Assessment of Serum IL-1, IL-2 and IFN-γ Levels in Untreated Pulmonary Tuberculosis Patients: Role in Pathogenesis

Background and Aims Tuberculosis (Tb) infection is controlled by cell-mediated immunity through mediation of IL-1, IL-2 and IFN-γ. In this study IL-1, IL-2 and IFN-γ were determined in serum samples of untreated pulmonary Tb and control group including apparently healthy individuals or contacts and normal healthy blood donors with an objective of understanding defect(s), if any, in synthesis of any of these cytokines that may lead to a diseased state of Tb. Methods IL-1, IL-2 and IFN-γ were measured in serum samples of untreated Tb patients ( n = 33), contacts ( n = 19) and healthy individuals ( n = 20) by commercially available monoclonal antibody-based ELISA. Results Statistically significant differences in IL-1 and IFN-γ concentrations between groups of pulmonary Tb and controls were observed, whereas no significant difference in IL-2 was seen. Conclusions In the present study, increased levels of cytokines in patients with pulmonary Tb are indicative of Th1 response. An increased level of cytokine (IFN-γ) in patients with untreated pulmonary Tb appears to be functionally defective.