Immunodiagnosis potential of M. tuberculosis CFP-10 for active tuberculosis / Anáilise do potencial diagnóstico do anígeno CFP-10 expresso pelo M. tuberculosis.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2010

RESUMO

The use of specific antigens of M. tuberculosis is extremely important for early diagnosis of tuberculosis and to control the spread of mycobacteria in the population. The CFP-10 is an antigen that is present in M. tuberculosis, but is absent in M. bovis of BCG and environmental mycobacteria. So, the objective of this study was to determine whether the immune response to recombinant CFP-10 of the M. tuberculosis is able to differentiate the immunity developed by the BCG vaccine that due to infection by mycobacteria. For this, we analyzed the cellular immune response of 18 patients with active TB, 16 treated patients and 19 healthy PPD-positive. The cellular immune response was analyzed by culture of PBMC for assays of cell proliferation and production of Th1 cytokines (IFN-γ and TNF-α), Th2 (IL-4, IL-13) and the regulatory cytokine IL-10 to PHA, BCG and CFP-10. It was possible to observe a significant increase in proliferative response of cells after culture with PHA among treated and healthy participants compared to active patients. Comparison of the proliferation index among the three groups to the BCG and CFP-10 antigen was not statistically significant. In relation to plasma levels of cytokines, IFN-γ was significantly higher in patients with active TB compared to treated patients and healthy subjects. Plasma levels of IL-13 were significantly higher among patients with active TB compared to healthy subjects. Plasma levels of IL-10 were significantly higher among patients with active disease compared to treated patients. In relation to TNF-α and IL-4, no differences were found in plasma levels among the three groups. For the production of cytokines in culture supernatants, there was a significantly higher production of IFN-γ to BCG among healthy individuals when compared to active and treated patients. The production of IL-4 was significantly higher among patients with active TB compared to healthy subjects in the supernatants of cultures without stimulation and after stimulation with BCG and CFP-10. The production of IL-4 after stimulation of PHA was significantly higher in patients with active and treated TB when compared to healthy subjects. The production of IL-13 was significantly higher in treated and active patients compared with healthy individuals after stimulation with PHA. For the production of IL-10, it was significantly higher in the healthy subjects and patients treated when compared to patients with active TB in cultures without stimulation and after stimulation with PHA. With the CFP-10 antigen, there was a greater production of IL-10 among healthy subjects and the difference was significant only for active patients. There was no statistically significant difference in production of TNF-α with the stimuli among the three groups of participants. So among the active patients there was a significant bias Th2, rather than a protective Th1 response. It was not possible to observe a big potential of CFP-10 in inducing IFN-γ production in patients with active tuberculosis. Otherwise, Th2 cytokines (IL-4 and IL-13) were potentially more promising for differentiating sick patients from those healthy or treated. The datas, specially the balance IL-10/IFN-show the existence of a complex model of immunoregulation in patients with tuberculosis.

ASSUNTO(S)

citocinas proliferação celular medicina tuberculosis cfp-10 cytokines cell proliferation tuberculose cfp-10

ACESSO AO ARTIGO

Documentos Relacionados