STUDY ON CYTOKINE PRODUCTION OF PATIENTS WITH PULMONARY TUBERCULOSIS : 2. INVESTIGATION ON PRODUCTION OF CYTOKINES BY PERIPHERAL MONONUCLEAR CELLS FROM PATIENTS WITH PULMONARY TUBERCULOSIS

Interferon-γ (IFN-γ) and interleukin-10 (IL-10)-producing ability of peripheral blood mononuclear cells (PBMC) obtained from patients with active pulmonary tuberculosis (N=17) and healthy controls (N=14) were assessed upon stimulation with purified protein derivatives (PPD). Blood was extracted on two occasions from each patient with active pulmonary tubercu- losis without any underlying diseases ; before the initiation of anti-tuberculous chemother- apy and 2 months later from the negative conversion of Mycobacterium tuberculosis in sputum culture. Adherent cells and non-adherent cells were prepared from PBMC. IFN-γ and IL-10 level were measured by ELISA in culture supernatants of adherent cells and non-adherent cells stimulated with PPD. Non-adherent cells obtained on admission produced IFN-γ significantly higher than did the cells of healthy controls (P＜0.001). Elevated production of IFN-γ by non-adherent cells obtained on admission was reduced after anti-tuberculous treatment (P＜0.03). IL-10 production by non-adherent cells of the patients was lower than that by the cells of healthy controls, although the difference was not statistically significant. IL-10 production by non-adherent cells obtained on admission was significantly correlat- ed with the duration of culture positive in the sputum (P＜0.05). IL-10 level produced by adherent cells from nutritionally normal patients was significant- ly higher than that of healthy controls(P＜0.05), and elevated IL-10 level was significantly reduced aft er therapy (P＜0.05). In the normonourished patients, the duration of culture positive in the sputum of patients with higher level of IL-10 of non-adherent cells (N=5) was significantly longer than that of patients with reduced IL-10 levels after therapy. These results suggests that IL-10 produced by monocytes may diminish the TH 1 responses of patients with pulmonary tuberculosis