Clonal CD5-positive B lymphocytes in myelodysplastic syndrome with systemic vasculitis and trisomy 8.
Bone marrow and peripheral blood from a myelodysplastic syndrome (MDS) patient with trisomy 8 and associated systemic vasculitis was investigated for clonal lymphoid lineage involvement using simultaneous metaphase and interphase fluorescence in situ hybridization (FISH) and immunocytochemistry with antibodies against CD13 (granulocytic), glycophorin A (GPA, erythroid), and the lymphocytic antigens CD3. CD5, CD20, and CD22. Trisomy 8 was detected in 55% of CD13+, 40% of GPA+, 6% of CD5+, and 5% of CD20/22+, but not in CD3+ cells. In a complementary experiment using interphase FISH on bone marrow cells sorted by flow cytometry, 13% of CD5/CD19 double-positive cells (76% purity) were found to be trisomic. The results indicate the existence of a small CD5-positive B-lymphoid clone as part of the MDS process in this patient. Since CD5/19-positive cells have been proposed to be autoantibody producing, this finding might be a clue to the pathogenesis underlying the propensity for MDS patients to develop immune-mediated complications.
Billström
R
R
Department of Medicine, University Hospital, Lund, Sweden.
Johansson
B
B
Strömbeck
B
B
el-Rifai
W
W
Larramendy
M
M
Olofsson
T
T
Mitelman
F
F
Knuutila
S
S
D001402:B-Lymphocytes / Q000276:immunology*; D001854:Bone Marrow Cells; D018956:CD5 Antigens / Q000032:analysis*; D002898:Chromosomes, Human, Pair 8; D002999:Clone Cells; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000150:complications / Q000235:genetics* / Q000473:pathology*; D014314:Trisomy / Q000473:pathology*; D014657:Vasculitis / Q000150:complications*
D018956:CD5 Antigens