The result of bone marrow granulocyte-macrophage progenitors（GM-CFC） culture in vitro in 12 patients with aplaotic anemia

Assessment of bone marrow granulocyte-macrophage progenitors （GM-CFC） was performed by a single layer agar gel culture in vitro. The GM-CFC incidence of 2×10~5 plated cells was 152.1±18.3（mean±SE） in 15 normal controls and 8.02±2.5 in 12 patients with aplaotic anemia respectively. The incidence ratio of patients to normal controls was 0-5.1％ in 9 out of the 12 patients. Bone marrow cells from 10 patients were co-cultivated with normal bone marrow cells for thirteen,times, with a result of that the actual counts in three co-cultures were only about 40％ of the expected counts. However, it can not be concluded that there were supressing cell in patients′ bone marrow, because no supression was found in co-cultures of the same three patients before therapy. To determine the effect of patients′ serum on normal bone marrow culture, cells from normal bone marrow were cultured by adding 4 drops of patient′s serum per plate. The actual incidence was 99.1—285％ of the control′s incidence in 14 cultures. It suggests that most patients with aplastic anemia have elevated levels of colony stimulating factors in their serum.