Foxp3+CD25(high) CD4+ regulatory T cells from indeterminate patients with Chagas disease can suppress the effector cells and cytokines and reveal altered correlations with disease severity.
Immunoregulatory mechanisms are important to control the intense immune activity induced in Chagas disease. We evaluated the phenotypic profile and the mechanisms by which Treg cells function in patients with the indeterminate (IND) and cardiac (CARD) clinical forms of Chagas disease. The frequency of Foxp3(+)CD25(high) CD4(+)-T cells is augmented and correlated with the maintenance of a better cardiac function in IND. Treg cells from IND present suppressive activity, although the mechanism is not IL-10 or CTLA-4 dependent and are able to produce augmented levels of IL-17, IL-10 and granzyme B being its frequency correlated with percentage of Annexin V(+) CD4(+)-cells. In contrast, CARD presents higher frequency of IL-6(+), IFN-gamma(+), TNF-alpha(+) and CTLA-4(+) Treg-cells than IND. Thus, our data suggest that Treg cells have an important role in controlling the exacerbated immune response and morbidity in Trypanosoma cruzi infection, probably modulating the cytokine environment and/or killing effector cells.
Laboratório de Imunologia Celular e Molecular, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brazil.
F F
FF
de Araújo
R
R
Corrêa-Oliveira
M O C
MO
Rocha
A T
AT
Chaves
J A
JA
Fiuza
R C G
RC
Fares
K S
KS
Ferreira
M C P
MC
Nunes
T S
TS
Keesen
M P S
MP
Damasio
A
A
Teixeira-Carvalho
J A S
JA
Gomes
D000328:Adult; D000368:Aged; D060908:CTLA-4 Antigen / Q000276:immunology / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D014355:Chagas Disease / Q000276:immunology* / Q000378:metabolism / Q000469:parasitology; D016207:Cytokines / Q000276:immunology* / Q000378:metabolism; D004452:Echocardiography; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000276:immunology* / Q000378:metabolism; D006334:Heart Function Tests; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D016753:Interleukin-10 / Q000276:immunology / Q000378:metabolism; D020381:Interleukin-17 / Q000276:immunology / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology* / Q000378:metabolism; D015850:Interleukin-6 / Q000276:immunology / Q000378:metabolism; D018655:Lymphocyte Count; D008875:Middle Aged; D012720:Severity of Illness Index; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D014349:Trypanosoma cruzi / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism
D060908:CTLA-4 Antigen; D016207:Cytokines; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508017:IL2RA protein, human; D020381:Interleukin-17; D053645:Interleukin-2 Receptor alpha Subunit; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007371:Interferon-gamma