Immunogenic lipopeptides comprising T-helper and cytotoxic T-lymphocyte (CTL) epitopes

1. A lipopeptide comprising a polypeptide conjugated to one or more lipid moieties wherein:

(i) said polypeptide comprises an amino acid sequence wherein the linkages between the amino acids making up the amino acid sequence consist of alpha-amino acid linkages and the amino acid sequence comprises:

(a) the amino acid sequence of a T helper cell (Th) epitope and the amino acid sequence of a cytotoxic T cell (CTL) epitope, wherein said amino acid sequences are different; and

(b) one or more internal lysine residues or internal lysine analog residues for covalent attachment of each of said lipid moieties via the epsilon-amino group or terminal side-chain group of said lysine or lysine analog; and

(ii) each of said one or more lipid moieties is covalently attached to an epsilon-amino group of said one or more internal lysine residues or to a terminal side-chain group of said one or more internal lysine analog residues, wherein an internal lysine residue or internal lysine analog residue to which a lipid moiety is attached is positioned in the polypeptide amino acid sequence between the Th epitope and the CTL epitope.

2. The lipopeptide of claim 1 wherein the lipid moiety has a structure of General Formula (VII):

wherein:

(i) X is selected from the group consisting of sulfur, oxygen, disulfide (—S—S—), and methylene (—CH 2 —), and amino (—NH—);

(ii) m is an integer being 1 or 2;

(iii) n is an integer from 0 to 5;

(iv) R 1 is selected from the group consisting of hydrogen, carbonyl (—CO—), and R′—CO— wherein R′ is selected from the group consisting of alkyl having 7to 25 carbon atoms, alkenyl having 7 to 25 carbon atoms, and alkynyl having 7 to 25 carbon atoms, wherein said alkyl, alkenyl or alkynyl group is optionally substituted by a hydroxyl, amino, oxo, acyl, or cycloalkyl group;

(v) R 2 is selected from the group consisting of R′—CO—O—, R′—O—, R′—O—CO—, R′—NH—CO—, and R′—CO—NH—, wherein R′ is selected from the group consisting of alkyl having 7 to 25 carbon atoms, alkenyl having 7 to 25carbon atoms, and alkynyl having 7 to 25 carbon atoms, wherein said alkyl, alkenyl or alkynyl group is optionally substituted by a hydroxyl, amino, oxo, acyl, or cycloalkyl group; and

(vi) R 3 is selected from the group consisting of R′—CO—O—, R′—O—, R′—O—CO—, R′—NH—CO—, and R′—CO—NH—, wherein R′ is selected from the group consisting of alkyl having 7 to 25 carbon atoms, alkenyl having 7 to 25carbon atoms, and alkynyl having 7 to 25 carbon atoms, wherein said alkyl, alkenyl or alkynyl group is optionally substituted by a hydroxyl, amino, oxo, acyl, or cycloalkyl group;

and wherein each of R 1 , R 2 and R 3 are the same or different.

3. The lipopeptide of claim 2 wherein X is sulfur; m and n are both 1; R 1 is selected from the group consisting of hydrogen, and R′—CO—, wherein R′ is an alkyl group having 7 to 25 carbon atoms; and R 2 and R 3 are selected from the group consisting of R′—CO—O—, R′—O—, R′—O—CO—, R′—NH—CO—, and R′—CO—NH—, wherein R′ is an alkyl group having 7 to 25 carbon atoms.

4. The lipopeptide of claim 3 wherein R′ is selected from the group consisting of: palmitoyl, myristoyl, stearoyl, lauroyl, octanoyl, decanoyl, and cholesterol.

5. The lipopeptide of claim 2 wherein the lipid is contained within a lipoamino acid moiety selected from the group consisting of: Pam 1 Cys, Pam 2 Cys, Pam 3 Cys, Chol 2 Lys, Ste 2 Cys, Lau 2 Cys, and Oct 2 Cys.

6. The lipopeptide of claim 1 wherein the lipid moiety has the following General Formula (VIII):

wherein:

(i) R 4 is selected from the group consisting of: (i) an alpha-acyl-fatty acid residue consisting of between about 7 and about 25 carbon atoms; (ii) an alpha-alkyl-beta-hydroxy-fatty acid residue; (iii) a beta-hydroxy ester of an alpha-alkyl-beta-hydroxy-fatty acid residue; and (iv) a lipoamino acid residue; and

(ii) R 5 is hydrogen or the side chain of an amino acid residue.

7. The lipopeptide of claim 1 wherein the lipid moiety is separated from the peptide moiety by a spacer.

8. The lipopeptide of claim 7 wherein the spacer comprises arginine, serine or 6-aminohexanoic acid.

9. The lipopeptide of claim 1 wherein the T-helper epitope is a T-helper epitope of influenza virus haemagglutinin or a T-helper epitope of canine distemper virus F (CDV-F) protein.

10. The lipopeptide of claim 9 wherein the T-helper epitope of influenza virus haemagglutinin comprises the amino acid sequence set forth in SEQ ID NO: 1.

11. The lipopeptide of claim 9 wherein the T-helper epitope of CDV-F protein comprises the amino acid sequence set forth in SEQ ID NO: 20.

12. The lipopeptide of claim 1 wherein the CTL epitope is from an immunogenic protein, lipoprotein, or glycoprotein of a virus.

13. The lipopeptide according to claim 12 wherein the virus is influenza virus.

14. The lipopeptide according to claim 12 wherein the virus is hepatitis C virus.

15. The lipopeptide of claim 1 wherein the CTL epitope is from an immunogenic protein, lipoprotein, or glycoprotein of a prokaryotic organism.

16. The lipopeptide of claim 1 wherein the CTL epitope is from an immunogenic protein, lipoprotein, or glycoprotein of a eukaryotic organism.

17. The lipopeptide according to claim 16 wherein the CTL epitope is from an ovalbumin protein of a mammal or a tumor cell.

18. A composition comprising the lipopeptide of claim 1 and a pharmaceutically acceptable excipient or diluent.