Infection of apheresis cells by parvovirus B19. (1/271)

Parvovirus B19 is the only member of the Parvoviridae family known to cause disease in humans. Owing to the high level of cell tropism the virus can only replicate in proliferating and differentiating erythroid precursor cells, which are present in human bone marrow and foetal liver. As human bone marrow is very difficult to obtain, an alternative in vitro system for the propagation of B19 virus has been developed, based on the application of mobilized haemapoietic progenitor (apheresis) cells. These cells are routinely harvested from cancer patients after treatment with recombinant human granulocyte/macrophage colony-stimulating factor. Replication of parvovirus B19 in vitro is possible in these cells after stimulation with erythropoietin. Therefore, this system is an easily, accessible alternative to the use of human bone marrow in parvovirus B19 infection assays.  (+info)

CD34+ cell enumeration in peripheral blood and apheresis samples, using two laboratory diagnostic kits or an institutional protocol. (2/271)

In order to prepare the substitution of a commercially available diagnostic kit, ProCOUNT (Becton Dickinson) or Stem-Kit (Coulter Immunotech), for our institutional protocol, we compared the three techniques for the numeration of CD34+ progenitor cells in 50 peripheral blood and 51 apheresis samples, obtained from cancer patients or healthy donors. We show here that the three techniques yield results of the same order of magnitude. Although statistical analyses demonstrate significant differences between the three methods, these differences turned out to be clinically insignificant in most situations. Observed differences mostly affect samples with the highest content of CD34+ cells, while the three assays provide equivalent results for values that are close to clinically relevant thresholds (20 x 10(3) CD34+ cells/ml in peripheral blood to start apheresis, and accumulated number above 3 x 10(6) CD34+ cells/kg to stop apheresis). This study also supports the view that institutional protocols can provide a highly reliable determination of CD34+ cells counts and percentages. However, because institutional protocols often use research reagents and vary from institution to institution, the use of diagnostic kits may be prefered as one way to improve quality assurance in the practice of cell therapy.  (+info)

Superior autologous blood stem cell mobilization from dose-intensive cyclophosphamide, etoposide, cisplatin plus G-CSF than from less intensive chemotherapy regimens. (3/271)

The study purpose was to determine if G-CSF plus dose-intensive cyclophosphamide 5.25 g/m2, etoposide 1.05 g/m2 and cisplatin 105 mg/m2 (DICEP) results in superior autologous blood stem cell mobilization (BSCM) than less intensive chemotherapy. From January 1993 until May 1997, 152 consecutive patients with non-Hodgkin's lymphoma (n = 55), breast cancer (n = 47), Hodgkin's disease (n = 14), multiple myeloma (n = 9), AML (n = 9), or other cancers (n = 18) initially underwent BSCM by one of three methods: Group 1: G-CSF alone x 4 days (n = 30). Group 2: disease-oriented chemotherapy, dosed to avoid blood transfusions, followed by G-CSF starting day 7 or 8, and apheresis day 13 or 14 (n = 82). Group 3: DICEP days 1-3, G-CSF starting day 14, and apheresis planned day 19, 20 or 21 (n = 40). A multivariate analysis was performed to determine which factors independently predicted BSCM. The median peripheral blood CD34+ (PB CD34+) cell count the morning of apheresis linearly correlated with the number of CD34+ cells removed per litre of apheresis that day. The median PB CD34+ cell count and median CD34+ cells x 10(6) removed per litre of apheresis were highest for Group 3, intermediate for Group 2, and lowest for Group 1. By multivariate analysis, mobilization group (3 > 2 > 1), disease other than AML, no prior melphalan or mitomycin-C, and less than two prior chemotherapy regimens predicted better BSCM. Out of 15 Group 3 patients who had infiltrated marrows, 11 had no detectable cancer in marrow and apheresis products after DICEP. These data suggest that DICEP results in superior BSCM than less intensive chemotherapy regimens.  (+info)

Image-guided central venous catheters for apheresis. (4/271)

Apheresis is an increasingly important procedure in the treatment of a variety of conditions, sometimes performed via peripheral access because of concern over major complications associated with central venous catheter (CVC) placement. This study sought to determine the safety and success for ultrasound and fluoroscopically guided, non-tunneled dual lumen CVCs placed for apheresis. Prospective data collection was made of 200 attempted CVC placements in the radiology department utilizing real time sonographic guidance. The complications relating to placement were noted in all and the number of passes required for venepuncture and whether a single wall puncture was achieved was recorded in 185 cases. Duration of catheterization and reason for line removal were recorded in all. Our study group included 71 donors providing peripheral blood stem cells for allogeneic transplant. CVCs were successfully placed in all patients, 191 lines in the internal jugular and seven in the femoral vein. 86.5% required only a single pass and 80.5% with only anterior wall puncture. Inadvertent but clinically insignificant arterial puncture occurred in six (3%) cases. In no case did this prevent line placement. There were no other procedure-related complications. 173 (87.4%) catheters were removed the same day. No catheters were removed prematurely. There was one case of prolonged venous bleeding. Our study demonstrates the safety of central venous catheters for apheresis provided that duration of catheterization is short and real-time sonographic guidance is used for the puncture, and guide wire and catheter placement are confirmed fluoroscopically.  (+info)

Recombinant human thrombopoietin in combination with granulocyte colony-stimulating factor enhances mobilization of peripheral blood progenitor cells, increases peripheral blood platelet concentration, and accelerates hematopoietic recovery following high-dose chemotherapy. (5/271)

Lineage-specific growth factors mobilize peripheral blood progenitor cells (PBPC) and accelerate hematopoietic recovery after high-dose chemotherapy. Recombinant human thrombopoietin (rhTPO) may further increase the progenitor-cell content and regenerating potential of PBPC products. We evaluated the safety and activity of rhTPO as a PBPC mobilizer in combination with granulocyte colony-stimulating factor (G-CSF) in 29 breast cancer patients treated with high-dose chemotherapy followed by PBPC reinfusion. Initially, patients received escalating single doses of rhTPO intravenously (IV) at 0.6, 1.2, or 2.4 micrograms/kg, on day 1. Subsequent patients received rhTPO 0.6 or 0.3 micrograms/kg on days -3, -1, and 1, or 0.6 micrograms/kg on days -1 and 1. G-CSF, 5 micrograms/kg IV or subcutaneously (SC) twice daily, was started on day 3 and continued through aphereses. Twenty comparable, concurrently and identically treated patients (who were eligible and would have been treated on protocol but for the lack of study opening) mobilized with G-CSF alone served as comparisons. CD34(+) cell yields were substantially higher with the first apheresis following rhTPO and G-CSF versus G-CSF alone: 4.1 x 10(6)/kg (range, 1.3 to 17.6) versus 0.8 x 10(6)/ kg (range, 0.3 to 4.2), P =.0003. The targeted minimum yield of 3 x 10(6) CD34(+) cells/kg was procured following a single apheresis procedure in 61% of the rhTPO and G-CSF-mobilized group versus 10% of G-CSF-mobilized patients (P =.001). In rhTPO and G-CSF mobilized patients, granulocyte (day 8 v 9, P =.0001) and platelet recovery (day 9 v 10, P =.07) were accelerated, and fewer erythrocyte (3 v 4, P =.02) and platelet (4 v 5, P =.02) transfusions were needed compared with G-CSF-mobilized patients. Peripheral blood platelet counts, following rhTPO and G-CSF, were increased by greater than 100% and the platelet content of PBPC products by 60% to 110% on the first and second days of aphereses (P <.0001) with the greatest effect seen with repeated dosing of rhTPO at 0.6 microgram/kg. rhTPO is safe and well tolerated as a mobilizing agent before PBPC collection. Mobilization with rhTPO and G-CSF, in comparison to a comparable, nonrandomized G-CSF-mobilized group of patients, decreases the number of apheresis procedures required, may accelerate hematopoietic recovery, and may reduce the number of transfusions required following high-dose chemotherapy for breast cancer.  (+info)

Potential role for hyaluronan and the hyaluronan receptor RHAMM in mobilization and trafficking of hematopoietic progenitor cells. (6/271)

Although the mechanism(s) underlying mobilization of hematopoietic progenitor cells (HPCs) is unknown, detachment from the bone marrow (BM) microenvironment and motility are likely to play a role. This work analyzes the motile behavior of HPCs and the receptors involved. CD34(+)45(lo/med)Scatterlo/med HPCs from granulocyte colony-stimulating factor (G-CSF)-mobilized blood and mobilized BM were compared with steady-state BM for their ability to bind hyaluronan (HA), their expression of the HA receptors RHAMM and CD44, and their motogenic behavior. Although RHAMM and CD44 are expressed by mobilized blood HPCs, function blocking monoclonal antibodies (MoAbs) identified RHAMM as a major HA binding receptor, with a less consistent participation by CD44. Permeabilization of mobilized blood HPCs showed a pool of intracellular (ic) RHAMM and a smaller pool of icCD44. In contrast, steady-state BM HPCs have significantly larger pools of icRHAMM and icCD44. Also, in contrast to mobilized blood HPCs, for steady-state BM HPCs, MoAbs to RHAMM and CD44 act as agonists to upregulate HA binding. The comparison between mobilized and steady-state BM HPCs suggests that G-CSF mobilization is associated with depletion of intracellular stores of HA receptors and modulates HA receptor usage. To confirm that mobilization alters the HA receptor distribution and usage by HPCs, samples of BM were collected at the peak of G-CSF mobilization in parallel with mobilized blood samples. HA receptor distribution of mobilized BM HPCs was closely matched with mobilized blood HPCs and different from steady-state BM HPCs. Mobilized BM HPCs had lower pools of icHA receptors, similar to those of mobilized blood HPCs. Treatment of mobilized BM HPCs with anti-RHAMM MoAb decreased HA binding, in contrast to steady-state BM HPCs. Thus, G-CSF mobilization may stimulate an autocrine stimulatory loop for HPCs in which HA interacts with basal levels of RHAMM and/or CD44 to stimulate receptor recycling. Consistent with this, treatment of HPCs with azide, nystatin, or cytochalasin B increased HA binding, implicating an energy-dependent process involving lipid rafts and the cytoskeleton. Of the sorted HPCs, 66% were adherent and 27% were motile on fibronectin plus HA. HPC adherence was inhibited by MoAbs to beta1 integrin and CD44, but not to RHAMM, whereas HPC motility was inhibited by MoAb to RHAMM and beta1 integrin, but not to CD44. This finding suggests that RHAMM and CD44 play reciprocal roles in adhesion and motility by HPCs. The G-CSF-associated alterations in RHAMM distribution and the RHAMM-dependent motility of HPCs suggest a potential role for HA and RHAMM in trafficking of HPCs and the possible use of HA as a mobilizing agent in vivo.  (+info)

Autoaggression syndrome resembling acute graft-versus-host disease grade IV after autologous peripheral blood stem cell transplantation for breast cancer. (7/271)

Acute graft-versus-host disease (aGVHD) after autologous progenitor cell transplantation has been associated with blood transfusion or cyclosporine. Mild aGVHD grades I-II, identified as autoaggression or engraftment syndrome, has recently been described in autologous progenitor transplantation. Here, we report the first case of pathologically documented grade IV aGVHD after autologous peripheral blood progenitor cell transplantation in a patient with breast cancer. The allogeneic origin was excluded by molecular techniques, and no cyclosporine or cytokines were administered.  (+info)

Enrichment of peripheral blood CD34+ cells for transplantation using a fully automated immunomagnetic cell selection system and a novel octapeptide releasing agent. (8/271)

Positive selection of CD34+ cells is being increasingly performed to support hematological reconstitution following high-dose and dose-intensive chemotherapy and to reduce the non-target cell content of transplants. The present study was designed to evaluate the performance of an immunomagnetic cell selection system, including comparison of enzyme and peptide releasing agents and of semi-automated and fully automated selection systems. A total of 74 immunomagnetic CD34+ cell selection procedures were performed involving 55 subjects, the majority of whom had hematologic malignancies. Median CD34+ cell purity with a newly developed specific octapeptide releasing agent (98.5%; 81.0-99.0%) was significantly higher (P = 0.002) than that with chymopapain (85.8%; 28.1-99.7%). No significant differences were observed between semi-automated and fully automated systems in CD34+ cell purity or yield or time to WBC or platelet recovery. Immunomagnetic selection was found to provide highly purified populations of CD34+ cells in sufficient numbers for use in transplantation procedures. CD34+ cell transplants supported rapid and reliable hematologic reconstitution. Use of a fully automated system markedly reduced the time and labor required for immunomagnetic selection, potentially affording more standardized and reproducible positive selection of CD34+ cells.  (+info)

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