Mouse hepatitis virus spike and nucleocapsid proteins expressed by adenovirus vectors protect mice against a lethal infection

• Published in: Journal of general virology 1993-10, Vol.74 (10), p.2061-2069
• Main Authors: Wesseling, John G, Godeke, Gert-Jan, Schijns, Virgil E. C. J, Prevec, Ludvik, Graham, Frank L, Horzinek, Marian C, Rottier, Peter J. M
• Format: Article
• Language: English
• Subjects: Adenoviruses, Human; Animalia; Animals; Antibodies, Viral - blood; Biological and medical sciences; Capsid - genetics; Capsid - immunology; Cloning, Molecular; Coronavirus Infections - immunology; Coronavirus Infections - veterinary; Female; Fundamental and applied biological sciences. Psychology; Genes, Viral - genetics; Genetic Vectors; HeLa Cells; Hepatitis, Viral, Animal - immunology; Humans; Membrane Glycoproteins; Mice; Mice, Inbred BALB C; Microbiology; Murine hepatitis virus - genetics; Murine hepatitis virus - immunology; Recombination, Genetic; Spike Glycoprotein, Coronavirus; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies; Viral Core Proteins - genetics; Viral Core Proteins - immunology; Viral Envelope Proteins - genetics; Viral Envelope Proteins - immunology; Virology
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/0022-1317-74-10-2061

1 Institute of Virology, Veterinary Faculty, Utrecht University, P.O. Box 80.165, 3508 TD Utrecht, The Netherlands and 2 Departments of Biology and Pathology, McMaster University, Hamilton, Ontario, Canada Infection with the mouse hepatitis coronavirus (MHV) provides an excellent model for the study of viral diseases of the central nervous system and the gastrointestinal tract. With the ultimate aim of studying mucosal immunity to MHV we have cloned the genes encoding the structural proteins of MHV strain A59 (MHV-A59) into the E3 region of a human adenovirus type 5 vector. Infection of HeLa cells with the resulting recombinant adenoviruses AdMHVS, AdMHVN and AdMHVM revealed the correct expression of the spike (S), nucleocapsid (N) and membrane (M) proteins, respectively. Intraperitoneal inoculation of BALB/c mice with the recombinant viruses elicited serum antibodies which specifically recognized the respective MHV proteins in an immunoprecipitation assay. Only antibodies to the S protein neutralized MHV-A59 in vitro but titres were low. When analysed by ELISA or by immunofluorescence only the antibody response to the N protein was significant; weak responses or no detectable response at all were found for S and M, respectively. Upon intracerebral challenge with a lethal dose of MHV-A59 we found that a significant fraction of animals vaccinated with adenovirus vectors expressing either the S protein or N protein were protected. This protective effect was significantly stronger when the animals were given a booster immunization with the same vector prior to challenge. No protection was induced by AdMHVM. Interestingly, enhanced protection resulted when AdMHVS and AdMHVN were applied in combination as compared to survival after single immunizations. The results indicate that both the N and S proteins generate a protective immune response and suggest that this response is enhanced by combined expression of the two proteins. Present address: Department of Endocrinology and Reproduction, Medical Faculty, Erasmus University of Rotterdam, Rotterdam, The Netherlands. Received 25 March 1993; accepted 8 June 1993.