FIG. 1.

Stromal cell line support of primitive hematopoietic cells. (A) Cobblestone area-forming cell (CAFC) frequency of bone marrow (BM) mononuclear cells (MNCs) grown on stromal layer cell lines derived from five different cell lines representing adipogenic, osteogenic, and fibroblastic cells. (B) Long-term culture frequency of BM MNCs that had been cultured in noncontact conditions using the OP9 cell line as the stromal cell layer. (C) CAFC frequency of BM MNCs cultured in contact conditions in the presence of inhibitors of the Notch pathway (γ-secretase inhibitor), the Wnt pathway (Dickkopf-1), or the hedgehog pathway (Cyclopamine). All graphs represent the mean of three independent experiments, error bars represent SEM. *P<0.05.