AVALIAÇÃO DAS SUBPOPULAÇÕES DE MONÓCITOS EM PACIENTES COM TUBERCULOSE PULMONAR

Macrophages are important components of the innate immune response against Mycobacterium tuberculosis (Mtb) and may play an important role in the pathogenesis of tuberculosis (TB). Macrophages are derived from monocytes, which are classified into subpopulations from the expression of CD14 and CD16 surface molecule. They are denominated classics, intermediate and non-classical, and have functional and phenotypic differences. The factors that lead to the development of active tuberculosis are not clear yet. However, an imbalance between subpopulations of monocytes may be involved in the immunopathogenesis of TB, since macrophages are important cells in the initial immune responses of the disease. In this study we evaluated the monocyte subsets in patients with active and latent TB (ILTB). Volunteers with active TB, ILTB and healthy subjects were recruited to evaluate the frequency, levels of activation and cytokine production of blood monocytes subsets circulating and after the antigenic stimulation by flow cytometry. Our results did not show significant differences in the frequency, activation levels and cytokine production of monocytes subsets between studies groups. However, patients with active TB have an increased of frequency and activated levels of classical monocytes after antigenic stimulation compared to healthy controls. An expansion of CD16+ in monocytes subsets of TB patient was not observed. Moreover, it was observed an expansion and increased activation of CD16- monocytes after antigenic stimulation in individuals TB and LTB. Thus, the classical monocytes seems to play a role in TB infection, since this subpopulation expands and appears more active primarily after antigenic stimulation in response to Mce1A. However, this expansion of classical monocytes in TB still needs to be evaluated.