Enhanced Expression of Myeloid-Related Protein Complex (MRP8/14) in Macrophages and Multinucleated Giant Cells in Granulomas of Patients With Active Cardiac Sarcoidosis

• Published in: Circulation Journal Vol. 71; no. 10; pp. 1545 - 1550
• Main Authors: Terasaki, Fumio, Fujita, Masatoshi, Shimomura, Hiroaki, Tsukada, Bin, Otsuka, Koji, Otsuka, Kaoru, Katashima, Takashi, Ikemoto, Masaki, Kitaura, Yasushi
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Circulation Society 2007
• Subjects: Adult; Aged; Calgranulin A - metabolism; Calgranulin B - metabolism; Cardiomyopathy; Cardiomyopathy, Dilated - metabolism; Cardiomyopathy, Dilated - pathology; Case-Control Studies; Female; Giant Cells - metabolism; Giant Cells - pathology; Granuloma, Giant Cell - metabolism; Granuloma, Giant Cell - pathology; Humans; Inflammation; Macrophages - metabolism; Macrophages - pathology; Male; Middle Aged; Myeloid-related protein; Myocardium - metabolism; Myocardium - pathology; Pathology; Sarcoidosis; Sarcoidosis - metabolism; Sarcoidosis - pathology
• ISSN: 1346-9843; 1347-4820
• DOI: 10.1253/circj.71.1545

Background The myeloid-related protein complex (MRP8/14) is expressed in activated human macrophages and reported to be involved in the inflammatory process. The expression of MRP8/14 in patients with cardiac sarcoidosis and idiopathic dilated cardiomyopathy (DCM) was investigated. Methods and Results Serum MRP8/14 levels were measured in 35 patients with sarcoidosis and 23 patients with DCM. Sera from 30 normal volunteers served as controls. Additionally, the expression profiles of MRP8/14 in the myocardium from 12 patients with active cardiac sarcoidosis and 10 DCM patients were examined immunohistochemically. Serum MRP8/14 levels were significantly higher in patients with sarcoidosis than in normal controls [515±549 (SD) ng/ml vs 230±115 ng/ml, p=0.0019]. In the sarcoidosis group, serum MRP8/14 levels in patients with definite cardiac involvement (n=10) were significantly higher than in those without (n=25) (974±878 ng/ml vs 332±204 ng/ml, p=0.0227) and they were also higher than in DCM patients (vs 252±108 ng/ml, p=0.0026). Immunohistochemically, MRP8/14 was specifically positive in the cytoplasm of macrophages and multinucleated giant cells in the myocardial granulomas. Conclusions MRP8/14 may be involved in the pathogenesis of sarcoid granulomas. The measurement of serum MRP8/14 levels is useful for the diagnosis of sarcoidosis, and their higher levels suggest the cardiac involvement. (Circ J 2007; 71: 1545 - 1550)