TUMOR-NECROSIS-FACTOR AND INTERLEUKIN-1 INDUCE ACTIVIN-A GENE-EXPRESSION IN A HUMAN BONE-MARROW STROMAL CELL-LINE

Activin A, a homodimer of theβ A chain, regulates hematopoiesis. In a human bone marrow-derived stromal cell line, KM-102, phorbol myristate acetate, tumor necrosis factor- α and interleukin -1β induced great increases in β A chain mRNA levels and production of activin A activities. The phorbol ester-induced β A chain gene expression was inhibited by cycloheximide and down regulation of protein kinase C, whereas the cytokine-induced expression was little affected by these treatments. These results indicate that the inflammatory cytokines directly stimulate β A chain gene expression via protein kinase C-independent pathways. © 1992.