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)

Selection of CD34+ hematopoietic progenitor cells from autografts may be performed in multiple myeloma (MM) to minimize contamination with tumor cells. This approach is based on the assumption that the malignant cells do not express the CD34 antigen. Therefore, we first compared the CD34+/CD10+ and CD34+/CD19+ subpopulations from bone marrow (BM) and peripheral blood (PB) of fourteen MM patients and five normal controls. No difference between the respective early B cell subsets of both groups could be observed. Using tricolor flow cytometry, the CD19 expression on CD34+/CD10+ cells in BM was found to increase continuously from CD19- to CD19dim. In contrast, circulating CD34+/CD10+ cells did not coexpress the CD19 antigen. This population may contain myeloid progenitor cells or bipotential progenitor cells of the myeloid and lymphoid lineage as suggested by data obtained with fetal liver cells. Further functional studies are required. Enrichment of CD34+ cells with immunomagnetic beads was performed from BM of three MM patients and four normal donors. The CD34+ cells were selected with the HPCA-1 antibody and detached from the beads with chymopapain. Compared with the starting cell preparation, a 3.97 +/- 0.48 log (mean +/- SE) reduction of plasma cells could be achieved after CD34 selection. On morphological examination, 84% +/- 4% of the cells in the CD34+ fraction (MM) were immature blasts. The plating efficiency for hematopoietic colony forming cells was 9.7% +/- 2.8% in the CD34 selected fraction of the MM group, reflecting a 51-fold increase as compared with the starting population.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:CD34 selection for purging in multiple myeloma and analysis of CD34+ B cell precursors. 751 57

Recently, high-dose chemo- and radiotherapy for newly diagnosed young patients with multiple myeloma has been established in member centers of the Nordic Myeloma Study Group (NMSG). The treatment includes supportive use of autologous hematopoietic blood progenitors harvested by leukapheresis. Safe and adequate hematopoietic support with minimal toxicity requires optimization of the number and quality of harvested progenitors. We have therefore established a workshop consisting of the 11 laboratories within the NMSG with the aim of developing recommendations for enumeration of CD34-positive cells. In this first workshop report, we discuss technical variables affecting the enumeration of progenitors harvested by leukapheresis and make specific recommendations. The products are analyzed within 4 h following erythrocyte lysis using the Ortho lysing solution for 8-10 minutes. A sample containing 0.5-1.0 x 10(6) nucleated cells is incubated with the test or control antibody (anti-CD34 = HPCA-2PE and Ms IgG1PE from Becton Dickinson) at dilutions of 1:10 to 1:40 in a final volume of 1 ml. The samples are incubated 15 minutes at ambient temperature, washed two to three times, and fixed with 1% paraformaldehyde (150 microliters/pellet) for a minimum of 10 minutes. Flow cytometric analysis is performed on 50,000 cellular events with debris eliminated. The estimation of CD34-positive cells can be performed on an FL2-side-scatter plot after marking of a positive population containing > 50 events. Using quadrant statistics, this population can be identified in the upper left quadrant, among cells with the side-scatter profile of small lymphocytic cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Report from a Nordic workshop on CD34+ cell analysis: technical recommendations for progenitor cell enumeration in leukapheresis from multiple myeloma patients. Nordic Myeloma Study Group Laboratories. 753 62

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

Three different methods for determination of CD34+ cells in G-CSF-mobilized peripheral blood were compared. The methods were: the Milan/Mulhouse protocol, the ISHAGE guidelines for CD34+ cells enumeration and our own protocol. The procedure we have adopted is essentially a Milan/Mulhouse protocol-derived methodology combined with a multiparametric approach using the PAINT-A-GATE software analysis program. The samples were collected from 70 patients affected by acute leukemia, non-Hodgkin's lymphoma, Hodgkin's lymphoma, myeloma and breast cancer who were scheduled to receive autologous PBSC transplantation. PBSC collection was performed following mobilization with subcutaneous G-CSF at 5-10 microg/kg/day. A minimum target of 2 x 10(6)/kg CD34+ cells was considered an acceptable harvest to ensure a safe transplant. On average, three aphereses per patient were performed and a total of 204 apheresis samples were analyzed. Regression analysis of the percentage and absolute number of CD34+ cells, as calculated with each method, achieved an excellent correlation in spite of methodological differences. In fact, both CD34+dim and CD34+CD45- events were included in our gating strategy. In the setting of a triple staining associating CD34, CD38 and CD45, we identified a variable fraction of CD34+CD38+CD45- cells which would be otherwise undetected due to its CD45 negativity. To this end, we used a new technology referred to as laser-scanning cytometry (LSC) which allowed the isolation and morphological identification of CD34+CD45- cells. By comparing CD34+CD45+ and CD34+CD45- cells, we found that they share a common morphology, thus confirming the hypothesis that the latter are to be considered for CD34+ cell calculation. The median number of CD34+ cells/kg, as calculated by the three methods, was: 4.79 x 10(6)/kg (range 1-570) for the Milan/Mulhouse protocol, 3.9 x 10(6)/kg (range 0.8-498) for the ISHAGE one, and 5.17 x 10(6)/kg (range 2-599) for our protocol. The median time to ANC and PLT engraftment was 11 (range 9-24) and 20 (range 10-70) days, respectively. Our protocol achieved the best correlation between CD34+ cells/kg and time to ANC/PLT recovery according to the Spearman's rank test (r = -40 and P < 0. 015 for ANC, r= -46 and P = 0.005 for PLT). We conclude that (1) CD45 does not appear the ideal partner of HPCA-2 for determination of hematopoietic progenitors in mobilized peripheral blood; and (2) for clinical application, a single staining with 8G12 appears simple, reliable and feasible when rigorous procedures for sample preparation and acquisition are followed and an adequate software for multiparametric analysis is available.
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PMID:Enumeration of CD34+ hematopoietic progenitor cells for clinical transplantation: comparison of three different methods. 1055 63