Abstract
Serum colony-stimulating activity (CSA) levels were determind in 10 normal individuals and 18 patients with aplastic anemia. CSA was assayed by the agar single layer culture technique using bone marrow cells of the ddN female mice as a source of CFU-C. Number of colonies produced after 7 days' incubation of the bone marrow cells at 37°C, in a humidified atmosphere flushed with air containing 10 % CO2 was regarded as CSA. CSA was not verified in all sera from 10 normal individuals, while CSA was significantly increased in sera from 15 out of 18 patients with aplastic anemia of clinical stage less than II.
No significant CSA was detected in serum from a patient with aplastic anemia in complete remission (clinical stage III) similarly to normal individuals.
In patients with aplastic anemia, CSA levels was not significantly correlated to any of the follows : clinical stages, Hb levels, granulocyte or monocyte counts in peripheral blood.
In two patients treated with both androgen and prednisolone, CSA levels tend to be less than that of the other patients treated with androgen alone. Otherwise, it is noted in these patients that various types of treatment seems to show no significant effect on CSA levels.
CSA-stimulating activity (CSA-SA) was verified in sera both from normal individuals and patients with aplastic anemia. There was no significant difference in levels of CSA-SA between normal individuals and patients with aplastic anemia.
From these results, the significance of CSA and CSA-SA in the regulation of in vivo granulopoiesis in aplastic anemia was discussed.
