EXPRESSION OF ACUTE-PHASE PROTEINS BY BONE-MARROW STROMAL CELLS

The current work examines the expression of acute phase genes in a mur ine-derived bone marrow stromal cell model (BMS2) which exhibits adipo cyte and osteoblast characteristics and supports lymphopoiesis in vitr o. Each of these physiologic processes is responsive to inflammatory e vents such as endotoxemia. Exposure of BMS2 cells to pro-inflammatory cytokines induced the expression of the serum amyloid A and complement factor B. During adipocyte differentiation, expression of complement C3, complement factor D (adipsin), and angiotensinogen increased in a time dependent manner. The bone metabolic steroid, 1,25 dihydroxy vita min D-3, specifically induced complement C3 expression in a time- and dose-dependent manner. Based on get retention analysis, BMS2 nuclear e xtract contained proteins recognizing specific response elements from the complement C3, angiotensinogen, and complement factor B promoters. These results suggest that the bone marrow's repertoire of acute phas e proteins is dependent on the stromal cell's phenotype or activation state.