Imunofenotipagem e perfil de citocinas de linfócitos (CD4+ CD8+) e de pacientes com apresentações radiológicas não avançadas e avançadas da tuberculose pulmonar

Abstract

Despite of being a treatable disease, tuberculosis remains a major public health problem in various regions of the world. Cellular immunity is very important to defend the body against infection caused by Mycobacterium tuberculosis, mainly macrophages, natural killer cells, lymphocyte T CD4+ and CD8+. Nowadays the double-negative áâ e ãä lymphocytes have been evaluated for their role in the defense against intracellular pathogens. The aim of the present study was to investigate whether patients with non-advanced and advanced radiological presentations of pulmonary tuberculosis have any changes regarding the parameters of cellular immunity and on the pattern of cytokines produced by double negative ãä and áâ lymphocytes. A total of 20 patients with pulmonary tuberculosis were evaluated and they were classified as non-advanced radiological presentation (10 patients), advanced radiological presentation (10 patients) and 10 controls without tuberculosis. It was used two approaches in this study: the evaluation of ex-vivo and after in vitro culture. For the ex-vivo study, the markers CD4, CD8, áâ, , CD28, CD69 and HLA-DR were analyzed by flow cytometry in peripheral blood lymphocytes. For the IFN-, TNF-á and IL-10 cytokines determination, it was used the culture supernatant of mononuclear cells from peripheral blood stimulated with antigens of Mycobacterium tuberculosis. Statistical analysis of results showed a lower expression of double-negative ãä lymphocytes and increased expression ofdouble-negative áâ lymphocytes in patients with advanced radiological presentation of tuberculosis when compared to patients with non-advanced radiological presentation. The expression of co-stimulatory molecule CD28 and activation markers CD69 and HLA-DR is increased in double-negative ãä cells of patients with non-advanced radiological presentation which shows a profile of prior activation of these cells in this radiographic appearance of the disease. In relation to the cytokinesproduced after antigen stimulation of leukocytes, it was observed that both cells produce higher levels of inflammatory cytokines IFN-ã and TNF-á in tuberculosis with non-advanced radiological presentation while producing higher levels of immunoregulatory cytokine IL-10 in advanced radiological presentation. Furthermore, the results show that the double negative ãä lymphocytes are better producers of IFN-ã while the double negative áâ lymphocytes are better producers of IL-10. Theseresults showed that the double negative lymphocytes are activated in thebloodstream of patients with tuberculosis and that the evaluation of the expression of CD28, CD69, HLA-DR and the percentage of double negative ãä lymphocytes was able to differentiate both radiological presentations studied. Moreover, both cells exhibited a profile of inflammatory cytokines in non-advanced radiological presentation and immunoregulatory profile in advanced radiological presentation,which also allowed the differentiation between the two groups studied. This study innovatively analyzed the participation of the double negative lymphocytes in different radiological presentations of pulmonary tuberculosis and suggests the possibility of using these markers in monitoring the clinical course of patients. However, furtherstudies are needed involving a larger number of patients evaluated throughout pharmacological treatment.