ANTIVIRAL ACTIVITY OF BOVINE COLLECTINS AGAINST ROTAVIRUSES

The antiviral activity against rotaviruses of three bovine collectins, conglutinin, collectin-43 (CL-43) and bovine SP-D, was examined. As s hown by ELISA and Western blot, all three collectins bound to the Nebr aska calf diarrhoea virus bovine strain of rotavirus, and specifically to the VP7 glycoprotein. Inhibition by mannose or EDTA confirmed that binding was mediated through the lectin domains of the collectins, Bi nding resulted in haemagglutination inhibition and neutralization of r otavirus infectivity, CL-43 displaying the highest activity in both ty pes of assay. In contrast, conglutinin was the most potent of the thre e collectins against influenza virus A/HKx31. Neutralization of rotavi ruses by the lectins was dependent on glycosylation of VP7, Furthermor e, rotaviruses adapted to growth in Madin-Darby bovine kidney cells, a nd thus bearing carbohydrate of bovine origin, remained sensitive to n eutralization, although slightly less so than virus stocks propagated in the monkey kidney cell line MA 104. These findings provide the firs t description of antiviral activity of collectins against a nonenvelop ed virus and may indicate a potential role for collectins in host defe nce against bovine rotavirus infection.