Evaluation of high-mobility group box 1 protein concentration in serum of patients with M. tuberculosis infection

Infection with Mycobacterium tuberculosis is accompanied by an intense inflammatory response. Recently, a new mediator of inflammation, HMGB1 protein has been identified that contributes to acute lung injury. However, its role in the systemic inflammatory response in tuberculosis has not been thoroughly investigated. We investigated the systemic levels of HMGB1 and TNF-α in patients with active and latent lung tuberculosis as a prognostic marker of disease activity. The study was performed to 70 patients with confirmed Mycobacterium tuberculosis infection and other than tuberculosis lung diseases and in 20 healthy persons. Serum HMGB1 and TNF-α concentrations were measured by ELISA. The highest concentration of HMGB1 was detected in the bloodstream of people with Mtb infection (latent and active). Its concentration increased significantly in sera of patients with active tuberculosis (47.5 ng/ml), compared to patients with other lung diseases (36.87 ng/ml). TNF-α had significantly higher concentration in a patients group compared to healthy controls, with the highest concentration in the LTBI group of patients (0.136 ng/ml). We observed a strong positive correlation between TNF-α and HMGB1 concentrations in patients with tuberculosis infections. We conclude that HMGB1 is secreted during active and latent tuberculosis in the highest amounts compared to other lung diseases.