CORRELATION OF GM-CSF MESSENGER-RNA IN BRONCHOALVEOLAR FLUID WITH INDEXES OF CLINICAL ACTIVITY IN SARCOIDOSIS

Background-Granulocyte-macrophage colony stimulating factor (GM-CSF) h as several proinflammatory effects, some of which potentially favour g ranuloma formation. Its mRNA expression by the inflammatory cells reco vered from lungs of patients with pulmonary sarcoidosis has been previ ously reported. In this study an association between GM-CSF expression and manifestations of the disease was explored. Methods-GM-CSF mRNA w as detected by reverse transcription polymerase chain reaction in the cells of bronchoalveolar lavage (BAL) fluid of 20 patients with pulmon ary sarcoidosis. Results-GM-CSF mRNA expression was positive in 15 of 20 patients with sarcoidosis. Fourteen of the IS patients with positiv e mRNA expression had worsening or unchanged disease during the year p receding this study, on the basis of radiographic or physical findings , or both, whereas all five ''negative'' patients were judged to be im proving. Similarly, serum levels of angiotensin converting enzyme, the proportion of lymphocytes in BAL fluid, and the CD4+/CD8+ ratio of ly mphocytes in BAL fluid were significantly higher in the positive patie nts. Conclusions-There was an association between the presence of GM-C SF mRNA in the cells in BAL fluid and other indices of disease activit y in sarcoidosis.