Stem Cells, Vol 11, 536-542, Copyright © 1993 by AlphaMed Press
Absence of bcr/abl gene in single hemopoietic progenitors in some patients with chronic myelogenous leukemia
M Misawa, H Maeda, H Hara, Y Yamamoto and J Furuyama
Department of Blood Transfusion, Hyogo College of Medicine, Japan.
CD34+DR- and CD34+DR+ cells were isolated from the marrow mononuclear cells
of five patients with chronic myelogenous leukemia (CML) carrying the
Philadelphia (Ph) chromosome. Analysis of bcr/abl hybrid mRNA in individual
colonies from a single cell using reverse transcriptase polymerase chain
reaction (RT-PCR) demonstrated the presence or absence of the hybrid mRNA.
For patient 1 in the chronic phase of CML, the hybrid mRNA was detected in
all colonies derived from CD34+DR+ and CD34+DR- hemopoietic progenitors. In
contrast, for patient 2 in the chronic phase of CML, the mRNA was detected
in all individual colonies from CD34+DR+ progenitors but not in any from
CD34+DR- progenitors. For patient 3 in the chronic phase of CML, the mRNA
was detected in all individual colonies from CD34+DR+ but in only some of
the colonies from CD34+DR- progenitors. For patients 4 and 5 in the acute
crisis of CML, the mRNA was found in a portion of colonies from CD34+DR+
and CD34+DR- progenitors. These results indicated that normal clones can
persist in CD34+DR- progenitors in some patients with CML, even when
chromosome analysis detects the Ph chromosome in all metaphases of bone
marrow cells.
