Abstract
Colony stimulating or inhibiting functions of the adherent cells in the bone marrow of children with aplastic anemia were studied. Utilizing the adherent cell separation technique, the marrow cells from 6 children with aplastic anemia and 6 children with non-hematological diseases (controls) were separated into non-adherent cells (NA cells) and adherent cells (Ad cells). The culture was carried out according to the method of Robinson and Pike. The colony forming efficiency of the unseparated marrow cells and of the NA cells was compared. Mixed cultures of the unseparated marrow cells obtained from the patients with aplastic anemia and those from the control were performed. The functions of Ad cells were assessed by influence on colony formation of the NA cells in the mixed culture.
The results obtained were as follows:
1) In the controls, the colony counts of the unseparated cells and NA cells ranged from 106 to 244, from 86 to 313, respectively.
2) The patients with aplastic anemia showed remarkablly low colony formation by the both marrow cells: unseparated cells formed from 0 to 10 colonies and NA cells formed from 0 to 16 colonies.
3) When the marrow cells from the patients and controls were mixed, the colony counts reduced approximately to one fourth of the control marrow cells.
4) The Ad cells of the control subject stimulated colony formation of the NA cells of the control, while those from the patients with aplastic anemia inhibited colony formation of the NA cells of the control.
5) The Ad cells of the control stimulated a little colony formation of the NA cells from the patients, while those from the patients failed to stimulate colony formation. These results suggest that the defective function of the Ad cells in bone marrow may be a cause of secondary decrease of CFC.
