CTSG and tuberculosis: In TB, neutrophils are fundamental mediators of the innate immune response, as they provide protection trying to kill mycobacteria through the release of their granules, notably, the primary (azurophilic) granules, which contain myeloperoxidase (MPO), cathepsin G, elastase, proteinase 3, and defensin, responsible for pathogen clearance (53, 54).