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Myeloma Plasma Cells (myeloma + plasma_cell)
Selected AbstractsPreclinical development of hybrid cell vaccines for multiple myelomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2007Renata Walewska Abstract Immunotherapy may provide alternative or supplementary treatment of multiple myeloma (MM). We propose that hybrid cells, formed by fusing professional antigen-presenting cells with malignant plasma cells, would induce immune responses capable of mediating tumour regression. The human B-lymphoblastoid cell line, HMy2, was fused in vitro with CD138+ bead-separated myeloma plasma cells from five patients with MM. The hybrid cell lines generated in these studies grew stably in tissue culture, and maintained their phenotypic and functional characteristics, providing self-renewing cell lines with potential for therapeutic vaccination. The hybrid cells stimulated allogeneic and autologous T-cell proliferative responses in vitro to a considerably greater degree than their respective parent myeloma plasma cells, and directly activated both CD4+ and CD8+ T-cell responses. The enhanced T-cell stimulation correlated with expression of CD80 on the hybrid cells, and was inhibited by CTLA4-Ig fusion protein. The hybrid cell lines expressed several tumour-associated antigens known to be expressed in myeloma. These data show that self-replicating cell lines with enhanced immunostimulatory properties and potential for therapeutic vaccination can be generated by in vitro fusion of ex vivo myeloma cells and B-lymphoblastoid cell lines. [source] Mobilisation of tumour cells along with CD34+ cells to peripheral blood in multiple myelomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5-6 2001Lene Meldgaard Knudsen Abstract:Background: Cells belonging to the malignant clone are found in the peripheral blood in myeloma patients. In order to minimise the content of tumour cells in the stem cell product it is crucial to perform stem cell harvest at a time when tumour cells in the peripheral blood are at a minimum. Objective: The aim of the study was to compare the mobilisation kinetics of normal CD34+ cells and myeloma plasma cells during mobilisation with either G-CSF alone or high-dose cyclophosphamide (HDCy) plus G-CSF. Design and methods: Morning blood samples were drawn each day during mobilisation from start of G-CSF or HDCy and to the end of leukapheresis, and were analysed by flow cytometry for content of CD34+ cells and myeloma plasma cells (CD38+ + CD45,). Tumour cells were also estimated by a patient-specific real-time polymerase chain reaction (PCR) method based on the 5, nuclease TaqMan technology. Results: Flow cytometry data from 16 patients showed concomitant mobilisation of CD34+ cells and myeloma plasma cells. Seven patients were mobilised twice; first with G-CSF alone and then with HDCy plus G-CSF. There was no difference between the two mobilisation regimens regarding tumour cell mobilisation kinetics. Real-time PCR was performed in one patient and confirmed the mobilisation of tumour cells at the time when CD34+ blood cells were at a maximum. Conclusions: Tumour cells are mobilised to the peripheral blood at the same time as CD34+ cells in multiple myeloma patients after priming with both G-CSF alone and HDCy in combination with G-CSF. [source] Soluble urokinase-type plasminogen activator receptor (suPAR) as an independent factor predicting worse prognosis and extra-bone marrow involvement in multiple myeloma patientsBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2003Gian Matteo Rigolin Summary. The urokinase-type plasminogen activator (uPA) system, which consists of a proteinase (uPA), a receptor (uPAR or CD87) and inhibitors, is involved in proteolysis, cell migration, tissue remodelling, angiogenesis and cell adhesion. Recent findings suggest that malignant plasma cells express uPA and uPAR. The expression of these factors could represent a process by which myeloma plasma cells interact with the bone marrow (BM) environment and influence important biological events such as bone matrix degradation, plasma cell invasion and homing and, possibly, clinical evolution. We evaluated uPAR (CD87) and its soluble form (suPAR) in 49 multiple myeloma (MM) patients and correlated their expression and levels with clinico-biological characteristics of the disease. Flow cytometric analysis demonstrated that CD87 was expressed in all MM patients. High CD87 expression was associated with higher intensity of expression of CD56 (P = 0·038), CD38 (P = 0·058) and CD138 (P = 0·054) and CD45bright positivity (P = 0·014). suPAR levels correlated positively with soluble serum CD138 (P = 0·001), creatinine (P = 0·001), beta2 -microglobulin (P < 0·001), disease stage (P = 0·017) and extra-BM involvement (P = 0·002). In the 46 evaluable patients, multivariate analysis showed that high levels of suPAR (P = 0·0214) and disease stage (P = 0·0064) were predictive of extra-BM involvement. In multivariate Cox analysis, 13q deletion (P = 0·0278), high soluble serum CD138 (P = 0·0201) and high suPAR (P = 0·0229) were the only parameters that independently affected survival. We conclude that CD87 is expressed on myeloma plasma cells and that suPAR, which predicts extra-BM involvement and poor prognosis, possibly represents a molecule with a relevant role in the biology of MM. [source] |