The number of interleukin 1 receptors on lung fibroblasts in patients withidiopathic pulmonary fibrosis

Background: We investigated the expression of the IL-1 receptor on lung fib roblasts in patients with idiopathic pulmonary fibrosis (IPF) the histology of wh ich was diagnosed as usual interstitial pneumonia. Method: I-125-lab eled IL-1 alpha bound to lung fibroblasts in a specific and saturable manne r in lung fibroblasts obtained from both IPF patients and control subjects. Results: Scatchard plot analysis revealed a single type of binding site in both groups. In total, 8,600 +/- 1,450 (mean I-SD) sites/cell with a disso ciation constant (K-d) Of 1.83 +/- 0.28 (mean +/- SD) nMin patients with IP F and 7,920 +/- 1,470 sites/cell with a K-d of 2.43 +/- 0.49 nM in control subjects were counted. Furthermore, affinity cross-linking experiments reve aled that the IL-1 receptor on lung fibroblasts in patients with IPF and co ntrol subjects had a molecular size of 80 kD. Conclusion: In conclusion, ty pe I receptor was present on human lung fibroblasts, but there were no diff erences in number or affinity between IPF patients and controls.