scholarly journals The Novel ADCC-Optimized Human CD54 (ICAM-1) Antibody MSH-TP15e Has Potent Anti-Myeloma Activity

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4471-4471
Author(s):  
Katja Klausz ◽  
Renate Burger ◽  
Christian Kellner ◽  
Andreas Guenther ◽  
Matthias Peipp ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Nk Cells ◽  
Cell Lines ◽  
Plasma Cells ◽  
Xenograft Model ◽  
The Novel ◽  
Single Chain ◽  
Myeloma Cells ◽  
Number Of Patients

Abstract Background: Monoclonal antibodies directed against various target antigens have proven efficacy in cancer therapy including hematological malignancies. Recently, daratumumab and elotuzumab became the first antibodies approved for the treatment of multiple myeloma (MM). Due to the substantial number of patients still in need for long-term disease control, the investigation of additional target structures and potent molecule formats for antibody-based therapy of MM remains important. Methods: Human synthetic single-chain fragment variable (scFv) phage display libraries were subjected to a cellular screening approach. The MSH-TP15 clone was selected based on its binding to various MM cell lines and patient-derived CD138-positive malignant plasma cells. Intercellular adhesion molecule-1 (ICAM-1/CD54), known to be important for the interaction of malignant plasma cells with the bone marrow microenvironment, was identified as target antigen. Based on the scFv sequence, fully human IgG1 antibody variants with selected mutations in the Fc domain were constructed to generate wild-type, antibody-dependent cell-mediated cytotoxicity (ADCC)-optimized and Fc-knockout variants. First, these variants were analyzed for their capacity to kill MM cells in vitro. Apoptosis induction and growth inhibition were tested by flow cytometry and in MTS proliferation assays. ADCC and complement-dependent cytotoxicity were investigated in chromium-release assays using human serum, peripheral blood mononuclear cells or purified NK cells of healthy donors. In vivoefficacy of an ADCC-optimized variant was analyzed in the INA-6 myeloma xenograft model. Results: The MSH-TP15 antibodies target an epitope on the N-terminal part of the extracellular domain of human ICAM-1/CD54. The antibody variants showed no anti-proliferative effects on patient-derived bone marrow stromal cells, nor directly induced apoptosis or inhibited proliferation of myeloma cells. While complement-dependent cytotoxic activity was generally absent, the Fc-engineered antibody variant MSH-TP15e significantly triggered ADCC against various MM cell lines and freshly isolated patient myeloma cells. The recruitment of human NK cells was crucial for the cytotoxic effects observed in vitro. Importantly, an ADCC-optimized variant completely prevented tumor engraftment in the INA-6 xenograft model. Conclusions: The novel ADCC-optimized fully human antibody MSH-TP15e directed against ICAM-1/CD54 exerts potent anti-myeloma activity in vitro and in vivo. Therefore, it has promising characteristics and will be further evaluated for MM immunotherapy. Disclosures Guenther: Novartis: Consultancy, Honoraria; Celgene: Honoraria; Takeda: Consultancy, Honoraria.

Mcl-1 Is Overexpressed in Multiple Myeloma and Correlates with Disease Severity.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1419-1419
Author(s):  
Soraya Wuilleme-Toumi ◽  
Nelly Robillard ◽  
Patricia Gomez-Bougie ◽  
Philippe Moreau ◽  
Steven Le Gouill ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Disease Severity ◽  
Cell Lines ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Lymphocytic Leukemia ◽  
Myeloma Cells

Abstract Multiple Myeloma (MM) is a fatal malignancy of B-cell origin characterized by the accumulation of plasma cells within the bone marrow. The expression of the pro-survival members of the Bcl-2 family has been shown to be a key process in the survival of myeloma cells. More particularly, Mcl-1 expression turned out to be critical for their survival. Indeed, knockdown of Mcl-1 by antisenses induces apoptosis in myeloma cells. Finally, Mcl-1 was found to be the only anti-apoptotic Bcl-2 family member which level of expression was modified by cytokine treatment of myeloma cells. For these reasons, we have evaluated the expression of Mcl-1 in vivo in normal, reactive and malignant plasma cells (PC) i.e., myeloma cells from 55 patients with MM and 20 human myeloma cell lines using flow cytometry. We show that Mcl-1 is overexpressed in MM in comparison with normal bone marrow PC. Forty-seven percent of patients with MM at diagnosis (p=.017) and 80% at relapse (p=.014 for comparison with diagnosis) overexpress Mcl-1. Of note, only myeloma cell lines but not reactive plasmocytoses have abnormal Mcl-1 expression, although both plasmocyte expansion entities share similar high proliferation rates (>20%). Of interest, Bcl-2 as opposed to Mcl-1, does not discriminate malignant from normal PC. This shows that the overexpression of Mcl-1 is clearly related to malignancy rather than to proliferation. It will be important to know whether the overexpression of Mcl-1 is related to an abnormal response to cytokines like Interleukin-6 or to mutations of the promoter of the Mcl-1 gene as already described in B chronic lymphocytic leukemia. Finally, level of Mcl-1 expression is related to disease severity, the highest values being correlated with the shortest event-free survival (p=.01). In conclusion, Mcl-1 which has been shown to be essential for the survival of human myeloma cells in vitro is overexpressed in vivo in MM and correlates with disease severity. Mcl-1 represents a major therapeutical target in MM.

Expression of CD21 antigen on myeloma cells and its involvement in their adhesion to bone marrow stromal cells

Blood ◽  
1995 ◽  
Vol 85 (12) ◽  
pp. 3704-3712 ◽  
Author(s):  
N Huang ◽  
MM Kawano ◽  
MS Mahmoud ◽  
K Mihara ◽  
T Tsujimoto ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Lines ◽  
Stromal Cells ◽  
Plasma Cells ◽  
Cell Types ◽  
Myeloma Cell ◽  
Adhesion Assay ◽  
Myeloma Cells ◽  
Stromal Cell Line

The mature myeloma cells express very late antigen 5 (VLA-5) and MPC-1 antigens on their surface and adhere to bone marrow (BM) stromal cells more tightly than the VLA-5-MPC-1-immature myeloma cells in vitro. The VLA-5 and MPC-1 antigens possibly function as two of the molecules responsible for interaction of mature myeloma cells with BM stromal cells. However, the immature myeloma cells do interact with BM stromal cells, and it is unclear which adhesion molecules mediate their interaction. In this study, we found that both immature and mature myeloma cells expressed CD21, an adhesion molecule known to bind to CD23. CD21 was also detected on normal plasma cells. To evaluate the role of CD21 expression on myeloma cells, two myeloma cell lines, NOP-2 (VLA-5-MPC-1-) and KMS-5 (VLA-5+MPC-1+), were used as representatives of immature and mature myeloma cell types, respectively, and an adhesion assay was performed between the myeloma cell lines and BM stromal cells. Antibody-blocking results showed that adhesion of the mature type KMS-5 to KM102, a human BM-derived stromal cell line, or to short-term cultured BM primary stromal cells was inhibited by monoclonal antibodies (MoAbs) against CD21, VLA-5, and MPC-1, and inhibition of adhesion of the immature type NOP-2 to KM102 by the anti-CD21 MoAb was observed as well. Furthermore, CD23 was detected on KM102. Treatment of KM102 with an anti-CD23 MoAb also inhibited adhesion of either KMS-5 or NOP-2 to KM102. Therefore, we propose that CD21 expressed on myeloma cells likely functions as a molecule responsible for the interaction of immature myeloma cells as well as mature myeloma cells with BM stromal cells, and CD23 may be the ligand on the stromal cells for the CD21-mediated adhesion.

scholarly journals Myeloma-Specific Oncolytic Adenovirus Induces Significant Tumour Oncolysis In Vitro and In Vivo and Prevents Cell Line Regrowth

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3213-3213
Author(s):  
Georgia Rose Stewart ◽  
Simon Tazzyman ◽  
Darren Lath ◽  
Jenny Down ◽  
John A Snowden ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Death ◽  
Cell Lines ◽  
Plasma Cells ◽  
Residual Disease ◽  
Xenograft Model ◽  
Annexin V ◽  
Myeloma Cell ◽  
Healthy Donors

Abstract Multiple myeloma is a largely incurable disease and despite current therapies achieving good initial responses, patients frequently relapse. Therefore, new approaches are required that not only reduce the tumour load, but also prevent the growth of residual disease. One such approach is the use of oncolytic viruses. We developed an oncolytic adenovirus that utilizes transcriptional control of E1A under the myeloma-specific promoter CS1 (ADCE1A). We hypothesised that ADCE1A would be myeloma-specific, inducing tumour oncolysis and preventing tumour regrowth. A panel of myeloma cell lines (JJN3, L-363, OPM-2, U-266, RMPI-8226, NCI-H929, KMS-11, KMS-12-BM) were assessed for expression of CS1 by flow cytometry (FC). The same panel were treated with ADCE1A and cell death was monitored after 72 hours using FC and propidium iodide staining. Apoptosis was assessed following ADCE1A infection using annexin V staining and analysed by FC at 6 and 24 hours post treatment. CD138+ plasma cells from bone marrow aspirates were obtained from myeloma and plasma cell leukaemia patients and from the peripheral blood from healthy donors. The CD138+ and CD138- populations from these samples were treated with ADCE1A and cell death was monitored after 4 days using FC and propidium iodide staining. Myeloma cell regrowth was assessed after bortezomib (0.56-2.81nM) or bortezomib in combination with ADCE1A treatment using cell counts. Viral efficacy was tested in a xenograft model of myeloma, where 5 weeks after tumour cell injection (106 U266 cells intravenously), mice were treated with ADCE1A (1x107 pfu, 2x/wk) or control (PBS) for 3 weeks. Tumour burden was measured ex vivo in bone marrow flushes of the long bones by FC. CS1 was expressed in all myeloma cell lines, except KMS-12-BM. ADCE1A infected, replicated and caused oncolysis in JJN-3, L-363, OPM-2, U-266, RPMI-8226, NCI-H929, and KMS-11 myeloma cell lines. However, KMS-12-BM had the lowest sensitivity to ADCE1A. This correlated with CS1 expression, as CS1 was not expressed at the protein level in this cell line. Apoptosis, as detected by annexin V staining, was found to be a cell death mechanism involved in ADCE1A oncolysis. Importantly, ADCE1A induced oncolysis in primary patient malignant CD138+ plasma cells, but not in the non-malignant CD138- bone marrow mononuclear population from these patients. Additionally, ADCE1A had no effect on cell death in non-malignant CD138+ plasma cells and non-malignant CD138- peripheral blood mononuclear population from healthy donors. ADCE1A prevented regrowth of myeloma cell lines following treatment with bortezomib in vitro. In the U266 xenograft model, tumour load was significantly reduced (p<0.05) compared to control treated mice. In summary, ADCE1A has potential clinical efficacy as shown by preclinical models and patient tumour samples. Additionally, ADCE1A was able to stop tumour cell regrowth after chemotherapy in vitro, therefore, the use of oncolytic adenoviruses to target minimal residual disease may be a novel yet promising approach for the treatment of myeloma. Disclosures Snowden: Jannssen/J&J: Other: Speaker fees; Jazz & Sanofi: Other: Speaker fees at ASH.

Identification of Vacuolar H+- ATPase as a Target for Myeloma Therapeutics.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 257-257
Author(s):  
Yuan Xiao Zhu ◽  
Chung Xin ◽  
Sheng Ben Liang Lian ◽  
Wee-Joo Chng ◽  
Suzanne Trudel ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Viability ◽  
Cell Lines ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Normal Donor ◽  
Bafilomycin A1 ◽  
Myeloma Cells ◽  
Treatment Conditions

Abstract From a high throughput RNAi screen of the human druggable genome targeting the KMS11 cell line, we identified the suppression of the vacuolar H+- ATPase (V-ATPase) family as cytotoxic to myeloma cells. In the screen, two oligos against each gene for the V-ATPase subunits ATP6V1A and ATP6V1B1 resulted in suppression of cell growth (50% and 60% inhibition of cell viability respectively). We further confirmed this result using both lentiviral shRNA knockdown and two small molecule inhibitors specific for V-ATPase. Silencing of ATP6V1A by lentiviral shRNA knock-down in KMS11 and in OPM1 myeloma cell lines caused 75–80% reduction of cell viability at 5 days post infection (measured by MTT assay). Consistent with this result, the V-ATPase specific inhibitors, bafilomycin A1 and REATA 203, both inhibited the growth of a genetically heterogeneous and standardized panel of 14 human myeloma cell lines in vitro with an IC50 ranging from 2.2 – 8.9 nM (mean 5.25 nM) for bafilomycin A1 and 46–1594 nM (mean 542.5 nM)) for REATA 203. We further demonstrated that patient samples (n=10) were sensitive to 20nM bafilomycin A1 which induced a mean of 58% of MM cells to undergo apoptosis (range 10% to 93%) after 24 hours of treatment. Similar to bafilomycin A1, treatment of primary patient-derived MM cells with 500 nM REATA 203 for 72 hours resulted in a mean 69% apoptosis (range 24% to 97%). In contrast, non-myeloma cells (the CD138- fractions of the bone marrow samples) were less sensitive - mean 9% apoptosis (range from 0% to 34%) under the same treatment conditions. Of high interest, however, unlike most drugs we have studied in pre-clinical myeloma models, the cytotoxicity induced by bafilomycin A1 in MM cell lines is abrogated by co-culture with patient bone marrow stromal cells but is not affected by IL-6 or IGF-1 treatment. Dexamethasone- or melphalan-resistant MM cell lines were also highly sensitive to both bafilomycin A1 and REATA 203. In a xenographic JJN3 mouse model, bafilomycin A1 suppresses and delays growth of tumor in a dose-dependent fashion. Gene expression analysis of normal-donor bone marrow plasma cells (n=19), primary tumor samples from MM patients (n=107) and normal somatic tissues demonstrates ubiquitous expression of most subunits of V-ATPase, however, some subunits are preferentially expressed in myeloma cells compared with normal plasma cells, including ATP6V1F (84% vs. 11%), ATP6V1E1 (29% vs. 5%), ATP6V1G2 (17% vs. 0%) and ATP6V0E 2 (36% vs. 16%). In conclusion, our data indicate that vacuolar H+-ATPase inhibitors are of interest as potential therapeutics for MM.

Bone Morphogenic Protein 6: A Prognostic Factor Expressed by Normal Plasma Cells and Multiple Myeloma Cells Inhibiting Their Proliferation and Angiogenesis Induction

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2701-2701
Author(s):  
Anja Seckinger ◽  
Tobias Meißner ◽  
Jérôme Moreaux ◽  
Hartmut Goldschmidt ◽  
Axel Benner ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Overall Survival ◽  
Cell Lines ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
High Dose Chemotherapy ◽  
High Dose ◽  
Myeloma Cells

Abstract BACKGROUND: Pathogenesis of multiple myeloma is partly attributed to an aberrant expression of proliferation-, pro-angiogenic and bone-metabolism modifying factors by malignant plasma-cells. AIM. Given the long and variable time-span from first diagnosis of early-stage plasma-cell dyscrasias to overt myeloma and the low proliferation rate of malignant plasma-cells, we hypothesize these to concomitantly express a novel class of anti-proliferative factors of potential prognostic relevance. Here, bone morphogenic proteins (BMPs) represent possible candidates, as they inhibit proliferation, stimulate bone formation, and have an impact on the survival of cancer patients. PATIENTS AND METHODS. We assessed expression of BMPs and its receptors by Affymetrix DNA-microarrays (n=434) including CD138-purified primary myeloma-cell-samples, normal bone-marrow plasma-cell-samples, polyclonal plasmoblasts-samples, human myeloma-cell-lines (HMCL), and whole bone-marrow. Presence and differential gene expression was determined by PANP-algorithm and empirical Bayes statistics. Event-free (EFS) and overall survival (OAS) were investigated for the 168 patients undergoing high-dose chemotherapy (HM-group) using Cox’s proportional hazard model. Findings were validated using the same strategy on an independent group of 345 patients from the Arkansas-group. For validation, quantitative real-time PCR and flow cytometry were performed. In vitro induction of angiogenesis was assessed using the AngioKit-assay. Effect of BMP6 on proliferation of HMCL was assessed by 3H-thymidine uptake. RESULTS. BMP6 is the only BMP expressed by normal- (13/14 samples) and malignant plasma-cells (228/233 samples). It is significantly lower expressed in proliferating non-malignant plasmablastic cells and human myeloma cell-lines. In vitro, BMP6 significantly inhibits proliferation of myeloma-cell-lines with an IC50 ranged from 0.08–2.15μg/ml, survival of primary myeloma-cells, and in vitro tubule formation down to the level of the negative control. High BMP6-expression in malignant plasma cells delineates significantly superior overall-survival for patients undergoing high-dose chemotherapy in both independent series of patients (n=168, P=.02 and n=345, P=.03, respectively, see below). CONCLUSION. With BMP6 we report for the first time the autocrine expression of a prognostically relevant anti-angiogenic and anti-proliferative factor and its receptors by normal and malignant plasma-cells. Figure Figure

scholarly journals A novel BCMA/CD3 bispecific T-cell engager for the treatment of multiple myeloma induces selective lysis in vitro and in vivo

Leukemia ◽  
2016 ◽  
Vol 31 (8) ◽  
pp. 1743-1751 ◽  
Author(s):  
S Hipp ◽  
Y-T Tai ◽  
D Blanset ◽  
P Deegen ◽  
J Wahl ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
T Cell ◽  
Plasma Cells ◽  
Ex Vivo ◽  
Xenograft Model ◽  
Selective Lysis ◽  
Bispecific T Cell Engager

Abstract B-cell maturation antigen (BCMA) is a highly plasma cell-selective protein that is expressed on malignant plasma cells of multiple myeloma (MM) patients and therefore is an ideal target for T-cell redirecting therapies. We developed a bispecific T-cell engager (BiTE) targeting BCMA and CD3ɛ (BI 836909) and studied its therapeutic impacts on MM. BI 836909 induced selective lysis of BCMA-positive MM cells, activation of T cells, release of cytokines and T-cell proliferation; whereas BCMA-negative cells were not affected. Activity of BI 836909 was not influenced by the presence of bone marrow stromal cells, soluble BCMA or a proliferation-inducing ligand (APRIL). In ex vivo assays, BI 836909 induced potent autologous MM cell lysis in both, newly diagnosed and relapsed/refractory patient samples. In mouse xenograft studies, BI 836909 induced tumor cell depletion in a subcutaneous NCI-H929 xenograft model and prolonged survival in an orthotopic L-363 xenograft model. In a cynomolgus monkey study, administration of BI 836909 led to depletion of BCMA-positive plasma cells in the bone marrow. Taken together, these results show that BI 836909 is a highly potent and efficacious approach to selectively deplete BCMA-positive MM cells and represents a novel immunotherapeutic for the treatment of MM.

scholarly journals Plasma cells induce apoptosis of pre-B cells by interacting with bone marrow stromal cells

Blood ◽  
1996 ◽  
Vol 87 (8) ◽  
pp. 3375-3383 ◽  
Author(s):  
T Tsujimoto ◽  
IA Lisukov ◽  
N Huang ◽  
MS Mahmoud ◽  
MM Kawano
Keyword(s):  
Bone Marrow ◽  
B Cells ◽  
B Cell ◽  
Cell Survival ◽  
Cell Lines ◽  
Stromal Cells ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Myeloma Cells ◽  
B Cell Survival

By using two-color phenotypic analysis with fluorescein isothiocyanate- anti-CD38 and phycoerythrin-anti-CD19 antibodies, we found that pre-B cells (CD38+CD19+) signifcantly decreased depending on the number of plasma cells (CD38++CD19+) in the bone marrow (BM) in the cases with BM plasmacytosis, such as myelomas and even polyclonal gammopathy. To clarify how plasma cells suppress survival of pre-B cells, we examined the effect of plasma cells on the survival of pre-B cells with or without BM-derived stromal cells in vitro. Pre-B cells alone rapidly entered apoptosis, but interleukin-7 (IL-7), a BM stromal cell line (KM- 102), or culture supernatants of KM-102 cells could support pre-B cell survival. On the other hand, inhibitory factors such as transforming growth factor-beta1 (TGF-beta1) and macrophage inflammatory protein- 1beta (MIP-1beta) could suppress survival of pre-B cells even in the presence of IL-7. Plasma cells alone could not suppress survival of pre- B cells in the presence of IL-7, but coculture of plasma cells with KM- 102 cells or primary BM stromal cells induced apoptosis of pre-B cells. Supernatants of coculture with KM-102 and myeloma cell lines (KMS-5) also could suppress survival of pre-B cells. Furthermore, we examined the expression of IL-7, TGF-beta1, and MIP-1beta mRNA in KM-102 cells and primary stromal cells cocultured with myeloma cell lines (KMS-5). In these cells, IL-7 mRNA was downregulated, but the expression of TGF- beta1 and MIP-1beta mRNA was augmented. Therefore, these results suggest that BM-derived stromal cells attached to plasma (myeloma) cells were modulated to secrete lesser levels of supporting factor (IL- 7) and higher levels of inhibitory factors (TGF-beta1 and MIP-1beta) for pre-B cell survival, which could explain why the increased number of plasma (myeloma) cells induced suppression of pre-B cells in the BM. This phenomenon may represent a feedback loop between pre-B cells and plasma cells via BM stromal cells in the BM.

scholarly journals Primary tumor cells of myeloma patients induce interleukin-6 secretion in long-term bone marrow cultures

Blood ◽  
1994 ◽  
Vol 84 (7) ◽  
pp. 2269-2277 ◽  
Author(s):  
HM Lokhorst ◽  
T Lamme ◽  
M de Smet ◽  
S Klein ◽  
RA de Weger ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Tumor Cells ◽  
Cell Lines ◽  
Plasma Cell ◽  
Plasma Cells ◽  
Adherent Cells ◽  
Myeloma Cells ◽  
Bone Marrow Cultures ◽  
Marrow Cultures

Abstract Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.

scholarly journals Response patterns of purified myeloma cells to hematopoietic growth factors

Blood ◽  
1989 ◽  
Vol 73 (7) ◽  
pp. 1915-1924 ◽  
Author(s):  
KC Anderson ◽  
RM Jones ◽  
C Morimoto ◽  
P Leavitt ◽  
BA Barut
Keyword(s):  
Growth Factors ◽  
Cell Lines ◽  
Plasma Cell ◽  
Plasma Cells ◽  
Interleukin 1 ◽  
Interleukin 2 ◽  
Interleukin 4 ◽  
Hematopoietic Growth Factors ◽  
Myeloma Cells

Abstract Tumor cells were isolated from the bone marrow of seven patients with multiple myeloma and from the peripheral blood of three patients with plasma cell leukemia using Ficoll-Hypaque (FH) density sedimentation followed by immune rosette depletion of T, myeloid, monocytoid, and natural killer (NK) cells. Enrichment to greater than or equal to 93% plasma cells was confirmed with Wright's-Giemsa staining, with intracytoplasmic immunoglobulin staining, and with staining using monoclonal antibodies (MoAbs) directed at B, T, myeloid, monocytoid, and myeloma antigens in indirect immunofluorescence assays. Myeloma cells neither proliferated nor secreted Ig in response to G/M-CSF, G- CSF, M-CSF, interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), or interleukin-4 (IL-4). Significant proliferation (SI greater than or equal to 3.0) was induced by interleukin-6 (IL-6) in six of ten patients (SI of 31 and 43 in two cases); and to interleukin-3 (IL-3) and interleukin-5 (IL-5), independently, in two patients each. Peak proliferation to IL-5 or IL-6 and to IL-3 occurred in cells pulsed with 3[H] thymidine at 24 and 48 hours, respectively; and proliferation to combinations of factors did not exceed that noted to IL-6 alone; Ig secretion was not documented under any culture conditions. Three myeloma-derived cell lines similarly studied demonstrated variable responses. The heterogeneity in the in vitro responses of myeloma cells and derived cell lines to exogenous growth factors enhances our understanding of abnormal plasma cell growth and may yield insight into the pathophysiology of plasma cell dyscrasias.

Plasma Levels of SDF-1 and Expression of SDF-1 Receptor on Multiply Myeloma Cells of Human Multiply Myeloma.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4874-4874
Author(s):  
Caixia Li ◽  
De Pei Wu ◽  
Junjie Cao ◽  
Xiaojin Wu ◽  
Xiao Ma ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Lines ◽  
Plasma Levels ◽  
Myeloma Cell ◽  
Migration Ability ◽  
Myeloma Cells ◽  
And Migration ◽  
Cxcr4 Axis ◽  
Healthy Persons

Abstract Multiple myeloma(MM) is a monoclonal expansion of malignant cells with a plasmablast-plasma cell morphology that is almost exclusively localized to the bone marrow, except at the final stages of disease, when they proliferate in the extramedullary area. The mechanisms of the selective homing of MM cells to the bone marrow compartment are poorly understood. The chemokine stromal cell-derived factor-1 (SDF-1) and its receptor CXCR4 contribute to stem cell homing and play a role in trafficking of leukemic cells. In this study we have investigated expression and biological behavior of SDF-1/CXCR4 in MM-derived cell lines and primary MM cells. FACS and RT-PCR analysis was used to study the expression of CXCR4 and ICAM-1(CD54) on the surface of MM cells from 4 IL-6 dependant cell lines (XG1,XG2,XG6 and XG7) and 25 freshly isolated tumor samples from patients with diagnosed MM. Mononuclear cells were purified by positive selection of magnetical and FACS sorting. Chemotaxis assay through transwell bore polycaronate and ELISA assay were employed to monitor the SDF-1, IL-6, and sICAM-1 levels. We found that[circ1]Fresh MM cells and MM cell lines expressed various levels of functional CXCR4 ranging from 23.1% to 77.7%,which was correlated with the in vitro migration ability of MM cells[(23.2±1.08)%, P<0.01]; [circ2]SDF-1 levels in the bone marrow(BM) of MM patients were significantly higher than the those of healthy persons (3489.23±651.63)pg/ml, (2818.57±597.79)pg/ml, P<0.05; but plasma levels of SDF-1 in peripheral blood of MM patients were lower than those of healthy persons[(1973±133)pg/ml, (2334.857±574.92), P=0.062]; [circ3]Plasma levels of PCL(4097.14±680.71) were significantly higher than those of healthy persons, P<0.01. The results firstly demonstrated abnormal expression of SDF-1 and its receptor CXCR4 on Human MM cells, which is closely correlated with the migration of MM cells. Furthermore, we discovered that SDF-1 could up-regulate the expression of ICAM-1 on MM cells; the plasma level of soluble ICAM-1 was correlated with the expression of CXCR4 on MM cells. These findings suggested that SDF-1/CXCR4 axis play a key role on the trafficking of MM cells via mediating the effect of adhesion molecules. Moreover, we observed higher plasma levels of IL-6 in PB of 60% MM patients compared with those of healthy individuals. Finally, the levels of IL-6 were closely correlated with SDF-1 levels (γ=0.8, P<0.01), These data indicated that in the IL-6-dependent myeloma cell lines or fresh myeloma samples and myeloma cell growth triggered by SDF-1 maybe due to up-regulation of autocrine and paracrine IL-6 by myeloma cells and stromal cells in BM. The results suggested that the expression of CXCR4 have an essential role in the proliferation and migration of myeloma cells in patients with multiple myeloma.In conclusion, MM cells expressed various levels of functional CXCR4, which were correlated with the migration ability of MM cells in vitro; SDF-1/CXCR4 axis plays a key role in the trafficking of MM cells via mediating the effect of adhesion molecules; The plasma levels of IL-6 closely correlated with SDF-1 plasma levels, myeloma cell growth triggered by SDF-1 may be due to up-regulation of autocrine and paracrine IL-6 by myeloma cells and stromal cells in BM. All these suggested that the expression of CXCR4 play an essential role in the proliferation and migration of myeloma cells in patients with multiple myeloma.

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