BACKGROUNDThere were only 3 multiple myeloma (MM) cell lines established in China. In this study, we succeeded in establishing a novel MM cell line and analyzed its biological characteristics.

METHODSMononuclear cells isolated from the peripheral blood (PB) and bone marrow (BM) of a patient with advanced MM (lambda light chain type) were cultured in medium. Cell morphology was analyzed by Wright-Giemsa-staining and cytochemical staining, immunophenotyping by flow cytometry and cytogenetic analysis by chromosome RHG-banding technique. Quantitative fluorescent polymerase chain reaction (PCR) was used to detect Epstein - Barr virus (EBV) DNA.

RESULTSThe established cell line could survive and proliferate in the presence of feeder cells or conditioned medium. The cells secreted lambda light chain and were negative for EBV. The Wright-Giemsa-staining showed typical plasmablast or plasma cell morphology. The cytochemical staining of the cells showed the following reactivity patterns: positive for acid phosphatase, negative for myeloperoxidase. The immunoprofile of the cells was concordant with that of MM cells: positive for CD10, CD28, CD38, CD138, CD56, CD49d, CD44, CD54 and CD58, negative for CD19, CD40, CD95, CD95L, CD34, CD2 and CD5. The cytogenetic analysis showed complex chromosome abnormality of i (1q+), 8q+, 13q+, i (17q), i (18q) and +M. There was no difference in morphology, immunophenotype and cytogenetics between cells from PB and BM.

CONCLUSIONSAn MM cell line secreting lambda light chain named CZ-1 was established. The cells from both PB and BM have the same biological characteristics.