Binding of the differentiation-inducer, granulocyte-colony-stimulating factor, to responsive but not unresponsive leukemic cell lines

Abstract

Granulocyte-colony-stimulating factor (G-CSF) is a tissue-derived 25,000 M(r) glycoprotein that stimulates neutrophilic granulocyte colony formation from murine bone marrow progenitor cells in vitro. It is also a potent inducer of terminal differentiation and suppressor of stem cell renewal in the murine myelomonocytic leukemic cell line WEH1-3B. Purified G-CSF was radioiodinated to high specific radioactivity with retention of full biological activity. Iodinated G-CSF bound specifically to WEH1-3B cells, J774 macrophage tumor cells, and normal murine bone marrow cells but not to a variety of other tumor cell lines or murine thymocytes. WEH1-3B cells showed a high affinity for 125I-labeled G..