Mycobacterium tuberculosis multidrug resistant strain M induces an altered activation of cytotoxic CD8+ T cells.
In human tuberculosis (TB), CD8+ T cells contribute to host defense by the release of Th1 cytokines and the direct killing of Mycobacterium tuberculosis (Mtb)-infected macrophages via granule exocytosis pathway or the engagement of receptors on target cells. Previously we demonstrated that strain M, the most prevalent multidrug-resistant (MDR) Mtb strain in Argentine, is a weak inducer of IFN-γ and elicits a remarkably low CD8-dependent cytotoxic T cell activity (CTL). In contrast, the closely related strain 410, which caused a unique case of MDR-TB, elicits a CTL response similar to H37Rv. In this work we extend our previous study investigating some parameters that can account for this discrepancy. We evaluated the expressions of the lytic molecules perforin, granzyme B and granulysin and the chemokine CCL5 in CD8+ T cells as well as activation markers CD69 and CD25 and IL-2 expression in CD4+ and CD8+ T cells stimulated with strains H37Rv, M and 410. Our results demonstrate that M-stimulated CD8+ T cells from purified protein derivative positive healthy donors show low intracellular expression of perforin, granzyme B, granulysin and CCL5 together with an impaired ability to form conjugates with autologous M-pulsed macrophages. Besides, M induces low CD69 and IL-2 expression in CD4+ and CD8+ T cells, being CD69 and IL-2 expression closely associated. Furthermore, IL-2 addition enhanced perforin and granulysin expression as well as the degranulation marker CD107 in M-stimulated CD8+ T cells, making no differences with cells stimulated with strains H37Rv or 410. Thus, our results highlight the role of IL-2 in M-induced CTL activity that drives the proper activation of CD8+ T cells as well as CD4+ T cells collaboration.
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Laura
L
Geffner
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Juan Ignacio
JI
Basile
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Noemí
N
Yokobori
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Denise
D
Kviatcovsky
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Carmen
C
Sabio y García
Laboratorio de Micobacterias, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
Viviana
V
Ritacco
Laboratorio de Micobacterias, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
Beatriz
B
López
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
María del Carmen
Mdel C
Sasiain
Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
Silvia
S
de la Barrera
D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D018946:Chemokine CCL5 / Q000235:genetics / Q000378:metabolism; D003602:Cytotoxicity, Immunologic; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D053804:Granzymes / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000235:genetics / Q000378:metabolism; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics / Q000276:immunology*; D054353:Perforin / Q000235:genetics / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism; D000099192:CD69 Antigens
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018946:Chemokine CCL5; D053804:Granzymes; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D037181:Lectins, C-Type; D054353:Perforin; D000099192:CD69 Antigens; C075005:GNLY protein, human