Mucosal immunization against ovine lentivirus using PEI-DNA complexes and modified vaccinia Ankara encoding the gag and/or env genes.

R. D. Reina (1) , C. Barbezange (2) , H. Niesalla (3) , X. de Andrés (1) , H. Arnarson (4) , E. Biescas (5) , M. Mazzei (6) , C. Fraisier (7) , T. N. Mcneilly (3) , C. Liu (3) , Michel Perez (5) , M. L. Carrozza (6) , P. Bandecchi (8) , C. Solano (1) , H. Crespo (1) , I. Glaria (1) , C. Huard (9) , D. J. Shaw (3) , I. de Blas (5) , D. de Andrés (1) , F. Tolari (6) , S. Rosati (8) , M. Suzan-Monti (7) , V. Andrésdottir (4) , S. Torsteinsdottir , G. Petursson (10) , L. Lujan (5) , Michel Pépin (9, 11) , B. Amorena (1) , B. Blacklaws (2) , G. D. Harkiss (3)

1 UPNA - Universidad Pública de Navarra [Espagne] = Public University of Navarra
2 CAM - University of Cambridge [UK]
3 University of Edinburgh
4 University of Iceland [Reykjavik]
5 University of Zaragoza - Universidad de Zaragoza [Zaragoza]
6 University of Pisa - Università di Pisa
7 AMU MED - Aix-Marseille Université - Faculté de médecine
8 UNITO - Università degli studi di Torino = University of Turin
9 LERPRA - Laboratoire d'études et de recherches sur les petits ruminants et les abeilles
10 Department of Maths Sciences
11 AFSSA - Agence Française de Sécurité Sanitaire des Aliments

Sheep were immunized against Visna/Maedi virus (VMV) gag and/or env genes via the nasopharynx-associated lymphoid tissue (NALT) and lung using polyethylenimine (PEI)-DNA complexes and modified vaccinia Ankara, and challenged with live virus via the lung. env immunization enhanced humoral responses prior to but not after VMV challenge. Systemic T cell proliferative and cytotoxic responses were generally low, with the responses following single gag gene immunization being significantly depressed after challenge. A transient reduction in provirus load in the blood early after challenge was observed following env immunization, whilst the gag gene either alone or in combination with env resulted in significantly elevated provirus loads in lung. However, despite this, a significant reduction in lesion score was observed in animals immunized with the single gag gene at post-mortem. Inclusion of IFN-gamma in the immunization mixture in general had no significant effects. The results thus showed that protective effects against VMV-induced lesions can be induced following respiratory immunization with the single gag gene, though this was accompanied by an increased pulmonary provirus load.

Keywords: sheep; lentivirus; DNA vaccination; mucosal

Domains: Vaccinology

R. D. Reina, C. Barbezange, H. Niesalla, X. de Andrés, H. Arnarson, et al.. Mucosal immunization against ovine lentivirus using PEI-DNA complexes and modified vaccinia Ankara encoding the gag and/or env genes.. Vaccine, 2008, 26 (35), pp.4494-505. ⟨10.1016/j.vaccine.2008.06.065⟩. ⟨hal-00365995⟩