Perturbation of the Myeloid Compartment in Human Tuberculosis

PELLEGRINI, J; CIALLELLA, L; GARCIA, VE; AMIANO, N; MARTIN CANDELA; LEVI, ALBERTO; TATEOSIAN, NANCY LILIANA; MORELLI, MARÍA P.; MARTINENA CAMILA; PALMERO, DJ

Simposio; Keystone eSymposia; 2020

Alterations of myeloid cells populations have been reported in patients with tuberculosis (TB), but little is known about how it is affected by its immunological status. Circulating monocytes can be divided into classical (CD14+CD16-) and non-classical monocytes (CD14+CD16+), and the classical monocytes also contain monocytic myeloid-derived suppressor cells (M-MDSC). The aim of the study was to evaluate the occurrence of the monocyte subpopulations in human tuberculosis. Blood mononuclear cells from TB patients at various times of anti-TB treatment, and healthy donor subjects (HD), were double-stained for monocyte (CD14 CD16) and for MDSC (CD14 CD11b HLA-DR CD15), then analyzed by flow cytometry. TB subjects were classified as High (HR) and Low (LR) Responder according to their T cell responses against the antigen, and cytokine expression upon Mtb stimulation.We observe that TB patients present higher percentage of non-classical monocytes but this increase is evident only TB LR population. Moreover, MDSC cells are increase in TB patients compare to HD, and the frequency of M-MDSC correlated with IFN-γ release after Mtb-antigen stimulation. TB LR individuals are those with the highest % of M-MDSC but, on the other hand, the increase in G-MDSC percentage is evident in TB HR compare to TB LR and HD. Normal percentages of CD14+CD16+cells and M-MDSC were restore after first 14 days of anti-TB treatment. Conclusion: Immunological status of TB patients determinates de the frequency and profile of monocytes and MDSC. The recovery after 14 days of a normal % of these cells population indicating that monocyte and MDSCs frequency were relative to the pathogenesis of Mtb infection.