Fusion of heterooligomeric mycobacterial antigens
The present invention relates generally to novel immunogenic combinations comprising or encoding at least two heterooligomeric mycobacterial antigens and preferably a fusion polypeptide comprising said two heterooligomeric mycobacterial antigens, where the mycobacterial antigens are selected from the group of Esx, PE and PPE antigens of a Mycobacterium species, particularly a Mycobacterium of the tuberculosis complex such as Mycobacterium tuberculosis (Mtb). The present invention also relates to vectors, host cells and compositions comprising or encoding said immunogenic combination as well as to methods for expressing and producing it. The present invention also relates to methods of using said immunogenic combination, fusion polypeptide, vector, host cell, composition particularly for inducing or stimulating an immune response with the goal of providing a protective response against a Mycobacterium infection or any disease caused by or associated with a Mycobacterium infection.
1. A viral vector comprising:
a nucleic acid molecule encoding a fusion of the heterooligomeric mycobacterial antigens ESAT6 with CFP10, and
nucleic acid molecule(s) encoding one or more additional mycobacterial antigen(s) selected from the group consisting of Ag85B (Rv1886), RpfB, RpfD, Rv1813, Rv2626, Rv3407, and a mycobacterial antigen comprising an amino acid sequence as set forth in SEQ ID NO: 3 or 4.
2. The viral vector of claim 1 , wherein said vector is a poxvirus vector selected from the group consisting of fowlpox, canarypox and vaccinia virus vector.
3. The viral vector according to claim 1 which is selected from the group consisting of:
(i) A viral vector comprising:
a) a nucleic acid molecule encoding a fusion comprising heterooligomeric mycobacterial antigens ESAT-6 and CFP10,
b) a nucleic acid molecule encoding Ag85B, and
c) a nucleic acid molecule encoding Rv2626; and
(ii) A viral vector comprising:
a) a nucleic acid molecule encoding a fusion comprising heterooligomeric mycobacterial antigens ESAT-6 and CFP10;
b) a nucleic acid molecule encoding a fusion comprising heterooligomeric mycobacterial antigens TB10.4 and TB9.8,
c) a nucleic acid molecule encoding a fusion polypeptide comprising the additional mycobacterial antigens Rv2626 and Ag85B;
d) a nucleic acid molecule encoding a fusion polypeptide comprising the additional mycobacterial antigens RpfB and RpfD; and
e) a nucleic acid molecule encoding a fusion polypeptide comprising the additional mycobacterial antigens Rv3407 and Rv1813.
4. The viral vector according to claim 1 , wherein said nucleic acid molecules are placed under the transcriptional control of a one or more promoter(s) suitable for ensuring expression of the encoded fusion and additional mycobacterial antigen(s) in a mammalian cell.
5. A host cell comprising the viral vector according to claim 1 .
6. A composition comprising at least one of the viral vector of claim 1 or at least one of the host cell of claim 5 .
7. The composition of claim 6 , wherein the composition further comprises a pharmaceutically acceptable vehicle.
8. A method for treating a Mycobacterium infection, or any disease and pathologic condition caused by or associated with such a Mycobacterium infection, in a subject in need thereof, comprising the step of administering a therapeutically effective amount of the composition of claim 6 to the subject.
9. A method for delaying the risk of infection with a Mycobacterium in a subject in need thereof, comprising the step of administering a therapeutically effective amount of the composition of claim 6 to the subject.
10. The method of claim 8 , for treating an active disease in a subject infected with a Mycobacterium species.
11. The method of claim 8 , for treating reactivation in a subject latently infected with a Mycobacterium.
12. The method of claim 8 , wherein the subject has previously been immunized with Bacille-Calmette-Guerin (BCG).
13. The method of claim 8 , further comprising the administration of one or more chemotherapeutic drug(s) effective against a Mycobacterium infection.
14. The method of claim 8 , for inducing or enhancing an immune response in the administered subject.
15. The method of claim 14 , wherein said induced or stimulated immune response is a CD4+ and/or CD8+-mediated T cell response directed to a mycobacterial antigen/epitope.
16. The viral vector according to claim 1 , further comprising nucleic acid molecule(s) encoding a fusion of the heterooligomeric mycobacterial antigens TB10.4 (Rv0288) with TB9.8 (Rv0287).
17. The viral vector according to claim 1 , further comprising nucleic acid molecule(s) encoding one or more other additional mycobacterial antigen(s).
18. The viral vector according to claim 1 , wherein said vector comprises a nucleic acid molecule encoding a fusion of the heterooligomeric mycobacterial antigens ESAT6 with CFP10, and
a) nucleic acid molecule(s) encoding mycobacterial antigens Rv2626 and Ag85B; or
b) a nucleic acid molecule(s) encoding a fusion of the heterooligomeric mycobacterial antigens TB10.4 and TB9.8 and nucleic acid molecule(s) encoding mycobacterial antigens Rv2626, Ag85B, RpfB, RpfD, Rv3407 and Rv1813.
19. The viral vector according to claim 1 , wherein said additional mycobacterial antigen(s) are encoded in the form of separate polypeptides and/or in the form of fusion of two.
20. The viral vector according to claim 19 , wherein said fusion polypeptide of additional mycobacterial antigens comprises (i) Rv2626 and Ag85B, (ii) RpfB and RpfD, or (iii) Rv3407 and Rv1813.
21. The viral vector according to claim 20 , wherein said fusion polypeptide of additional mycobacterial antigens comprises:
a) one or more peptide(s) to ensure appropriate folding of said mycobacterial antigens such as a protease cleavage site inserted between the upstream and downstream polypeptides of said fusion polypeptide; or
b) an amino acid sequence exhibiting at least 70% identity with any of the amino acid sequences shown in SEQ ID NO: 8 to SEQ ID NO: 12.
22. A composition comprising at least one viral vector according to claim 21 .
23. A method of treating a Mycobacterium infection in a subject in need thereof, comprising administering a therapeutically effective amount of a composition comprising the vector of claim 21 to the subject.