunoblot assay was able to detect antibodies to SARS-CoV in all 40 serum specimens from SARS patients and differentiate the SARSpositive samples from those of the healthy donor or non-SARS patient controls (150 samples) when set criteria were followed. In addition, when the immunoblot was used to test samples considered falsely positive by an in-house-developed SARS-specific enzyme-linked immunosorbent assay, band patterns different from those with samples from SARS patients were obtained.

show abstract

Section: Discussionsupporting

confidence: 76%

Section: Discussionmentioning

confidence: 99%

Use of Viral Lysate Antigen Combined with Recombinant Protein in Western Immunoblot Assay as Confirmatory Test for Serodiagnosis of Severe Acute Respiratory Syndrome

Guan

Chen

Tan

et al. 2004

Clin Vaccine Immunol

View full text Add to dashboard Cite

show abstract

“…Since the N proteins of the known coronaviruses are relatively conserved, the expressed N protein of the SARS-CoV in Escherichia coli cross-reacts with polyclonal antisera of some known animal coronaviruses in antigenic group I, including transmissible gastroenteritis virus, feline infectious peritonitis virus, and canine coronavirus (9), which raised concerns of potential false positives when the recombinant N protein of the SARS-CoV, whole-virus antigen extracts, or virus-infected cells are used as reagents. However, this concern is very minimal, since the two known human coronaviruses (strains 229E and OC43) do not cause severe clinical diseases and we still do not have data about the prevalence of the antibodies to other coronaviruses or relevant microorganisms in human populations (4,6,8).…”

mentioning

confidence: 99%

Use of the COOH Portion of the Nucleocapsid Protein in an Antigen-Capturing Enzyme-Linked Immunosorbent Assay for Specific and Sensitive Detection of Severe Acute Respiratory Syndrome Coronavirus

Qiu

Wang

et al. 2005

Clin Vaccine Immunol

View full text Add to dashboard Cite

Antibody detection with a recombinant COOH portion of the severe acute respiratory syndrome (SARS) coronavirus nucleocapsid (N) protein, N13 (amino acids 221 to 422), was demonstrated to be more specific and sensitive than that with the full-length N protein, and an N13-based antigen-capturing enzyme-linked immunosorbent assay providing a convenient and specific test for serodiagnosis and epidemiological study of SARS was developed.Severe acute respiratory syndrome (SARS) is a serious threat to public health and the economy on a global scale. A novel coronavirus, the SARS coronavirus (SARS-CoV), has been identified as the etiological agent for SARS (6). For serodiagnosis of the SARS-CoV infection in clinical microbiology laboratories, the recombinant antigen-based enzymelinked immunosorbent assay (ELISA) for detecting specific antibodies is well known to offer higher reproducibility and to be more easily standardized and less laborious than either an indirect immunofluorescence assay based on virus-infected cells or an ELISA based on whole-virus lysate and does not require cultivation of the SARS-CoV (12). Since the specific antibodies to nucleocapsid (N) protein are most abundant in the sera from SARS patients (5), several groups have developed some recombinant N protein-based ELISAs. In general, these new assays are more specific and sensitive than the ELISA based on whole-virus lysate, but some false-positive results still occurred with sera from non-SARS patients or healthy people, even with sera collected several years before the SARS outbreak (3,7,8,(10)(11)(12).Since the N proteins of the known coronaviruses are relatively conserved, the expressed N protein of the SARS-CoV in Escherichia coli cross-reacts with polyclonal antisera of some known animal coronaviruses in antigenic group I, including transmissible gastroenteritis virus, feline infectious peritonitis virus, and canine coronavirus (9), which raised concerns of potential false positives when the recombinant N protein of the SARS-CoV, whole-virus antigen extracts, or virus-infected cells are used as reagents. However, this concern is very minimal, since the two known human coronaviruses (strains 229E and OC43) do not cause severe clinical diseases and we still do not have data about the prevalence of the antibodies to other coronaviruses or relevant microorganisms in human populations (4,6,8). Therefore, it is important to identify the immunoreactive epitope of the N protein or other proteins specific to the SARS-CoV for serodiagnosis of SARS.In our previous study, the antigenicity of different regions of the SARS-CoV N protein was analyzed by using a protein microarray. Four important regions with possible epitopes were identified, and the full-length N protein and two truncated N proteins, N8 (comprising amino acids [aa] 51 to 422) and N13 (aa 221 to 422), reacted with all 52 sera from SARS patients (1). Among these recombinant proteins, N13 is the shortest one, which decreases the possibility of cross-reaction with antibodies to other microorga...

show abstract

“…Although the SARS-N protein shares low homology (approximately 20-30%) with N proteins of other HCoVs, a previous report has described that the SARS-N protein has strong crossreactivity with sera against HCoVs (Sun and Meng, 2004). Hence, anti-sera against SARS-CoV may be cross-reactive with other HCoVs.…”

Section: Discussionmentioning

confidence: 97%

Preparation and characterization of a novel monoclonal antibody specific to severe acute respiratory syndrome-coronavirus nucleocapsid protein

et al. 2006

View full text Add to dashboard Cite

Severe acute respiratory syndrome-coronavirus nucleocapsid (SARS-CoV N) protein has been found to be important to the processes related to viral pathogenesis, such as virus replication, interference of the cell process and modulation of host immune response; detection of the antigen has been used for the early diagnosis of infection. We have used recombinant N protein expressed in insect cells to generate 17 mAbs directed against this protein. We selected five mAbs that could be used in various diagnostic assays, and all of these mAbs recognized linear epitopes. Three IgG(2b) mAbs were recognized within the N-terminus of N protein, whereas the epitope of two IgG(1) mAbs localized within the C-terminus. These mAbs were found to have significant reactivity with both non-phosphorylated and phosphorylated N proteins, which resulted in high reactivity with native N protein in virus-infected cells; however, they did not show cross-reactivity with human coronavirus. Therefore, these results suggested that these mAbs would be useful in the development of various diagnostic kits and in future studies of SARS-CoV pathology.

show abstract

Antigenic Cross-Reactivity between the Nucleocapsid Protein of Severe Acute Respiratory Syndrome (SARS) Coronavirus and Polyclonal Antisera of Antigenic Group I Animal Coronaviruses: Implication for SARS Diagnosis

Cited by 70 publications

References 9 publications

Use of Viral Lysate Antigen Combined with Recombinant Protein in Western Immunoblot Assay as Confirmatory Test for Serodiagnosis of Severe Acute Respiratory Syndrome

Use of Viral Lysate Antigen Combined with Recombinant Protein in Western Immunoblot Assay as Confirmatory Test for Serodiagnosis of Severe Acute Respiratory Syndrome

Use of the COOH Portion of the Nucleocapsid Protein in an Antigen-Capturing Enzyme-Linked Immunosorbent Assay for Specific and Sensitive Detection of Severe Acute Respiratory Syndrome Coronavirus

Preparation and characterization of a novel monoclonal antibody specific to severe acute respiratory syndrome-coronavirus nucleocapsid protein

Contact Info

Product

Resources

About