Monoclonal antibodies to bovine coronavirus and their use in enzymoimmunoanalysis and immunochromatography

Two monoclonal antibodies (MAb) to the outer structural protein E2 (spike p eplomeric protein) and two MAb to the inner capsid protein N of bovine coro navirus (BCV) were prepared and identified by Western blotting to be used f or increasing the specificity and sensitivity of BCV detection. The MAb wer e checked by the haernagglutination inhibition test and immunoperoxidase te sts and no cross reactivity with rotavirus was demonstrated by the immunope roxidase test and ELISA. A mixture of all the four MAb at predetermined opt imum concentrations was first used in sandwich ELISA and then, in combinati on with an anti-coronavirus polyclonal antibody, for the development of a s imple and rapid immunochromatographic test (ICT), The results of which can be read visually within 10 min. The inclusion of MAb into ELISA and ICT all ows the detection of both intact and incomplete BCV virions. ELISA and ICT were used in the examination of a set of 74 faecal samples collected from c alves suffering from diarrhoea. ELISA, used as the golden standard verified by electron microscopy, detected BCV in 15 samples (20.3%) and ICT in 16 s amples. Three of the ICT-positive samples were negative by ELISA. On the ot her hand, two of the 58 ICT-negative samples were positive by ELISA. Sensit ivity and specificity of ICT were 94.9% and 86.7%, respectively.