Granulomonocytic colony forming cells in myelofibrosis: concentrations within hepatic blood and peripheral blood

Hepatic and peripheral blood GM-CFC concentrations were compared in 8 cases of myelofibrosis. Hepatic blood concentrations were significantly higher (p less than 0.05). The density-distribution profile for hepatic blood GM-CFCs shifted to the left as compared to peripheral blood in 4 cases out of 5. The maximal blood transit time for circulating GM-CFCs was about 1 min. These results suggest that spleen and liver are a production site of blood GM-CFCs in myelofibrosis. In particular, they would be responsible for the presence in blood of the lightest GM-CFCs (less than 1.060 g cm-3). Increased GM-CFC inflow from bone marrow and/or liver and spleen to blood is the single explanation for the increased value of the circulating GM-CFCs.