DETERMINATION OF THE FREQUENCY OF MYELOID-DERIVED SUPPRESSOR CELLS DURING HUMAN ACTIVE TUBERCULOSIS

FLORENCIA CASTELLO; MARÍA PAULA MORELLI; JOAQUIN M. PELLEGRINI; AMIANO, NICOLÁS; GARCÍA, VERÓNICA; NANCY TATEOSIAN

Congreso; LXIII Reunión Científica Anual de la Sociedad Argentina de Investigaciones Clinicas (SAIC), LXVI Reunión Anual de la Sociedad Argentina de Inmunología (SAI); 2018

Tuberculosis (TB), together with HIV infection, is the leading causeof death from an infectious disease worldwide. In fact, Mycobacteriumtuberculosis (Mtb) causes almost 10 million of new cases peryear. Myeloid-derived suppressor cells (MDSCs) display an immunosuppressivefunction during several pathological conditions suchas cancer and hepatitis. MDSC-mediated suppression of host immunityduring chronic inflammation is crucial for immune regulation andtolerance to limit immunopathology. Furthermore, the unfavorableeffects of MDSCs are evident in tumor biology where they accumulateand suppress cytokines Th1 responses. The aim of this workwas to study the expression of MDSCs during active TB. Thus, weinvestigated the frequency of granulocytic MDSCs (g-MDSCs) andmonocytic MDSCs (m-MDSCs) in peripheral blood mononuclearcells (PBMCs) from TB patients classified as high (HR-TB) or low(LR-TB) responders on the basis of their immunological response toMtb-antigen. Using flow cytometry, we observed that both g-MDSCs(CD14- CD11b+ CD15+) and m-MDSCs (CD14+ CD11b+ HLA-DR-/low)showed significantly higher levels (P