Protective effects of intranasal immunization with recombinant glycoprotein in the BALB/c mouse model of Equine herpesvirus 1 infection

FUENTEALBA N, SGUAZZA G, ZANUZZI C, SCROCHI M, BRAVI M, CID DE LA PAZ V,, VALERA A,CORVA S, BARBEITO C, GIMENO E, PECORARO M, GALOSI C

Berlin

Congreso; 32nd Meeting of the European Society of Veterinary Pathology 12th Meeting of the European Society of Toxicologic Pathology 25th Meeting of the European College of Veterinary Pathology 27th ? 30th August 2014, Berlin, Germany; 2014

European Society of Veterinary Pathology

Introduction: Equine Herpesvirus 1 (EHV-1) causes abortion, respiratory and neurological disorders in horses. Natural respiratory infection and immunoprophilaxis do no provide long-lived protection. We evaluated the protection conferred by a purified baculovirus-expressed glycoprotein D (gD) to BALB/c mice challenged with the Argentinean AR8 EHV-1 strain. Material and Methods: Thirteen groups of BALB-c mice were immunized with gD (two doses of 15 μg each) or phosphate buffered saline (control groups) using parental or intranasal (IN) routes and Complete Freund, Specol or Montanide, as adjuvants. Immunoglobulin G (IgG) detection and virus neutralization was determined in pool blood samples. Mice were challenged with ~106.3 TCID50/ 50 μl of EHV-1 AR8 by IN route. Infectivity titration, histopathological and immunohistochemical studies were done in lungs. Results: Mice immunized by parenteral routes showed clinical signs, positive virus isolation, lesion in lungs, and an effective IgG response. After IN immunization no clinical sign was observed, virus isolation was negative, no lesion or viral antigens were detected. The IgG response was not efficient, but IgA was detected in bronchiolar epithelium. Conclusions: Our results support the IN immunization to prevent the virus entry to the lungs and provide novel information with respect to immunization routes.