The immunophenotype of different immature, myeloid and B-cell lineage-committed CD34+ hematopoietic cells allows discrimination between normal/reactive and myelodysplastic syndrome precursors.
Occurrence of phenotypic abnormalities in CD34(+) hematopoietic progenitor and precursor cells (HPC) and their major B-cell and nonlymphoid compartments has been frequently reported in myelodysplastic syndromes (MDS). Here, we analyze for the first time the numerical and phenotypic abnormalities of different maturation-associated subsets of bone marrow (BM) CD34(+) HPC from 50 newly diagnosed MDS patients in comparison to normal/reactive BM (n=29). Our results confirm the existence of heterogeneously altered phenotypes among CD34(+) HPC from MDS and indicate that such variability depends both on the relative distribution of the different subsets of CD34(+) HPC committed into the different myeloid and B-lymphoid compartments, and their immunophenotype (for example, higher reactivity for CD117 and CD13 and lower expression of CyMPO, CD64 and CD65 on CD34(+) immature and neutrophil precursors), a clear association existing between the accumulation of CD34(+) HPC and that of immature CD34(+) HPC. Interestingly, expansion of erythroid- and neutrophil-lineage CD34(+) cells is detected in low-grade MDS at the expense of CD34(+) plasmacytoid dendritic cell and B-cell precursors, while expansion of immature CD34(+) precursors occurs in high-grade MDS. On the basis of the number and severity of the phenotypic abnormalities detected, a scoring system is proposed that efficiently discriminates between normal/reactive and MDS CD34(+) HPC, the mean score significantly increasing from low- to high-grade MDS.
Matarraz
S
S
Servicio General de Citometría, Departamento de Medicina, Centro de Investigación del Cáncer, Instituto de Biología Molecular y Celular del Cáncer, CSIC-USAL, Universidad de Salamanca, Salamanca, Spain.
López
A
A
Barrena
S
S
Fernandez
C
C
Jensen
E
E
Flores
J
J
Bárcena
P
P
Rasillo
A
A
Sayagues
J M
JM
Sánchez
M L
ML
Hernandez-Campo
P
P
Hernandez Rivas
J M
JM
Salvador
C
C
Fernandez-Mosteirín
N
N
Giralt
M
M
Perdiguer
L
L
Orfao
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D001853:Bone Marrow / Q000473:pathology; D019070:Cell Lineage; D005260:Female; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000276:immunology*; D023461:Myeloid Progenitor Cells / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism; D011379:Prognosis
D018952:Antigens, CD34