ABSTRACT
The cell surface protein CD93 is known to be involved in the regulation of phagocytosis and cell adhesion. Although typically membrane-bound, a soluble form of CD93 (sCD93) has recently been identified. Currently, however, the role of sCD93 in monocyte function is unknown. In the current study, we analyzed the functional effects of sCD93 on THP-1 monocytic cells and human primary monocytes. Various forms of recombinant human sCD93 were used to investigate the effects of this molecule on both human primary monocytes and a monocytic cell line, THP-1. We found that sCD93 induced differentiation of monocytes to macrophage-like cells, as evidenced by activated cell adhesion and increased phagocytic activities. In addition, this differentiation resulted in an enhanced response to TLR stimulation in terms of differentiation marker expression and proinflammatory cytokine production. Furthermore, sCD93 enhanced LPS-stimulated TNF-α production even prior to monocyte differentiation. To investigate a possible role for sCD93 in the pathogenesis of chronic inflammatory diseases, we assessed the concentration of sCD93 in synovial fluid from patients with rheumatoid arthritis and found it to be significantly increased compared with synovial fluid from patients with osteoarthritis. Together, these data revealed a function for sCD93 that may have implications in inflammation and inflammatory diseases including rheumatoid arthritis.
Subject(s)
Cell Differentiation/immunology , Membrane Glycoproteins/metabolism , Monocytes/cytology , Receptors, Complement/metabolism , Toll-Like Receptors/metabolism , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/metabolism , Cytokines/biosynthesis , Enzyme-Linked Immunosorbent Assay , Humans , Inflammation/immunology , Inflammation/metabolism , Membrane Glycoproteins/immunology , Monocytes/immunology , Monocytes/metabolism , Receptors, Complement/immunology , Recombinant Proteins , Reverse Transcriptase Polymerase Chain Reaction , Synovial Fluid/immunology , Synovial Fluid/metabolism , Toll-Like Receptors/immunologyABSTRACT
PURPOSE: The purpose of the study was to investigate fatigue, depression and sleep in young adult and middle-aged. METHOD: The convenient sample consisted of 415 subjects from 20 to 59 years old. Data were collected using a self-report questionnaire from July to October, 2001. The VAS-F and CES-D were utilized to measure the level of fatigue and depression. Sleep duration and sleep satisfaction were measured based on the subject's self-report. RESULT: The result of the study revealed that the level of fatigue and depression was higher among young adult than middle-aged. Considering age and gender, the level of fatigue and depression was higher among young adult women and middle-aged men. Depression and sleep satisfaction influenced on the fatigue. CONCLUSION: Health care providers need to concern about fatigue and depression in young adult women and middle-aged men. Especially, more concern and intervention programs are needed for young adult women and middle-aged men.