Tuberculosis diagnostic test
A method of diagnosing in a host infection by or exposure to a mycobacterium which expresses ESAT-6 comprising (i) contacting a population of T cells from the host with one or more peptides or analogues selected from the peptides represented by SEQ ID NO:1 to 11 and analogues thereof which can bind a T cell receptor which recognises any of the said peptides, and (ii) determining whether the T cells of said T cell population recognise the peptide(s) and/or analogue(s). The method may performed in vivo. Peptides and a kit which enable the method to be carried out are provided.
1. A method of in vitro diagnosis of Mycobacterium tuberculosis infection in a host, comprising
(a) keeping a population of T cells isolated from said host in contact with a peptide panel comprising one or more epitopes contained within one or more peptides selected from the group consisting of: SEQ ID NO: 1, peptide SEQ ID NO: 2, peptide SEQ ID NO: 3, peptide SEQ ID NO: 4, peptide SEQ ID NO: 5, peptide SEQ ID NO: 6, peptide SEQ ID NO: 7, and peptide SEQ ID NO: 8, and
(b) detecting a recognition response by the T cells to the peptide panel.
2. The method of claim 1 , wherein the peptide panel further comprises one or more epitopes contained within one or more peptides selected from the group consisting of: peptide SEQ ID NO: 9, peptide SEQ ID NO: 10 and peptide SEQ ID NO: 11.
3. The method of claim 1 , wherein the recognition response is a change in the state of the T cells upon contact with the peptide panel.
4. The method of claim 1 , wherein the method yields a diagnostic sensitivity of at least 50%.
5. The method of claim 1 , wherein the T cells are incubated with the peptide panel for between 4 and 24 hours prior to determining the recognition response.
6. The method of claim 1 , wherein the T cells are freshly isolated.
7. The method of claim 1 , wherein the T cells are isolated from blood.
8. The method of claim 1 , wherein the T cells comprise CD4+ and CD8+ T cells.
9. The method of claim 1 , wherein the T cells comprise CD4+ immediate effector T cells.
10. The method of claim 1 , wherein the recognition response is measured by detecting IFNγ production by the T cells.
11. The method of claim 1 , wherein the recognition response is an increase in IFNγ production by the T cells.
12. The method of claim 2 , wherein the method yields a diagnostic sensitivity of at least 50%.
13. The method of claim 2 , wherein the T cells are incubated with the peptide panel for between 4 and 24 hours prior to determining the recognition response.
14. The method of claim 2 , wherein the T cells are freshly isolated.
15. The method of claim 2 , wherein the T cells are isolated from blood.
16. The method of claim 2 , wherein the T cells comprise CD4+ and CD8+ T cells.
17. The method of claim 2 , wherein the T cells comprise CD4+ immediate effector T cells.
18. The method of claim 2 , wherein the recognition response is measured by detecting IFNγ production by the T cells.
19. A method of in vitro diagnosis of Mycobacterium tuberculosis infection in a host, comprising
(a) keeping a population of T cells isolated from said host in contact with a peptide panel comprising one or more epitopes contained within one or more peptides selected from the group consisting of: SEQ ID NO: 1, peptide SEQ ID NO: 2, peptide SEQ ID NO: 3, peptide SEQ ID NO: 4, peptide SEQ ID NO: 5, peptide SEQ ID NO: 6, peptide SEQ ID NO: 7, and peptide SEQ ID NO: 8, peptide SEQ ID NO: 9, peptide SEQ ID NO: 10 and peptide SEQ ID NO: 11, and
(b) detecting a recognition response by the T cells to the peptide panel.
20. The method of claim 19 , wherein the recognition response is a change in the state of the T cells upon contact with the peptide panel.