Interleukin 8 (IL-8) is Produced by the Bronchoalveolar Lavage Cell Population from Patients with Active but not Inactive Sarcoidosis
Pulmonary sarcoidosis results in fibrotic changes within the lungs in some patients but the mechanisms by which this occurs are poorly understood. Interleukin-8 (IL-8) is a potent chemoattractant cytokine which has been proposed as playing a role in the development of lung injury and subsequent fibrosis in other forms of pulmonary disease. We considered that IL-8 might have a similar role in pulmonary sarcoidosis. In order to investigate this, bronchoalveolar lavage was performed on three groups of subjects: 6 symptomatic patients with biopsy proven sarcoidosis prior to any treatment, 6 asymptomatic patients with biopsy proven sarcoidosis and no treatment for at least 6 months, and 6 normal volunteers. Whole cell populations from this lavage were cultured for 24 hours in serum free media. The resultant supernatants were assayed for the presence of IL-8 using a highly specific double ELISA. No IL-8 was detected in the cell culture supernatants of the normal volunteers nor the asymptomatic patients with sarcoidosis, but was present (11.93 ± 0.71 ng/ml, SD ± SEM) in the supernatants from those with active sarcoidosis. These findings suggest that IL-8 production may have a role in the acute inflammatory phase of sarcoidosis, although the mechanisms by which subsequent fibrosis develops remain unclear.