Genome- and HLA- Wide Scanning and Validation of Cytotoxic CD8 T Cell Responses against Mycobacterium Tuberculosis
Summary:
Vaccines against tuberculosis are urgently needed. CD4 T cell responses play
a major role in the generation of acquired immunity against M. tuberculosis.
However, it is increasingly recognised that CD8 cytotoxic T cells (CTL) also
contribute to optimal host defence against mycobacteria. Unfortunately,
relatively few CTL responses against TB have been identified. The object of this
proposal is to perform a complete antigen- and epitope- discovery of relevance
for human immune CTL responses against M. tuberculosis. Several recently
established innovative high-throughput methods from immunology and
bioinformatics will be combined. Two different screening approaches will be
used; one of ‘forward antigen discovery’, where expression libraries
representing the whole M. tuberculosis genome will be screened for proteins that
are targets for CTL responses in TB patients, and one of ‘reverse antigen
discovery’, where proteins, which are likely to contain CTL epitopes, are
predicted using computational methods, pre-validated by binding to relevant HLA
molecules, and finally validated using CTL response from TB patients. The
strategy will initially be to perform a genome-wide identification of novel
target proteins. Within these proteins, we will subsequently perform HLA-wide
epitope discovery where epitopes restricted by one of the major HLA supertypes
are predicted, pre-validated for HLA binding and tested for CTL responses in TB
patients.
Background:
Infectious diseases remain the largest cause of death in the world. Among
infectious diseases, tuberculosis is responsible for the greatest number of
deaths. Each year, 54 million people are infected with Mycobacterium
tuberculosis, 6.8 million develop clinical disease and 2.4 million people
die of tuberculosis. Tuberculosis is responsible for 5% of all deaths worldwide.
There is mounting evidence from animal studies that CD8 T cells are involved in
the control of latent M. tuberculosis infection. However,
relatively little has been published on the functional role of
mycobacteria-specific CD8 T cells in humans, nor on the actual mycobacterial
antigens and epitopes targeted by these killer cells.
Aim:
The aims of this project are:
- to evaluate the CD8 cytotoxic T cell response repertoire in the human
population
- to test if expression libraries representing the whole M. tuberculosis
genome can be used for CTL antigen discovery
- to test the use of immuno-bioinformatics is a fast and rational approach to
CTL epitope identification
Expected results:
Firstly, this project expects to find new CTL epitopes. More specifically, it
will:
- identify proteins likely to be good antigens, using expression cloning of M.
tuberculosis antigens and M. tuberculosis–derived epitopes seen by patient
CTL’s
- predict which peptides are potential CTL epitopes within all M. tuberculosis
proteins for all major human HLA supertypes and select a fraction of these for
actual synthesis and test
- measure binding to HLA molecules for the predicted peptides
- measure CTL responses against predicted epitopes in M. tuberculosis infected
persons and BCG vaccinated individuals using either target cells transfected
with the M. tuberculosis expression library + relevant HLA molecules, or target
cells pulsed with identified peptides.
Potential applications:
The results obtained in this project can be used in the development of a
vaccine against TB.
Coordinator:
Ole Lund
Technical University of Denmark, Centre for Biological Sequence Analysis
Building 208
2800 Lyngby
Denmark
Tel: +45 4525 2425
Fax: +45 4593 1585
E-mail: lund@cbs.dtu.dk
Website: http://www.cbs.dtu.dk
Partners:
| Nº |
Principal
Scientific
Participants |
Official Address |
Other Information |
| 2 | Søren Buus | Institute for Medical Microbiology and Immunology Panum 18.3.12
Blegdamsvej 3
DK-2200 Copenhagen N
Denmark | Tel: +45 3532 7885
Fax: +45 3532 7853
E-mail: S.Buus@immi.ku.dk |
| 3 | Tom H.M. Ottenhoff | Department Immunohematology and Blood Transfusion
Leiden University Medical Center
Albinusdreef 2,
NL-2333 ZA Leiden
The Netherlands | Tel:
+31 71 5265128 (secr);
5263809 (desk)
Fax: +31 71 5216751
E-mail: t.h.m.ottenhoff@lumc.nl
|
| 4 | Ugur Sahin | Pharmaceuticals AG, Germany
Freiligrathstr. 12
DE-55131 Mainz
Germany | Tel: +49 6131 1440100
Fax: +49 6131 1440111
E-mail:
v.schlueter@ganymed-pharmaceuticals.com
|
