ADE has been reported from the 1980s in feline infectious peritonitis virus (FIPV), an alphacoronavirus highly prevalent among wild and domestic cats. Cats with maternal antibody or received a vaccine against FIP succumbed to virus challenge than did the control animals.
8 It was reported that non-neutralizing monoclonal antibodies (mAbs) or diluted neutralizing mAbs against FIPV spike (S) protein showed enhancement of virus infection while protein A treatment of mAbs prevented enhancement under
in vitro condition.
18 Thus, antibodies against S protein have a role in the development of ADE in FIPV infection. Further, 50% of cats passively immunized with anti-FIPV antibodies developed peritonitis when challenged with the same FIPV serotype.
19 This is a contrasting finding as noted in the dengue virus where ADE occurs between different serotypes.