Phenotypic characterization of the human myeloma cell growth fraction.
In this study we quantified the proliferation rate of normal and malignant plasma cells (PCs) by ex vivo incorporation of 5-bromo-2'-deoxyuridine (BrdU; labeling index, LI) using flow cytometry. We show that all bone marrow PCs, either normal or malignant, include a subset of proliferating PCs present within the CD45(bright) fraction. Indeed, medullary normal and malignant PCs were always heterogeneous for CD45 expression, and proliferation was always restricted primarily to the CD45(bright) compartment. Moreover, an inverse correlation was found between LI or CD45 and B-cell lymphoma 2 (Bcl-2) in both malignant and normal PCs, the most proliferating CD45(bright) PCs have the lowest Bcl-2 expression. We investigated expression of molecules of interest in multiple myeloma (MM)-that is, CD138, CD19, CD20, CD27, CD28, CD56, and CD11a-to further characterize the CD45(bright) fraction. Among all of these molecules, only CD11a was exclusively expressed by CD45(bright) proliferating myeloma cells. In conclusion, proliferating myeloma cells are characterized by the specific CD45(bright) CD11a(pos) Bcl-2(low) phenotype.
Robillard
Nelly
N
Institut National de la Santé et de la Recherche Médicale UMR601, Département de Recherche en Cancérologie, Nantes, France.
Pellat-Deceunynck
Catherine
C
Bataille
Régis
R
D000911:Antibodies, Monoclonal / Q000737:chemistry; D017209:Apoptosis; D001854:Bone Marrow Cells / Q000166:cytology; D001973:Bromodeoxyuridine / Q000494:pharmacology; D040881:CD11a Antigen / Q000096:biosynthesis; D049109:Cell Proliferation; D002469:Cell Separation; D004396:Coloring Agents / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D017493:Leukocyte Common Antigens / Q000096:biosynthesis / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000378:metabolism; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology*; D014066:Palatine Tonsil / Q000166:cytology / Q000378:metabolism; D010641:Phenotype; D010950:Plasma Cells / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000737:chemistry / Q000378:metabolism
D000911:Antibodies, Monoclonal; D040881:CD11a Antigen; D004396:Coloring Agents; D019253:Proto-Oncogene Proteins c-bcl-2; D017493:Leukocyte Common Antigens; D001973:Bromodeoxyuridine