A single immunization with a minute dose of a lentiviral vector-based vaccine is highly effective at eliciting protective humoral immunity against West Nile virus.
BACKGROUND
Lentiviral vectors, due to their capacity to transduce non-dividing cells, have become precious and worldwide used gene transfer systems. Their ability to efficiently and stably transduce dendritic cells (DCs) has led to their successful use as vaccination vectors for eliciting strong, specific and protective cellular immune responses mostly in anti-tumoral but also in anti-viral applications. However, the ability of lentiviral vectors to elicit an antibody-based protective immunity has, to date, not been evaluated. In the present study, we evaluated the potential of a lentiviral vector-based vaccine to elicit humoral immunity against West Nile virus (WNV). WNV is a mosquito-borne flavivirus that emerged in North America and causes encephalitis in humans, birds and horses. Neutralizing anti-WNV antibodies have been shown to be crucial for protection against WNV encephalitis.


METHODS
The ability of lentiviral vector TRIP/sE(WNV), expressing the secreted soluble form of the envelope E-glycoprotein (sE(WNV)) from the highly virulent IS-98-ST1 strain of WNV, to induce a specific humoral response and protection against WNV infection was assessed in a mouse model of WNV encephalitis.


RESULTS
Remarkably, a single immunization with a minute dose of TRIP/sE(WNV) was efficient at eliciting a long-lasting, protective and sterilizing humoral immunity, only 1 week after priming.


CONCLUSIONS
This study broadens the applicability of lentiviral vectors as efficient non-replicating vaccines against pathogens for which a neutralizing humoral response is one active arm of the protective immunity. The TRIP/sE(WNV) lentiviral vector appears to be a promising tool for veterinary vaccination against zoonotic WNV.
Iglesias
Maria Candela
MC
Groupe de Virologie Moléculaire et Vectorologie, Institut Pasteur, 28 rue du Dr. Roux. 75724 Paris Cedex 15, France.
Frenkiel
Marie-Pascale
MP
Mollier
Karine
K
Souque
Philippe
P
Despres
Philippe
P
Charneau
Pierre
P
D000818:Animals; D000917:Antibody Formation; D005822:Genetic Vectors; D006801:Humans; D007115:Immunization Schedule; D016086:Lentivirus / Q000235:genetics*; D051379:Mice; D014161:Transduction, Genetic; D014759:Viral Envelope Proteins; D014765:Viral Vaccines / Q000276:immunology*; D014901:West Nile Fever / Q000276:immunology* / Q000517:prevention & control*; D014902:West Nile virus / Q000276:immunology / Q000472:pathogenicity*
D014759:Viral Envelope Proteins; D014765:Viral Vaccines