cathepsin-g and Tuberculosis

Neutrophil serine proteases, such as cathepsin G (CG) and neutrophil elastase (NE), have been implicated in the protective response against infections, including experimental mycobacterial infections. The goal of this study was to explore the role of CG in immunocompetent mice challenged aerogenically with Mycobacterium tuberculosis. We used genetically CG- or CG/NE-deficient mice to define the importance of these neutrophil serine proteases for antibacterial protection, granulomatous response, and survival. In addition, we explored the effect of intratracheally delivered liposomally encapsulated CG/NE as a therapeutic approach early during M. tuberculosis infection. Our data show that the presence of CG or CG/NE prolongs survival in M. tuberculosis-infected mice. However, CG is not directly involved in antibacterial defenses, and exogenous intratracheal administration of CG combined with NE does not reduce bacterial loads in the lungs of M. tuberculosis-infected mice.

Topics: Animals; Anti-Bacterial Agents; Cathepsin G; Immunotherapy; Leukocyte Elastase; Mice; Mice, Inbred C57BL; Mice, Knockout; Mycobacterium tuberculosis; Neutrophils; Tuberculosis

To investigate the changes in serum protease and cytokine in patients with silicosis, tuberculosis, and lung cancer.. Serum samples of patients with silicosis, tuberculosis, and lung cancer were collected. The variation trends of the expression of granzyme A, cathepsin G, apolipoprotein A, and interferon-β (IFN-β) were analyzed using enzyme-linked immunosorbent assay.. The concentration of apolipoprotein A of the silicosis group was 200 µg/ml, significantly higher than those of the tuberculosis and lung cancer groups (P < 0.05), and the lung cancer group had a significantly higher concentration of apolipoprotein A compared with the tuberculosis group (P < 0.05). The silicosis group had significantly higher expression of cathepsin G compared with the tuberculosis and lung cancer groups (P < 0.05), and the tuberculosis group and lung cancer group showed no significant difference in the concentration of cathepsin G (P > 0.05). The tuberculosis group had a significantly higher concentration of granzyme A than the silicosis and lung cancer groups (P < 0.05), and the silicosis group and lung cancer group had similar protein concentration trends (P > 0.05). The tuberculosis group and lung cancer group had significantly higher concentration of IFN-β compared with the silicosis group (P < 0.05), and the tuberculosis group and lung cancer group showed no significant difference in IFN-β concentration (P > 0.05).. This study may offer diagnostic markers for the clinical diagnosis of silicosis, tuberculosis, and lung cancer, and could provide a basis for the research, as well as potential molecular targets for the diagnosis and treatment of these diseases.

Topics: Biomarkers; Cathepsin G; Cytokines; Endopeptidases; Enzyme-Linked Immunosorbent Assay; Granzymes; Humans; Interferon-beta; Lung Neoplasms; Silicosis; Tuberculosis