Occurrence of the common acute lymphoblastic leukemia antigen on blast
cells of a patient with chronic myelomonocytic leukemia in non-lymphoid
blastic phase
V Gressler, M Garbrecht and DK Hossfeld
Leukemias showing a conspicuous lymphoid phenotype, ie, those that are
HLA-DR positive, common acute lymphoblastic antigen (cALLA) positive,
terminal deoxynucleotidyl transferase (TdT) negative, as well as
myeloperoxidase positive (MPO), could be considered so-called mixed
leukemias. Leukemias with biphenotypic blasts have to be distinguished from
cases comprising two separate subpopulations that express different
lineage-associated characteristics. By use of a simple new method
(Immunogold Staining) we examined a case of chronic myelomonocytic leukemia
in blastic phase and demonstrated simultaneous staining for
MPO/alpha-naphthyl-esterase and expression of the HLA-DR- positive,
cALLA-positive, and TdT-negative phenotype. The cALL antigen was detected
only on mono- and myelo-monoblasts; its expression was inversely related to
the MPO positivity, and it disappeared together with these types of blasts
after chemotherapy. On the basis of our findings it remains obscure whether
the cALL antigen at the initial presentation was due to the immature
monocytic features of the leukemic cells or disclosed on additional
lymphoid differentiation pattern of the blasts.
Volume 66,
Issue 6,
pp. 1482-1484,
12/01/1985
Copyright © 1985 by The American Society of Hematology
