Acute undifferentiated leukemia: implications for cellular origin and
clonality suggested by analysis of surface markers and immunoglobulin gene
rearrangement
A Raghavachar, CR Bartram, A Ganser, G Heil, E Kleihauer and B Kubanek
Although B cell leukemias and, recently, T cell leukemias can be identified
both by surface marker and molecular analysis, there remains a population
of acute undifferentiated leukemias (AUL) that cannot be allocated
definitively to a single cell lineage. AUL was diagnosed in nine patients
according to stringent criteria. We combined both immunologic and molecular
approaches to analyze further the ambiguous origin of AUL cells. Southern
blot analysis revealed rearranged Ig heavy-chain genes in seven patients
and indicated a biclonal or oligoclonal leukemic cell population in three
of them, including one case of AUL with translocation (4;11). Analysis of
cell surface markers showed expression of at least one early B
cell-associated antigen (BA- 1, BA-2, B4, UL-38) in six of these seven
patients, with coexpression of a myeloid antigen (VIM-2) in three patients.
Leukemic cells of two other patients neither exhibited Ig chain gene
rearrangements nor expressed B cell-associated antigens. T cell receptor
beta-chain genes showed germline configuration in all nine cases. Our
results demonstrate heterogeneity among AUL patients based on molecular and
surface marker analyses and suggest that most AUL blast cells are derived
from a precursor cell that shares phenotypic and genotypic characteristics
of early B cells with certain surface antigens of myeloid cells, in some
cases of AUL more than one abnormal cell clone or subclone may exist, and
the cellular origin, at least of some AULs exhibiting t(4;11), may be truly
B cell lineage committed.
Volume 68,
Issue 3,
pp. 658-662,
09/01/1986
Copyright © 1986 by The American Society of Hematology
