International Journal of Cell Cloning, Vol 1, 230-239, Copyright © 1983 by AlphaMed Press
Pluripotent hemopoietic progenitors (CFU-GEMM) in chronic myelogenous leukemia
J Lepine and HA Messner
Human hemopoietic pluripotent progenitors form multilineage colonies when
cultured in methylcellulose with medium conditioned by leukocytes in the
presence of phytohemagglutinin (PHA-LCM) and erythropoietin (EPO). We have
examined their frequency, culture requirements and proliferative activity
in 20 peripheral blood and 29 bone marrow specimens from patients with CML
in chronic phase. Multilineage colonies developed under regular culture
conditions in approximately 50% of all samples. The frequency ranged from
1-36 per 2 X 10(5) mononuclear cells of density less than 1.077 gm/ml. The
requirements for PHA-LCM and EPO varied for patients with CML when compared
to normal individuals; i.e., cells from some patients gave rise to mixed
colonies with substantial erythroid components in the absence of PHA- LCM
or without addition of the usually required EPO concentrations. The
proliferative activity of CFU-GEMM was assessed using a short-term exposure
to tritiated thymidine (3HTdR) prior to plating. The plating efficiency in
all bone marrow and peripheral blood samples was reduced to 40-70% of the
unexposed controls. In contrast, the plating efficiency after exposure to
3HTdR in normal individuals usually ranged from 70-90% of controls for bone
marrow samples and from 85-100% of controls for peripheral blood samples.
Thus, an increased proliferative rate of pluripotent hemopoietic
progenitors is a consistent feature of CML patients. In addition, at least
in some patients, different requirements for erythropoietin or PHA-LCM were
observed when compared to normal culture conditions.
