Vet Pathol Email Content Delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Poncelet, L.
Right arrow Articles by Kadhim, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Poncelet, L.
Right arrow Articles by Kadhim, H.
Vet Pathol 45:140-153 (2008)
© 2008 American College of Veterinary Pathologists
INFECTIOUS DISEASE

Detection of Antigenic Heterogeneity in Feline Coronavirus Nucleocapsid in Feline Pyogranulomatous Meningoencephalitis

L. Poncelet, A. Coppens, D. Peeters, E. Bianchi, C. K. Grant4 and H. Kadhim

Anatomy/Embryology Department, Faculty of Medicine, Free University of Brussels, Bruxelles, Belgium (LP, AC), Clinical Sciences Department, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium (DP), Animal Health Department, Faculty of Veterinary Medicine, University of Parma, Parma, Italy (EB), 4 Custom Monoclonals International, Sacramento, CA (CG), and Anatomic Pathology Department; Neuropathology Unit, Brugmann University Hospital and Children Hospital, Free University of Brussels, Bruxelles, Belgium (HK)

Abstract

A new monoclonal antibody (mAb), CCV2-2, was compared with the widely used FIPV3-70 mAb, both directed against canine coronavirus (CCoV), as a diagnostic and research tool. Western blot showed that both anti-CCoV mAbs only reacted with a protein of 50 kD, a weight consistent with the feline coronavirus (FCoV) viral nucleocapsid. A competitive inhibition enzyme-linked immunosorbent assay showed that the 2 recognized epitopes are distinct. Preincubation of CCV2-2 mAb with FCoV antigen suppressed the immunostaining. Formalin-fixed, paraffin-embedded sections from brains of 15 cats with the dry form of feline infectious peritonitis (FIP) were examined by immunohistochemistry. Immunohistochemistry was performed with both anti-CCoV mAbs, either on consecutive or on the same sections. A myeloid-histiocytic marker, MAC 387, was also used to identify FIP virus–infected cells. In all regions where MAC 387–positive cells were present, positive staining with the CCV2-2 mAb was systematically detected, except at some levels in 1 cat. In contrast, none or only a few cells were positive for the FIPV3-70 mAb. Double immunostaining showed macrophages that were immunopositive for either CCV2-2 alone or alternatively for CCV2-2 and FIPV3-70 mAbs. This reveals the coexistence of 2 cohorts of phagocytes whose FIP viral contents differed by the presence or absence of the FIPV3-70–recognized epitope. These findings provide evidence for antigenic heterogeneity in coronavirus nucleocapsid protein in FIP lesions, a result that is in line with molecular observations. In addition, we provide for the first time morphologic depiction of viral variants distribution in these lesions.

Key words: Antigenic heterogeneity; cats; coronavirus; FIP; meningoencephalitis.

Request reprints from L. Poncelet, Anatomy/Embryology Department, CP 619, Faculty of Medicine, Free University of Brussels, Route de Lennik, 808, B-1070 Bruxelles (Belgium). E-mail: lcponce{at}ulb.ac.be






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by the American College of Veterinary Pathologists.