Granulocytic colony forming cells in vitro: II. Patients with aplastic anaemia

Abstract

Several drugs and other external agents are thought to play an aetiological role in the development of aplastic anaemia [2]. Despite these aetiological factors the clinical picture is characterized uniformly by an acute or chronic bone marrow failure with fatty replacement of the haemopoietic tissue and peripheral pancytopenia. The pathogenesis of this disease most probably points to disturbances of the haemopoietic cell reneval system [1]. It is the purpose of this short communication to present data on the concentration of granulocytic progenitor cells (colony forming cells in vitro = CFC's) in aplastic anaemia and to compare these findings with those in acute agranulocytosis. Material and Methods Patienls 25 patients with aplastic anaemia at different stages were examined by means of an in vitro culture technique in order to assess the concentration of CFC's. A few of the patients were studied at different intervals during their follow-up in the clinic. The haematological data as well as the in vitro results of bone marrow and peripheral blood cultures in 22 patients are described in detail elsewhere [4]. A similar analysis was performed in 1] patients with acute agranulocytosis and those recovering from it. The individual data were reported by Heir et al. in this issue. As controls we studied the peripheral blood of healthy blood donors and marrow specimens from patients without disturbances in granulopoiesis. In vitro culture technique After dextran-sedimentation of bone marrow aspirates the leukocyte-rich supernatant was harvested, the cells were washed twice and resuspended in tissue culture medium. The double layer agar culture system described by Robinson & Pike (1971) [5] was used. Feeder layers of a defined white blood cell composition were prepared, in order to obtain optimal colony stimulating activity (CSA) [3]. After 10 days of incubation all aggregates of more than 50 cells were counted as colony using a dissecting microscope.