Study on serum Th1/Th2 cytokines levels and associated factors in pulmonary tuberculosis patients

Objective To investigate the serum concentration levels and associated factors of T helper 1 (Th1) (IFN-γ, interleukin (IL)-2), and Th2 (IL-4, IL-10) cytokines in pulmonary TB patients before and after anti-TB treatment.Methods Permanent Shanghai residential pulmonary TB patients diagnosed in 8 designated hospitals from 5 tuberculosis control demonstration districts from May 2013 to August 2015 were enrolled.Questionnaires survey was conducted covering geographic,demographic,social-economic information, clinical manifestation and past medical history. The blood samples were taken before and after 2 months of anti-TB treatment. Enzyme-linked immunosorbent assay (ELISA) was used to assess the level of serum IFN-γ, IL-2, IL-4, and IL-10.Results 309 TB patients were enrolled, among which 80.6% were sputum smear positive (SS+). The male-to-female ratio was 2.64 and the average age was 51.43±18.29 years. The negative conversion rate of sputum smear at the end of 2 months of anti-TB treatment was 72.69%.The serum levels of IFN-γ(45.11 pg/mL to 36.17 pg/mL),IL-2 (15.12 pg/mL to 9.96 pg/mL), and IL-10(28.72 pg/mL to 12.28 pg/mL) were significantly decreased after 2 months of anti-TB treatment. The differences were with statistical significance. The difference of serum IL-4 before and after the treatment was without statistical significance. The cytokines rate of IFN-γ/IL-4 before and after 2 months of anti-TB treatment was 3.59, 2.17, respectively, and the difference was with statistical significance (t=4.715,P<0.01).Conclusion The immune system of pulmonary TB patients was obviously disordered. After 2 months of anti-TB treatment, the level of serum IFN-γ, IL-2, and IL-10 decreased as well as the cytokines rate of IFN-γ/IL-4. Monitoring the serum levels of relative cytokines may be helpful to evaluate the course of pulmonary tuberculosis and the efficacy of the treatment.