LIPOCORTIN-I GENE-EXPRESSION IS HIGHER IN BLOOD MONOCYTES THAN IN BALFLUID MACROPHAGES IN PATIENTS WITH PULMONARY SARCOIDOSIS

Background nod aim of work: Lipocortin I, induced by corticosteroids i n vivo is considered to be related to cell activation and differentiat ion in mononuclear phagocytes, key cells in the process of epithelioid cell granuloma formation in sarcoidosis. Therefore, we focused on the expression of lipocortin I gene in mononuclear phagocytes in patients with sarcoidosis. Method: The amounts of transcripts of lipocortin I gene obtained from both BAL fluid macrophages and blood monocytes were measured by RT-PCR and HPLC, and then standardized as the ratio of li pocortin I/beta-actin for comparison. Results: 1. Smoking did not affe ct the expression of lipocortin I gene in BAL fluid macrophages and mo nocytes. 2, There were no differences in the amounts of expression in BAL fluid macrophages between patient groups (nonsmokers and smokers), or between patients and healthy subjects. 3. The gene expression in B AL fluid macrophages was higher than that in monocytes in patients wit h IPF (macrophages 1.23 +/- 0.48, vs monocytes 0.50 +/- 0.38, p<0.05) and healthy subjects (nonsmoker: 1.66 +/- 1.17, vs 0.34 +/- 0.26, p<0. 05, smoker: 1.98 +/- 0.96, vs 0.34 +/- 0.38, p<0.05, but sarcoidosis p atients showed a higher expression of lipocortin I gene even in monocy tes (2.62 +/- 1.87, vs 2.66 +/- 2.21). Conclusion: The increase in lip ocortin I gene expression in monocytes was a disease-related finding i n sarcoidosis.