INDUCTION OF BCL-2 GENE-EXPRESSION BY INTERCELLULAR INFORMATION FROM HEMATOPOIETIC SUPPORTIVE STROMAL CELLS TO DA-1 CELLS

When Interleukin-3 (IL-3) dependent DA-1 cells were cultured on hemopoietic supportive stromal cells (MS-5), DA-1 cells survived and proliferated in the absence of detectable IL-3. Although IL-3 was not produced by the MS-5 cells, their production of granulocyte-macrophage colony-stimulating factor (GM-CSF) was increased when they were co-cultured with DA-1 cells. This suggests that DA-1 cells transmit signals to stromal cells that enhance growth factor(s) production. Expression of bcl-2 by DA-1 cells was induced when they were co-cultured with MS-5 cells, suggesting that DA-1 cells express bcl-2 strongly in response to a signal produced by MS-5 cells. These data indicate the existence of a two-way interaction between DA-1 cells and hemopoietic supportive stromal cells. (C) 1994 Wiley-Liss, Inc.