Needle-free administration of PRRSV vaccines

Abstract

The invention provides novel methods and compositions for the vaccination of porcine animals against porcine reproductive and respiratory syndrome virus (PRRSV). Described herein are immunological and/or vaccine compositions comprising a DNA vector encoding a PRRSV protein, particularly a truncated ORF7 protein, which are administered to porcines using needle-free delivery. The plasmid can include more than one nucleic acid molecule such that the plasmid can express more than one antigen. Also disclosed are methods for using and kits employing such compositions.

1 - 20 . (canceled) 
     
     
         21 . A non-viral DNA plasmid vector comprising a nucleic acid sequence encoding a truncated porcine reproductive and respiratory syndrome virus (PRRSV) ORF7 protein;
 wherein when said plasmid is administered to a suidae animal there is expression in vivo in the suidae animal of the truncated PRRSV ORF7 protein in an effective amount to provide the suidae animal protection from subsequent challenge with a virulent PRRSV;   with the proviso that the truncated ORF7 protein lacks at least ii carboxy terminal amino acids when said truncated ORF7 protein is aligned and compared with a non-truncated PRRSV ORF7 protein having the polypeptide sequence as set forth in SEQ ID NO: 2.   
     
     
         22 . The plasmid of  claim 21 , wherein the encoded truncated PRRSV ORF7 protein has at least 85% homology to the sequence as set forth in SEQ ID NO: 4. 
     
     
         23 . The plasmid of  claim 21 , wherein the nucleic acid sequence consists of a sequence encoding the polypeptide sequence as set forth in SEQ ID NO: 4. 
     
     
         24 . The plasmid of  claim 21 , wherein the truncated PRRSV ORF7 protein is encoded by a sequence having at least 70% homology with the sequence as set forth in SEQ ID NO:3. 
     
     
         25 . The plasmid of  claim 24 , wherein the truncated PRRSV ORF7 protein is encoded by a sequence set forth in SEQ ID NO: 3. 
     
     
         26 . A vaccine comprising the plasmid of  claim 21 . 
     
     
         27 . The vaccine of  claim 26 , further comprising an adjuvant. 
     
     
         28 . The vaccine of  claim 27 , formulated as an oil-in-water emulsion. 
     
     
         29 . The vaccine of  claim 28 , wherein the emulsion is TS6. 
     
     
         30 . The vaccine of  claim 26 , further comprising a pharmaceutically or veterinarily suitable carrier. 
     
     
         31 . The vaccine of  claim 26 , formulated for transdermal administration. 
     
     
         32 . The vaccine of  claim 26 , which is more effective at eliciting in an animal a protective immune response as compared with an otherwise identical vaccine, wherein the PRRSV protein is full-length instead of truncated. 
     
     
         33 . The vaccine of  claim 32 , wherein the full-length protein has the sequence as set forth in SEQ ID NO: 2, and wherein the truncated PRRSV ORF7 protein has the sequence as set forth in SEQ ID NO: 4. 
     
     
         34 . A method of eliciting in a suidae animal a safe and protective immune response against PRRSV comprising administering the vaccine of  claim 26 . 
     
     
         35 . The method of  claim 34 , wherein the animal is a weaned piglet from about 11 to about 24 days of age. 
     
     
         36 . The method of  claim 34 , wherein the vaccine is delivered using a liquid jet needle-free injector. 
     
     
         37 . The method of  claim 36 , wherein the liquid jet needle-free injector is a DERMAVAC™ device. 
     
     
         38 . The method of  claim 34 , wherein the plasmid is a pMASIA-based plasmid. 
     
     
         39 . A vaccination kit or set, comprising a liquid jet needle-free injector and at least one vaccine vial containing the PRRSV vaccine of  claim 26 , operatively assembled to perform the administration of the vaccine to a suidae animal and to elicit a safe and protective immune response against PRRSV. 
     
     
         40 . The kit of  claim 39 , comprising about 100 ng to about 500 μg of the plasmid.