Gamma delta T cell responses associated with the development of tuberculosis in health care workers.
Ordway, Diane J;
Pinto, Luisa;
Costa, Leonor;
Martins, Marta;
Leandro, Clara;
Viveiros, Miguel;
Amaral, Leonard;
Arroz, Maria J;
Ventura, Fernando A;
Dockrell, Hazel M;
(2005)
Gamma delta T cell responses associated with the development of tuberculosis in health care workers.
FEMS immunology and medical microbiology, 43 (3).
pp. 339-350.
ISSN 0928-8244
DOI: https://doi.org/10.1016/j.femsim.2004.09.005
Permanent Identifier
Use this Digital Object Identifier when citing or linking to this resource.
This study evaluated T cell immune responses to purified protein derivative (PPD) and Mycobacterium tuberculosis (Mtb) in health care workers who remained free of active tuberculosis (HCWs w/o TB), health care workers who went on to develop active TB (HCWs w/TB), non-health care workers who were TB free (Non-HCWs) and tuberculosis patients presenting with minimal (Min TB) or advanced (Adv TB) disease. Peripheral blood mononuclear cells (PBMC) were stimulated with Mtb and PPD and the expression of T cell activation markers CD25+ and HLA-DR+, intracellular IL-4 and IFN-gamma production and cytotoxic responses were evaluated. PBMC from HCWs who developed TB showed decreased percentages of cells expressing CD8+CD25+ in comparison to HCWs who remained healthy. HCWs who developed TB showed increased gammadelta TCR+ cell cytotoxicity and decreased CD3+gammadelta TCR- cell cytotoxicity in comparison to HCWs who remained healthy. PBMC from TB patients with advanced disease showed decreased percentages of CD25+CD4+ and CD25+CD8+ T cells that were associated with increased IL-4 production in CD8+ and gammadelta TCR+ phenotypes, in comparison with TB patients presenting minimal disease. TB patients with advanced disease showed increased gammadelta TCR+ cytotoxicity and reduced CD3+gammadelta TCR- cell cytotoxicity. Our results suggest that HCWs who developed TB show an early compensatory mechanism involving an increase in lytic responses of gammadelta TCR+ cells which did not prevent TB.