Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously described a sensitive and specific CD34 enumeration assay and report here a prospective analysis of 25 myeloma patients undergoing PBSC mobilization using this assay to determine the optimal days for collection of CD34+ and CD34+Thy-1+ cells after chemotherapy and growth factor mobilization. Correlations between frequency of peripheral blood CD34+ cells, circulating white blood cell (WBC) count, apheresis CD34+ cell count, nucleated cell count (NCC), and numbers of apheresis colony-forming units granulocyte/macrophage (CFU-GM) were determined. To assess levels of the more primitive subsets of CD34+ cells in the PBSC collections, coexpression of the Thy-1 antigen (CDw90) on CD34+ cells was also assessed. Marked heterogeneity was noted between patients with apheresis samples containing a median NCC of 4.2 x 10(8)/kg (range 1.3-8.1), median CFU-GM 17 x 10(4)/kg (range 0.15-32 x 10(4)/kg), and median CD34+ cell count of 1.39 x 10(6)/kg (range 0.02-6.6). The frequency of CD34+ cells in PBSC collections coexpressing Thy-1 was also heterogenous (6.2-50% of CD34+ cells), median 21.6%, mean 24.7 +/- 2%. The apheresis CD34+ cell count correlated with the peripheral blood CD34+ cell percentage (r = 0.71, p < 0.0001) but only weakly with the peripheral WBC. Apheresis CD34+Thy-1+ cell numbers correlated strongly with the circulating CD34+ cell numbers (r = 0.80), but no correlation was noted between these candidate stem cells and the peripheral WBC. In contrast, apheresis CFU-GM levels correlated most strongly with the peripheral WBC count (r = 0.61, p < 0.0001). The apheresis CD34+ cell count correlated with apheresis CFU-GM (r = 0.75, p < 0.0001) but not with the apheresis NCC. Apheresis CD34+Thy-1+ counts significantly correlated only with the apheresis CD34+ cell count and not with the apheresis CFU-GM or NCC. A higher percentage of circulating and apheresis CD34+ cells expressing Thy-1 were found on day 1 of collection, and the percentage of CD34+ cells expressing Thy-1 decreased on each subsequent day of measurement: median of 22% day 1 vs. 16.6% day 4, p = 0.04. This study therefore confirms that accurate quantitation of circulating CD34+ cells best predicts the optimal day for apheresis collection of CD34+ and CD34+Thy-1+ cells and is superior to the WBC count in this regard. Furthermore, the candidate stem cell (CD34+Thy-1+) subset is most prevalent during the earliest phases of CD34+ cell mobilization.
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PMID:Optimizing the CD34+ and CD34+Thy-1+ stem cell content of peripheral blood collections. 854 56

Peripheral blood progenitor cells are being used increasingly as part of the treatment protocol for a variety of haematological malignancies. The most appropriate mobilisation therapy and the optimum collection procedures have yet to be fully elucidated. 28 patients with myeloma (9), NHL (11) and HD (8) underwent PBSC mobilisation and harvesting between November 1992 and October 1993. Two protocols were used; the myeloma group received high-dose cyclophosphamide, 7 g/m2 + G-CSF and were leucapheresed on 5 consecutive days during the recovery period using the Haemonetics V50 and the lymphoma group a lower dose of cyclophosphamide, 3 g/m2 + G-CSF followed by leucapheresis on 2 or 3 occasions using a Cobe Spectra. Median time to achieve a WBC of 1 x 10(9)/l during the recovery phase, was 14 days (11-16) and 10 days (9-15) respectively. Median numbers of MNC and CFU-GM collected for the myeloma group were 5.9 x 10(8)/kg (2.5-13.5) and 69.4 x 10(4)/kg (9.9-268.1) and for the lymphoma group. 5.1 x 10(8)/kg (1.2-11.1) and 35.4 x 10(4)/kg (1.2-129.7). Three patients with lymphoma had a low yield of CFU-GM, two of which did not proceed to autograft. The third patient failed to engraft and died despite receiving bone marrow backup. For the remaining 25 patients, median time to neuts > 0.5 x 10(9)/l and platelets > 50 x 10(9)/l was 9 (8-13) and 11 (9-23) days for the myeloma group and 12 (9-15) and 13 (9-180) days for the lymphomas. We found a strong correlation between CD34+ cells and CFU-GM from the last 9 patients. There is a correlation between CFU-GM infused and speed of engraftment. All patients who received > 10 x 10(4) CFU-GM/kg showed a rapid engraftment for neutrophils and platelets. In all cases, when > 4 x 10(8)/kg MNC were harvested, > 10 x 10(4) CFU-GM/kg were obtained. Sufficient cells for a rapid engraftment can be obtained from 2 leucaphereses in the majority of patients. The recovering peripheral blood WBC provides a good indicator of when to harvest. The target value of CFU-GM can be predicted by the number of cells harvested and by the number of CD34 positive cells in the leucapheresis product.
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PMID:Peripheral blood progenitor cell harvesting in multiple myeloma and malignant lymphoma. 859 Aug 50

Malignant cells in haemopoietic autografts can contribute to post-transplant relapse. Engraftment of myeloma patients with CD34+ peripheral blood progenitors selected from total autografts reduces the number of tumour cells infused by 2.7-4.5 logs. Residual tumour cells detected in CD34+ selected cells may be due to selection impurity or the existence of malignant CD34+ progenitors. In three patients we evaluated the CD34 purity and tumour load of total autografts, CD34+ progenitors selected with immunomagnetic beads and highly purified CD34+ progenitors obtained in two rounds of selection (combining magnetic with flow cytometry activated cell sorting) to determine the cause of residual tumour cells in CD34 selections. Using allele-specific oligonucleotides (ASO) complementary to the unique Ig heavy chain sequence (CDRIII region) of the malignant clone, semi-quantitative ASO-PCR was capable of detecting one malignant cell in 10(4)-10(5) normal white blood cells. Selection of CD34+ cells from bone marrow (BM) with approximately 20% malignant plasma cells resulted in a 1.4 log reduction of tumour burden. Using two-colour flow-cytometry we observed CD34-, BB4+ malignant plasma cells contaminating this CD34 selection. Prior to sorting, peripheral blood cell autografts (PBCA) contained approximately 0.1% malignant cells. Selection of > 99% pure CD34+ cells using immunomagnetic beads (Dynal) resulted in an approximate 2 log reduction of malignant cells, but residual tumour cells were still detectable. ASO-PCR detected no malignant cells in > 99.9% pure CD34+ peripheral blood progenitors obtained with two rounds of selection (combining magnetic with flow cytometry activated cell sorting). We conclude that CD34+ malignant cells are not detectable in myeloma PBCA and that residual tumour cells in CD34 selections are due to contaminating CD34-negative cells.
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PMID:CD34 selections from myeloma peripheral blood cell autografts contain residual tumour cells due to impurity, not to CD34+ myeloma cells. 865 82

Aneuploidy and lg light chain restriction were used as separate, independent tumor specific markers to study 26 patients with multiple myeloma to determine whether bone marrow B cells, as defined by CD19 expression, are clonally related to myeloma plasma cells. Specimens were characterized using multidimensional flow cytometry to identify the presence of clonality in both the B lymphoid and plasma cell populations using both surface and cytoplasmic staining with antibodies specific for kappa or lambda lg light chain In none of the patients with multiple myeloma were CD19+ cells found to be clonally restricted to kappa or lambda. The monoclonal plasma cells (MPC) were found to be uniformly negative for CD10, CD19, and CD34, while the CD19+ B lymphoid cells present within the samples expressed normal intensities and relationships of these antigens, which allowed them to serve as internal positive controls. Combined analysis of call surface antigen expression and DNA content allowed plasma cell populations to be characterized for aneuploidy without interference from normal bone marrow cells. The MPC, detected on the basis of bright CD38 expression (CD38+2), demonstrated DNA aneuploidy in 65% of cases (DNA index range of 0.9 to 1.3). These aneuploid DNA distributions had typical cell cycle profiles (including G1,S and G2+M) expected of a proliferating population. In all cases, DNA aneuploidy was confined almost entirely to the CD38+2, CD19- malignant plasma cells, while cells expressing CD19 were diploid. These results support the concept that myeloma is a disease process mediated by self-replicating, late compartments of B-cell ontogeny.
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PMID:Tumor-specific aneuploidy not detected in CD19+ B-lymphoid cells from myeloma patients in a multidimensional flow cytometric analysis. 869 10

Peripheral blood is increasingly used instead of bone marrow as a source of hemopoietic precursor cells for transplantation. The optimal technique still needs to be defined. Selection of CD34+ cells in transplant material may be of benefit in allogeneic and autologous peripheral blood precursor cell transplantation (PBPCT), since it allows elimination of unwanted CD34-negative cells, such as T-cells and contaminating tumor cells. We have evaluated the feasibility of CD34 selection in PB transplants and studied hemopoietic reconstitution after autologous transplantation of CD34 selected precursor cells. Between August 1994 and June 1995 CD34 selection was performed on 12 transplants for 9 patients with malignant disease (non-Hodgkin lymphoma [n = 5]; Ewing sarcoma [n = 1]; chronic lymphocytic leukemia [n = 1]; breast cancer [n = 1]; multiple myeloma [n = 1]). PBPC were collected with a Fenwall CS 3000 harvester after stimulation with G-CSF. For selection of CD34+ cells the Ceprate LC34 system (CellPro) was used. A median CD34 purity of 73% (range 40-94%) was achieved. The median number of CD34 positive cells per transplant was 4.8 x 10(6)/kg body weight (range 0.7-15.8). The median number of colony forming cells per transplant was 31 x 10(4)/kg body weight (range 1.5-131.3). For autologous PBPCT the minimal number of CD34 positive cells required in the transplantate was arbitrarily set at 1.0 x 10(6)/kg body weight. This number was achieved in 10 of the 12 transplants. The median loss of CD34+ cells during selection was 1.5 x 10(6)/kg body weight (range 0.2-6.4). In 2 patients the total number was reduced to below the critical value of 1.0 x 10(6)/kg. 7 of the 9 patients received the CD34 selected transplant after intensive chemotherapy and irradiation. The median follow-up time after PBPCT was 196 days (range 62-278). All 7 patients are now alive and with normal hemopoietic function. A granulocyte count above 0.5 x 10(9)/l and a platelet count above 20 x 10(9)/l was achieved on day 14 (median), and on day 19 after PBPCT. We conclude that CD34 selection is technically feasible and that CD34 selected cells can be used for PBPCT. The procedure is time consuming and expensive; it requires complex organization at laboratory level, and the benefit of CD34 selection with regard to T-cell depletion and tumor purging still needs to be proven. However, CD34+ selection is likely to open new perspectives in transplantation medicine.
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PMID:[Autologous transplantation of hematopoietic precursor cells following CD34 selection]. 872 Jul 23

The methods of mobilization and collection of stem cells in peripheral blood stem cells transplantation (PBSCT) and the association between the number of stem cells transplanted and hematopoietic recovery were studied. The investigation was carried in 22 patients (11 acute leukemia, 6 multiple myeloma, 4 non-Hodgkin's lymphoma, 1 breast cancer). Three regimens for mobilization were carried out as follows: 1) chemotherapy + tetrahydrofolic acid + dexamethasone, 2) chemotherapy + rhGM-CSF + dexamethasone, 3) chemotherapy + rhG-CSF + dexamethasone. Besides, CD34/CD33 dual-color direct immunofluorescence flow cytometry assay was performed in 7 cases in the rhG-CSF group. The results showed: 1) The mean number of collected cells (MNC) in the rhG-CSF group was MNC (8.29 +/- 6.14) x 10(8)/kg and CFU-GM (21.35 +/- 17.24) x 10(4)/kg, being highest among the 3 groups. 2) The number of CD34+ cells correlated with MNC and CFU-GM. CD34+ cells in the peripheral blood were 0 or < 0.5% before mobilization and increased markedly 6-8 days after rhG-CSF administration. Harvesting should be started at that time and carried out every day until CD34+ cells reached 5 x 10(6)/kg. 3) The number of PBSC transplanted was the key to hematopoietic recovery.
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PMID:[A study on the peripheral blood stem cells mobilization, collection and their effects on engraftment]. 873 24

We have performed nine CD34 selection procedures on peripheral blood stem cells harvested from eight patients with myeloma using the Cellpro avidin-biotin immunoaffinity column (Ceprate). They all received CVAMP chemotherapy to maximum response prior to mobilisation. Six of the patients have been transplanted using these cells, one receiving successive autografts. Median absolute cell numbers processed and retrieved were: 31.1 x 10(9) pre-column, 2.07 x 10(8) in the final product and 30.4 x 10(9) in the column waste. Mean CD34 positivity in the product was 49% (range 18.4-98) with a median CD34+ yield of 31.4% (range 21-37.8). IgH PCR was performed and seven of the eight patients were amplifiable. Of these, two were positive in the pre-column product and both of these were successfully purged with a negative result in the final, post-column product. Patients were transplanted with a median of 2.0 x 10(6) CD34+ cells/kg (range 1.5-9.4) following conditioning with melphalan 200 mg/m2. The mean time to recovery of neutrophils to > 0.5 x 10(9)/l and platelets to > 20 x 10(9)/l was 16 and 17 days, respectively. At a mean follow-up of 9 months, four of the six patients transplanted are alive, three of them in complete remission and one in a clinically stable relapse. One has died of disease relapse and one of progressive neurological problems the aetiology of which was uncertain but there was no sign of progression of their myeloma. We conclude that PBSCT using CD34 selected cells is safe and practical in myeloma following remission induction with CVAMP chemotherapy.
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PMID:Peripheral blood stem cell transplantation in myeloma using CD34 selected cells. 873 88

We developed a new monoclonal antibody. B-B4, which specifically identifies human plasma cells. It strongly reacts with all multiple myeloma cell lines and with malignant plasma cells of all tumour samples of the multiple myeloma patients tested. B-B4 does not react with any peripheral blood, bone marrow or tonsil cells. Cloning of the B-B4 antigen reveals that the monoclonal antibody recognizes syndecan-1. It appears that the monoclonal antibody B-B4 is a suitable marker for human plasmocyte identification among haemopoietic cells and a useful probe for the diagnosis of haematological malignancies. Furthermore, this monoclonal antibody can be used for depletions prior to CD34 grafting.
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PMID:A plasmocyte selective monoclonal antibody (B-B4) recognizes syndecan-1. 935 31

Whether or not peripheral stem cells have an unlimited capacity for self renewal is debated. However, everyday haematopoietic requirements are met by progenitors; and it seems that few "real' stem cells are needed. Although we may not yet have identified these "true' stem cells, for practical purposes the long term culture-initiating cells (LTC-ICs) are a close approximation. To date, experience in peripheral blood progenitor cell (PBPC) transplantation is largely confined to non-ablative regimens. It is therefore difficult to determine the number of PBPCs needed to effect long-term reconstitution. The number of tumour cells present among mobilised PBPCs can be reduced using the CD34 affinity column and by positive purging methods. The ex vivo expansion of CD34 cells also has the effect of diluting tumour cell concentration. In clinical use, PBPC transplantation has a proven role in support of high dose chemotherapy in certain haematological and oncological malignancies but the concept of dose intensification is not universally accepted. With the exception of leukaemia, lymphoma, myeloma or relapsed testicular cancer and possibly some subgroups of breast cancer; high dose chemotherapy does not demonstrate a survival benefit. For patients with CML, autografting with Ph- cells appears to become a useful alternative to allogeneic BMT. Allogeneic PBPC transplantation may have potential, though work is preliminary. Cord blood transplantation between matched siblings is viable, but it is not yet clear whether this source will increase the donor pool for adults needing allogeneic transplantation. For gene therapy using haematopoietic cells to be effective, a greatly increased rate of transduction will be needed. Meeting in Paris in September 1995, a European School of Oncology Task Force considered a number of important questions relating to peripheral blood progenitor cell (PBPC) physiology and transplantation. This review is a brief account of their conclusions.
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PMID:Peripheral blood progenitor cell transplantation: where do we stand? Chairman's Summary of the European School of Oncology Task Force meeting Peripheral Blood progenitor cell's held September 29-30, 1995. 880 40

Recently, Nordic protocols have been activated for the use of high-dose chemotherapy and radiotherapy to treat newly diagnosed young patients with multiple myeloma, breast cancer, and malignant lymphomas. The protocols include transplantation of autologous stem cells or progenitors as supportive therapy. This requires a safe number and optimal quality of the harvested cells. Consequently, the Nordic stem cell laboratories established a collaboration to optimize enumeration of CD34+ cells by flow cytometry. In the first workshop (WS-I) report, we addressed the issue of standardization of technical variables. Taking into consideration the variations in estimation of progenitors, a safe graft should contain > 2.0 x 10(6) CD34+ cells per kilogram patient weight, harvested by two or three leukaphereses. This report presents the results from the second workshop (WS-II). Twelve blood or leukapheresis products were shipped and analyzed in 24 stem cell laboratories, and all results were returned to a central database at Herlev Hospital, Copenhagen. The data documented a significant correlation between CD34+ cell enumerations of the 12 samples analyzed in each of the 24 different stem cell laboratories within the Nordic stem cell laboratory group (NSCL-G). At a practical workshop, the NSCL-G developed a standard for the performance of CD34 enumeration. This is based on the simple Milan Protocol, which uses the anti-HPCA-2PE marking of CD34+ (FL-2) nongranulated (lowSSC) cells. The NSCL-G has decided to hold a third workshop (WS-III) to establish working recommendations for double marking of CD34+ lineage-specific subsets and for handling cellular material for storage of RNA and DNA from blood and leukapheresis products.
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PMID:Nordic flow cytometry standards for CD34+ cell enumeration in blood and leukapheresis products: report from the second Nordic Workshop. Nordic Stem Cell Laboratory Group (NSCL-G). 881 90


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