Mycobacterium tuberculosis in a Trap: The Role of Neutrophil Extracellular Traps in Tuberculosis.

Mycobacterium tuberculosis complex causes tuberculosis (TB), a disease that causes pulmonary inflammation but can also affect other tissues. Despite macrophages having a defined role in TB immunopathogenesis, other innate immune cells, such as neutrophils, are involved in this process. These cells have high phagocytic ability and a microbial-killing machine comprised of enzymes, antimicrobial peptides, and reactive oxygen species. In the last two decades, a new neutrophil immune response, the neutrophil extracellular traps (NETs), has been intensely researched. NETs comprise DNA associated with histones, enzymes, and antimicrobial peptides. These structures are related to antimicrobial immune response and some immuno-pathogenesis mechanisms. This mini review highlights the role of NETs in tuberculosis and how they can be helpful as a diagnostic tool and/or therapeutic target.

In vitro and in silico evaluation of the anti-leishmania activity of synthetic chalcones.

Leishmaniasis is a group of neglected, vector-borne infectious diseases that affect millions of people around the world. The medications available for its treatment, especially in cases of visceral leishmaniasis, are old, outdated and have serious side effects. In this work, 10 chalcones were synthesised and evaluated in vitro against promastigotes and axenic amastigotes of Leishmania infantum. Compounds CP04 and CP06 were the most promising, respectively presenting IC50 values = 13.64 ± 0.25 and 11.19 ± 0.22 µM against promastigotes, and IC50 = 18.92 ± 0.05 and 22.42 ± 0.05 µM against axenic amastigotes. Only compound CP04 did not show cytotoxicity against peripheral blood mononuclear cells (PBMCs). Molecular docking studies conducted with sterol 14-alpha demethylase (CYP-51) (PDB: 3L4D) and trypanothione reductase (PDB: 5EBK) enzymes from L. infantum evidenced the great affinity of compound CP04 for these targets, presenting Moldock score values of -94.0758 and -50.5692 KJ/mol-1.

Leishmaniasis: Immune Cells Crosstalk in Macrophage Polarization.

Leishmaniasis is a complex infectious parasitic disease caused by protozoa of the genus Leishmania, belonging to a group of neglected tropical diseases. It establishes significant global health challenges, particularly in socio-economically disadvantaged regions. Macrophages, as innate immune cells, play a crucial role in initiating the inflammatory response against the pathogens responsible for this disease. Macrophage polarization, the process of differentiating macrophages into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes, is essential for the immune response in leishmaniasis. The M1 phenotype is associated with resistance to Leishmania infection, while the M2 phenotype is predominant in susceptible environments. Notably, various immune cells, including T cells, play a significant role in modulating macrophage polarization by releasing cytokines that influence macrophage maturation and function. Furthermore, other immune cells can also impact macrophage polarization in a T-cell-independent manner. Therefore, this review comprehensively examines macrophage polarization's role in leishmaniasis and other immune cells' potential involvement in this intricate process.