マウス骨髄細胞の長期培養により形成された吸着細胞層によるコロニー刺激因子の産生

Abstract

Conditioned medium prepared from adherent cells in long-term culture of mouse bone marrow stimulated in vitro colony formation by mouse bone marrow cells. Colonystimulating activity (CSA) was detected in the medium from 12-week-old cultures, and increased weekly to reach a plateu level 25 weeks after initiation of cultures. The CSA level was maintained over a 40-week period. The cultures were not recharged with fresh bone marrow cells throughout the experiment, and then no non-adherent cell production was observed in them. Two types of colony-stimulating factor were separated by gel filtration on Ultro-gel AcA 34 column. The larger molecular weight component that was heat-stable and trypsinresistant stimulated macrophage colony formation. The smaller molecular weight component that was heat-labile and trypsin-sensitive stimulated granulocyte colony formation.