Increased apoptosis in bone marrow B lymphocytes but not T lymphocytes in myelodysplastic syndrome.
The hallmark of myelodysplastic syndrome (MDS) is enhanced apoptosis in myeloid, erythroid, and megakaryocytic cells in the bone marrow leading to ineffective hematopoiesis. Recent studies suggested that immunological and microenvironmental factors play a role in the pathophysiology of this disease. We report a significant increase in apoptosis in bone marrow B lymphocytes in MDS as compared to that found in acute myeloid leukemia and healthy controls. Furthermore, we demonstrate that patients with refractory anemia with excess blasts in transformation (RAEB-T) had apoptosis levels in lymphocytes similar to those seen in other subtypes of MDS. Our findings suggest that the alterations in B lymphocytes in the form of increased apoptosis can be seen in MDS and support the concept that immune modulation plays a role in the pathophysiology of MDS.
Department of Hematopathology, Box 72, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
Hesham M
HM
Amin
Iman
I
Jilani
Elihu H
EH
Estey
Michael J
MJ
Keating
Amanda L
AL
Dey
Taghi
T
Manshouri
Hagop M
HM
Kantarjian
Zeev
Z
Estrov
Jorge E
JE
Cortes
Deborah A
DA
Thomas
Francis J
FJ
Giles
Maher
M
Albitar
D017209:Apoptosis; D001402:B-Lymphocytes / Q000473:pathology*; D001854:Bone Marrow Cells / Q000473:pathology*; D006801:Humans; D018655:Lymphocyte Count; D009190:Myelodysplastic Syndromes / Q000473:pathology*; D013601:T-Lymphocytes / Q000473:pathology*