Bladder carcinoma cell line KU-19-19-derived cytokines support proliferation of growth factor-dependent hematopoietic cell lines: modulation by phorbol ester, interferon-gamma and interleukin-1 beta.

The human bladder carcinoma cell line KU-19-19 synthesizes and secretes hematopoietic growth factors. Conditioned medium (CM) from KU-19-19 stimulated the [3H]thymidine incorporation of growth factor-dependent hematopoietic cell lines. ELISA documented high amounts of granulocyte colony-stimulating factor (G-CSF; > 5 ng/ml); also granulocyte-macrophage CSF (GM-CSF), macrophage-CSF (M-CSF), stem cell factor (SCF), IL-6, and IL-8 were detected in KU-19-19 CM. Pretreatment with phorbol ester, IL-1 beta, or IFN-gamma increased the level of G-CSF, GM-CSF, and M-CSF in KU-19-19 CM. Thus, KU-19-19 represents a reliable source for purification of G-CSF and can easily be used to support proliferation of growth factor-dependent cell lines. The ability to respond to different stimuli suggests that several regulatory pathways may be involved in cytokine production of this bladder carcinoma cell line.