Th1 cytokine pattern (IL-12 and IL-18) in bronchoalveolar lavage fluid (BALF) before and after treatment with interferon gamma-1b (IFN-gamma-1b) or colchicine in patients with idiopathic pulmonary fibrosis (IPF/UIP).Sarcoidosis Vasc Diffuse Lung Dis. 2004 Jun; 21(2):105-10.SV
BACKGROUND AND AIM
Characterization of the biologic effects of Th1 cytokines will enhance the understanding of idiopathic pulmonary fibrosis (IPF) pathogenesis and treatment selection. Th1 response is characterized by increased expression of IFN-gamma, interleukin (IL)-12 and IL-18. The present study aims to evaluate the role of Th1 cytokines and their possible changes in the bronchoalveolar lavage fluid (BALF), before and after treatment with IFN-gamma-1b or colchicine.
PATIENTS AND METHODS
We studied prospectively 10 patients (8 male, 2 female) of median age 67 yr with histologically confirmed IPF/UIP. Patients were randomly assigned to receive either IFN-gamma-1b 200 microg sc (5 patients) or colchicine 1 mg qd (5 patients) plus prednisone 10 mg qd. BALF IL-12 and IL-18 levels were measured before and after treatment.
BALF IL-12 levels before and after treatment did not differ significantly between the two treatment groups. However, BALF IL-18 levels were significantly decreased after treatment with IFN-gamma-1b (mean +/- SD, 58.4 +/- 15.6 pg/mL vs 42.8 +/- 4.90 pg/mL, p < 0.05). A significant difference was also found after treatment with colchicine (mean +/- SD, 66.8 +/- 36.9 pg/mL vs 42.6 +/- 1.08 pg/mL, p < 0.01). A significant correlation was found between IL-18 BALF levels and the BALF neutrophils (r = 0.75, p = 0.024).
Our data suggest the potential role of IL-18 as an inflammatory marker in the pathogenetic pathway of IPF such as its possible downregulation by IFN-gamma-1b treatment. Further studies are needed in a higher number of patients in order to define the precise role of both cytokines during the immunoregulatory response with IFN-gamma-1b.