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Enzyme-linked Immunospot Assay (ELISPOT): Quantification of Th-1 Cellular Immune Responses Against Microbial Antigens
Published on: November 24, 2010
Human T cell responses to the ESAT-6 antigen from Mycobacterium tuberculosis
1Department of Tuberculosis Immunology, Statens Serum Institut, 2300 Copenhagen 5, Denmark. tbimm@ssi.dk
The Journal of Infectious Diseases
|February 10, 1999
Summary
Tuberculosis patients and healthy contacts frequently show T cell responses to ESAT-6, a key antigen in tuberculosis. This antigen
Area of Science:
- Immunology
- Infectious Diseases
- Tuberculosis Research
Background:
- Tuberculosis (TB) remains a global health challenge.
- Identifying reliable diagnostic markers for TB is crucial for early detection and control.
- The early secretory antigenic target 6 kDa protein (ESAT-6) is a well-known Mycobacterium tuberculosis antigen.
Purpose of the Study:
- To investigate human T cell responses to ESAT-6 and its epitopes in TB patients and controls.
- To assess the potential of ESAT-6 as a diagnostic reagent for TB.
Main Methods:
- Human T cell responses were analyzed in TB patients and control subjects from high and low TB endemicity regions.
- Responses to ESAT-6 and eight synthetic overlapping peptides were measured.
- Tuberculin purified protein derivative (PPD) responsiveness was used as a baseline.
Main Results:
- ESAT-6 was recognized by 65% of PPD-responsive TB patients.
- A high frequency (58%) of healthy contacts in a high endemicity region (Ethiopia) recognized ESAT-6.
- ESAT-6 contains multiple epitopes, with distinct recognition patterns observed in Danish and Ethiopian patient groups, potentially linked to HLA types.
Conclusions:
- ESAT-6 is frequently recognized by T cells during early stages of tuberculosis infection.
- ESAT-6 demonstrates significant potential as a component of a future TB-specific diagnostic reagent.
- Understanding epitope-specific responses may inform the development of targeted diagnostic and possibly therapeutic strategies.
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