Adjuvant compositions and methods for enhancing immune responses to polynucleotide-based vaccines

#Field of the Invention

#The present invention relates generally to adjuvants, immunogenic compositions, and methods useful for polynucleotide-based vaccination. The present invention provides compositions and methods useful for enhancing immune response, especially the humoral immune response of vertebrates to polynucleotide-based vaccines. In particular, the present invention provides an adjuvant of cytofectin:co-lipid mixture wherein the cytofectin is (±)-N-(3-aminopropyl)-N,N-dimethyl-2,3-bis(syn-9-tetradeceneyloxy)-1-propanaminium bromide (GAP-DMORIE).

#In the late 1980s, it was discovered that direct intramuscular (i.m.) injection of lipid-DNA complexes results in measurable protein expression, and that “naked” plasmid DNA (pDNA) is taken up and expressed in muscle to a greater extent than lipid-DNA complexes (Felgner, Scientific American, 276(6), 102-106 (1997)).

#The foregoing aspects and advantages of the present invention will be readily apparent to one skilled in the art upon reference to the figures and the detailed description which follows.

#FIG. 1 illustrates the diagrams of Plasmid DNAs. Each vector has a pUC19 origin of replication and a kanamycin resistance gene for plasmid growth in E. coli bacteria. CMV=human cytomegalovirus promoter and enhancer; CMV-A=human cytomegalovirus intron A; mRGB=modified rabbit β-globin polyadenylation signal; BGH=bovine growth hormone polyadenylation signal.

#FIG. 2 illustrates the chemical structures for the cytofectin GAP-DMORIE and the co-lipids DOPE and DPyPE, along with structurally related cytofectins.

#It will be apparent to one skilled in the art, in view of the following detailed description and the claims appended hereto, that various substitutions and modifications may be made to the present invention without departing from the scope of the invention as claimed.

#The present invention is directed to the polynucleotide-based immunization of a vertebrate, to protect from or treat a vertebrate with a disease condition. The present invention includes the use of cytofectin, especially GAP-DMORIE in adjuvants, immunogenic compositions, and methods for immunizing a vertebrate, especially with polynucleotude-based immunogen.

#The adjuvant composition of the present invention includes one or more cytofectins and, in preferred embodiments, one or more co-lipids. Cytofectins are cationic lipids. In one embodiment, cytofectin is GAP-DMORIE, which has a structure corresponding to a 2,3-dialkoxy-propanaminium skeleton possessing a unique combination of two linear fourteen-carbon mono-unsaturated alkyl chains and a propylamine substituent on the quaternary nitrogen (See FIG. 2).