Changes in serum cytokine levels in active tuberculosis with treatment

Abstract

It has been reported that IFN-gamma, TNF-alpha, and IL-12 stimulate, and that IL-10, TGF-beta, and IL-4 suppress the protective immune response against tuberculosis. We aim to evaluate changes in the serum levels of pro and antiinflammatory cytokines in active pulmonary tuberculosis (APTB) and the possible effects of treatment on these changes. Serum IL-12p40, IL-4, IL-10, TNF-alpha, IFN-gamma, and TGF-beta1 levels were determined in 20 APTB cases (group 1) before and 2, 4, and 6 months after therapy. The same parameters were also determined in 9 inactive pulmonary tuberculosis (IPTB) cases (group 2) and 9 healthy controls (HC, group 3). Before treatment, the mean serum IFN-gamma, TNF-alpha, and IL-10 levels in group 1 were statistically higher than those in group 2 (P=.001, P=.024, P=.016, resp) or group 3 (P=.003, P=.002, P=.011, resp). The levels in group 1 decreased significantly after treatment (P=.001 for IFN-gamma, P=.004 for TNF-alpha, P=.000 for IL-10). The serum levels of IL-12p40 were significantly higher in group 1 than in group 3 (P=.012) and decreased insignificantly after treatment. There was no difference in serum IL-4 and TGF-beta1 levels among the groups (P>.05). Because the serum IL-12p40, IL-10, TNF-alpha, and IFN-gamma levels were high in APTB, we believe that these cytokines have important roles in the immune response to Mycobacterium tuberculosis (M tuberculosis). These parameters could be used in follow-up as indicators of the success of APTB therapy.

Figure 1

The mean serum levels of (a) IL-12 and TNF-α and (b) IL-10 and IFN-γ in APTB patients (n = 20). Naïve: patients who had not received ATT. 2T: patients who received ATT for two months. 4T: patients who received ATT for four months. 6T: patients who received ATT for six months. ^aSignificantly different compared with 4T (P = .034 for TNF-α, P = .018 for IL-10) and 6T (P = .004 for TNF-α, P = .000 for IL-10) patients. ^bSignificantly different compared with 2T (P = .008), 4T (P = .000), and 6T (P = .001).

Figure 1

The mean serum levels of (a) IL-12 and TNF-α and (b) IL-10 and IFN-γ in APTB patients (n = 20). Naïve: patients who had not received ATT. 2T: patients who received ATT for two months. 4T: patients who received ATT for four months. 6T: patients who received ATT for six months. ^aSignificantly different compared with 4T (P = .034 for TNF-α, P = .018 for IL-10) and 6T (P = .004 for TNF-α, P = .000 for IL-10) patients. ^bSignificantly different compared with 2T (P = .008), 4T (P = .000), and 6T (P = .001).