An ELISA based on recombinant spike protein S for detection of antibodies to transmissible gastroenteritis virus of swine (TGEV)-like canine coronaviruses

Recombinant canine coronaviruses, resembling the transmissible gastroenteritis virus of swine (TGEV) in a 5' fragment of the S glycoprotein, have been detected recently and showed to be present in canine populations. The 5'fragment of the S protein (S') of a TGEV-like canine coronavirus (MV), strain 174/06, was expressed in an Escherichia coli cell-free system. The purified recombinant polypeptide was employed to develop an ELISA test for the detection of TGEV-like CCoV-specific antibodies in dog sera. Four canine sera positive for TGEV-like CCoV, six sera positive to classical CCoV-II strains and 10 negative control sera were examined. The recombinant S' was not recognized by antibodies to classical CCoV-II, as only sera from dogs infected experimentally with TGEV-like CCoV reacted strongly with the recombinant S' polypeptide whereas dog sera with antibodies to classical CCoV-II did not react. As classical CCoV-II and TEGV-like CCoVs are related antigenically, the recombinant S' ELISA is a useful method to investigate serologically the prevalence of TGEV-like CCoVs in dogs

Severe enteritis in Italian Mediterranean buffalo calves associated with a novel bovine-like coronavirus

An outbreak of severe enteritis in Italian Mediterranean buffalo calves is reported, which was associated to infection by a novel bovine-like coronavirus (CoV). By conventional and real-time RT-PCR assays for bovine-like CoVs, the virus was demonstrated in the intestinal contents of two 20-day-old buffalo calves that died of a severe form of enteritis, as well as in the fecal specimens of additional 17 buffalo calves with diarrhea. Biological and genetic characterization showed that the bubaline strain can be considered as prototype of a novel group 2 CoV, namely bubaline CoV (BuCoV)