DNA vaccines for farm animals, in particular bovines and porcines

A method for obtaining an immunogenic response comprising administering to a bovine or porcine :

• (a) a DNA vaccine or immunogenic or immunological composition against a pathogen of a bovines or porcines, wherein the DNA vaccine or immunogenic or immunological composition comprises a plasmid containing a nucleotide sequence encoding an immunogen of a pathogen of the bovine or porcine, under conditions allowing the in vivo expression of this sequence, and a cationic lipid containing a quaternary ammonium salt, of formula
• 3
• in which R1 is a saturated or unsaturated linear aliphatic radical having 12 to 18 carbon atoms, R2 is another aliphatic radical containing 2 or 3 carbon atoms, and X a hydroxyl or amine group, this lipid being preferably DMRIE, and optionally, DOPE and/or a GM-CSF protein of the bovine or porcine or a plasmid or expression vector which expresses the GM-CSF;
• and also optionally the nucleotide sequence encoding the immunogen is the sequence of a gene from which the part encoding the transmembrane domain has been deleted and/or the plasmid containing the nucleotide sequence encoding the immunogen also contains a nucleotide sequence encoding a heterologous signal sequence, preferably a tPA and/or the plasmid containing the nucleotide sequence encoding the immunogen also contains a stabilizing intron, preferably intron II of the rabbit beta-globin gene;
• and (b) a conventional (inactivated, attenuated live, subunit) or recombinant vaccine or immunogenic or immunological composition against a bovine or porcine pathogen, wherein (a) and (b) are administered together in a combination, or sequentially, and sequentially can include a prime-boost administration.