Ways of expressing results of human bone marrow progenitor cell culture

In human bone marrow culture studies the number of granulocyte progenitor cells (CFUc) is expressed as the number of colonies per 10(5) incubated, nucleated cells. However, this provides little information on cell proliferation kinetics of granulopoiesis. The ratio of progenitors (CFUc) to end cells (metamyelocytes or granulocytes) is related to the effectiveness of granulopoiesis and this allows an estimate to be made of an amplification factor within the maturing and proliferating compartments. We measured an index equal to the number of CFUc per 10(5) falls when a large number of granulocytes is produced by each progenitor cell. This was observed in many patients with a neutropenia. An estimation of the total number of metamyelocytes is based on the ratio of the number of metamyelocytes to the number of blood granulocytes. This allows an estimate of the total number of CFUcs, which is of clinical interest.