[Show abstract][Hide abstract] ABSTRACT: Sarcoidosis is a systemic granulomatous disorder of unknown aetiology involving multiple organs and often associated with non-granulomatous microangiopathic lesions in various organs. Increased angiogenesis-inducing ability of activated alveolar macrophages was found in bronchoalveolar specimens from patients with pulmonary sarcoidosis and from patients with extrapulmonary involvement. In contrast, decreased levels of vascular endothelial growth factor (VEGF) were found in BAL fluid recovered from sarcoid-associated pulmonary fibrosis. This study evaluated whether sarcoidosis is associated with abnormalities of VEGF and IL-8 in induced sputum (IS) samples.
Twenty-three sarcoid patients and 13 controls performed IS. CD4/CD8 T-cell subsets were measured, as were pulmonary function tests and VEGF and IL-8.
Sarcoid patients showed significantly higher mean %lymphocytes (P = 0.04), significantly higher mean CD4/CD8 ratio (P = 0.0001) and significantly lower VEGF levels (P = 0.03) than controls. Patients with stages III-IV sarcoidosis showed a lower level of VEGF compared with those with stages I-II sarcoidosis (P = 0.048). IL-8 was detected in 10/35 samples and positively correlated with % neutrophils (P = 0.054) and eosinophils (P = 0.045). VEGF immunohistochemical staining showed a mixed pattern of expression in the same tissue samples and was low in fibrotic tissue areas.
VEGF in IS samples may reflect impairment in angiogenesis associated with the extent of sarcoid fibrosis and functional disorders.