To characterize the antigenicity of nucleocapsid proteins (NP) derived from canine coronavirus (CCoV) and canine respiratory coronavirus (CRCoV) in China, the N genes of CCoV (CCoV-BJ70) and CRCoV (CRCoV-BJ202) were cloned from swabs obtained from diseased pet dogs in Beijing and then sequenced. The recombinant NPs (rNPs) were expressed in Escherichia coli and purified by nickel-affinity column and size exclusion chromatography. Sequencing data indicated that the N genes of CCoV-BJ70 and CRCoV-BJ202 belonging to two distinctly different groups were relatively conserved within each subgroup. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results showed that rNPs of CCoV and CRCoV were expressed efficiently and isolated with a final purity of over 95%. Western blot analysis revealed the rNP from CRCoV could cross-react with mice antisera against human coronavirus (HCoV-229E, NL63, OC43, HKU1), while rNP of CCoV had cross-reactivity with only anti-sera against viruses belonging to the same group (HCoV-229E and NL63). In summary, CCoV and CRCoV rNPs were successfully expressed in E. coli and showed antigenic cross-reactivity with antisera raised against human coronaviruses. These findings indicate that further serologic studies on coronavirus infections at the animal-human interface are needed.
【저자키워드】 nucleocapsid protein, cross-reactivity, expression, Canine coronavirus, canine respiratory coronavirus, 【초록키워드】 Coronavirus infection, coronavirus, China, mice, HCoV-229E, canine, NL63, antigenicity, Swab, N gene, group, OC43, HKU1, human coronaviruses, Antisera, Analysis, Escherichia coli, E. coli, sodium dodecyl sulfate, antigenic, Beijing, polyacrylamide gel, Final, size exclusion chromatography, Respiratory Coronavirus, SDS-PAGE, virus, sequenced, cloned, conserved, indicated, raised, expressed, were expressed, purified, cross-react, 【제목키워드】 coronavirus, China, canine, antigenic, Respiratory Coronavirus,