Bacteria over-expressing c-di-AMP and therapeutic methods
The present invention includes the discovery of a strain of Mycobacterium comprising an expression vector encoding a di-adenylate cyclase enzyme. The Mycobacterium is selected from the group consisting of Mycobacterium tuberculosis, Mycobacterium bovis , or a combination thereof and the preferred strain of Mycobacterium is BCG. The preferred expression vector is a mycobacterial expression vector including an hsp60 promoter and a DNA sequence of diadenylate cyclase (disA), or a functional part thereof. The strains of Mycobacterium are used in therapeutic applications including tuberculosis and cancer.
1. A pharmaceutical composition comprising a strain of Mycobacterium selected from the group consisting of Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium bovis bacillus Calmette Guerin BCG, and a combination thereof comprising an expression vector encoding a di-adenylate cyclase enzyme and a pharmaceutically acceptable carrier.
2. The pharmaceutical composition of claim 1 wherein the strain of Mycobacterium is BCG.
3. The pharmaceutical composition of claim 1 wherein the expression vector is a mycobacterial expression vector.
4. The pharmaceutical composition of claim 3 wherein the expression vector comprises the DNA sequence of diadenylate cyclase (disA).
5. The pharmaceutical composition of claim 4 , wherein the disA is that of M. tuberculosis (Rv3586).
6. The pharmaceutical composition of claim 1 wherein the expression vector comprises a hsp60 promoter.
7. The pharmaceutical composition of claim 6 wherein the expression of di-adenylate cyclase enzyme is regulated by the hsp60 promoter.
8. The pharmaceutical composition of claim 1 further comprising at least one or more compounds enhancing immunogenicity.
9. The pharmaceutical composition of claim 8 wherein the at least one or more compounds enhancing immunogenicity is a synthetic c-di-AMP.
10. The pharmaceutical composition of claim 8 wherein the at least one or more compounds enhancing immunogenicity is selected from the group consisting of mycobacterial DNA, IFN, and combinations thereof.