ELEVATED IL-8 AND MCP-1 IN THE BRONCHOALVEOLAR LAVAGE FLUID OF PATIENTS WITH IDIOPATHIC PULMONARY FIBROSIS AND PULMONARY SARCOIDOSIS

The potential for interleukin-8 (IL-8) and monocyte chemotactic protei n-1 (MCP-1) to induce neutrophil and mononuclear phagocyte accumulatio n in the lungs of patients with pulmonary sarcoidosis and idiopathic p ulmonary fibrosis (IPF) was investigated. Bronchoalveolar lavage (BAL) fluids from 12 patients with IPF and 15 with sarcoidosis were concent rated by reversed-phase chromatography, and their IL-8 and MCP-1 conce ntrations assessed by enzyme-linked immunosorbent assay (ELISA), chemo taxis, and enzyme-releasing assays with monocytes and neutrophils. ELI SA revealed significantly elevated concentrations of MCP-1 (20.1 ng/mg albumin) in the BAL fluids of patients with pulmonary sarcoidosis and those with IPF (41.8 ng/mg) in comparison to 11 normal individuals (4 .24 ng/mg) and 15 patients with chronic bronchitis (CB) (5.16 ng/mg). Similarly the chemotactic activity for monocytes (MCP-1 equivalent) wa s strongly increased in patients with sarcoidosis (86.03 ng/mg) as wel l as in those with IPF(54.47 ng/mg). The chemoattractant activity of n ormal individuals and CB patients was 7- or 3-fold lower, respectively . Patients with IPF and sarcoidosis also had elevated IL-8 levels (15. 5 and 26.0 ng/mg, respectively; normals: 2.14 ng/mg; and CB patients: 4.23 ng/mg) and greater neutrophil chemotaxis (60.25 and 49.68 ng/mg, respectively; normals: 0.35 ng/mg; and CB patients: 11.06 ng/mg). Thes e data suggest that increased levels of both MCP-1. and IL-8 may be ch aracteristic for sarcoidosis or IPF. It appears likely that both of th ese chemoattractants contribute to the influx of monocytes and neutrop hils into the pulmonary alveolus and interstitium in these diseases.