Bone marrow B lymphocytes in multiple myeloma and MGUS: Focus on distribution of naïve cells and memory subsets.

Background/aims: Multiple myeloma (MM) is caused by proliferation of clonal plasma cells (cPCs) in bone marrow (BM), associated with numerical and functional defects in immune subsets. An impairment of B cell compartment is involved in onset/progression of the disease.

Methods: By flow cytometry, we studied distribution of naïve/transitional (IgD(+)CD27(-)), memory unswitched (IgD(+)CD27(+)), memory switched (IgD(-)CD27(+)) and double negative (DN) (IgD(-)CD27(-)) B lymphocytes in BM of control subjects, and responding and relapsing patients.

Correlation between CD117+ myeloma plasma cells and hematopoietic progenitor cells in different categories of patients.

Background: Multiple myeloma (MM) is a neoplastic disorder of plasma cells interesting mainly the elderly. MM remains an incurable disease, mostly because of the strong interplay between clonal plasma cells (cPCs) and bone marrow (BM) microenvironment. Multiparameter flow cytometry (MFC) allows the simultaneous study of the cPC immunophenotype and alterations involving other cells in BM, but rarely these data are interpreted as connected.