Ficolins and Mannose-Binding Lectin in Danish patients with sarcoidosis.

Mannose-Binding Lectin (MBL) is a prognostic marker in pulmonary diseases. Ficolins, sharing many structural and functional similarities with MBL, may also be involved in the pathogenesis of pulmonary diseases. The objectives of the study were to establish whether plasma concentrations of Ficolin-2, -3, and MBL in Danish patients with sarcoidosis and control persons differed and whether they were of prognostic significance. We retrospectively included 46 consecutive patients (26 male, 20 female) and 51 age- and sex-matched healthy control persons (28 male, 23 female). Information about the patients was obtained from their medical records. We measured plasma concentrations of Ficolin-2, -3, and MBL using ELISA. There was a significant difference in the patients' mean Ficolin-3 plasma level (14.9 microg/ml; +/-2SD: 6.7-23.1) compared with the control persons' (21.6 microg/ml; +/-2SD: 12.7-30.5). The difference was 6.7 microg/ml (95% CI: 5.0-8.4 microg/ml; p<0.001). In the patients, Ficolin-3 correlated inversely with the CD4(+)/CD8(+)-ratio (Spearman's Rho=-0.37; p=0.021; n=39). There were no significant differences in plasma concentrations of Ficolin-2 or MBL between the two groups. Ficolin-3 concentrations were lower in plasma from patients with sarcoidosis. This suggests a possible involvement of Ficolin-3 in the complex pathophysiology of sarcoidosis. However, we could not show the applicability of Ficolin plasma level measurement as a marker of disease activity or of prognostic significance in sarcoidosis.