Serum inhibitor of coronaviruses OC43 and NCDCV: a study in vivo

It is well known that some strains of coronaviruses, such as human OC43 and bovine NCDCV, are highly inhibited by non antibody factors present in sera of different mammalian species and sensitive to phospholipase-C treatment. So far this inhibitor has only been revealed in vitro experimental procedures with coronavirus strains adapted to growth in human lung fibroblast cell cultures. The purpose of this work was to ascertain whether this inhibiting activity was also effective "in vivo". In order to detect the "in vivo" activity, we used suckling mice which have been shown to be the animals most sensitive to infection with these viruses. Our results demonstrated that the same non antibody inhibitor is able to neutralize viral infection both "in vivo" and "in vitro".