Evaluation of 'out-of-specification' CliniMACS CD34-selection procedures of hematopoietic progenitor cell-apheresis products.

BACKGROUND: Immunomagnetic selection of CD34(+) hematopoietic progenitor cells (HPC) using CliniMACS CD34 selection technology is widely used to provide high-purity HPC grafts. However, the number of nucleated cells and CD34+ cells recommended by the manufacturer for processing in a single procedure or with 1 vial of CD34 reagent is limited. METHODS: In this retrospective evaluation of 643 CliniMACS CD34-selection procedures, we validated the capacity of CliniMACS tubing sets and CD34 reagent. Endpoints of this study were the recovery and purity of CD34+ cells, T-cell depletion efficiency and recovery of colony-forming units-granulocyte-macrophage (CFU-GM). RESULTS: Overloading normal or large-scale tubing sets with excess numbers of total nucleated cells, without exceeding the maximum number of CD34+ cells, had no significant effect on the recovery and purity of CD34+ cells. In contrast, overloading normal or large-scale tubing sets with excess numbers of CD34+ cells resulted in a significantly lower recovery of CD34+ cells. Furthermore, the separation capacity of 1 vial of CD34 reagent could be increased safely from 600 x 10(6) CD34+ cells to 1000 x 10(6) CD34+ cells with similar recovery of CD34(+) cells. Finally, T-cell depletion efficiency and the fraction of CD34+ cells that formed CFU-GM colonies were not affected by out-of-specification procedures. DISCUSSION: Our validated increase of the capacity of CliniMACS tubing sets and CD34 reagent will reduce the number of selection procedures and thereby processing time for large HPC products. In addition, it results in a significant cost reduction for these procedures.

Cost analysis and quality of life assessment comparing patients undergoing autologous peripheral blood stem cell transplantation or autologous bone marrow transplantation for refractory or relapsed non-Hodgkin's lymphoma or Hodgkin's disease. a prospective randomised trial.

The cost-effectiveness of autologous peripheral blood stem cell transplantation (PBSCT) compared with autologous bone marrow transplantation (ABMT) for refractory or relapsed non-Hodgkin's lymphoma (NHL) or Morbus Hodgkin (MH) was assessed. Costs were determined from the induction chemotherapy regimen up to 3 months after discharge from hospital following the transplantation. Quality of life was measured by the EuroQol, the Rotterdam Symptom Checklist (RSCL) and the SF-36. Patients were randomised according to a 2:1 ratio to undergo either PBSCT or ABMT. 62 patients underwent PBSCT and 29 ABMT. Costs of the transplantation period were significantly lower in the PBSCT group (15008 Euros) than in the ABMT group (19000 Euros). Significant differences in quality of life were all in favour of PBSCT and emerged using the RSCL, both on 14 days after the transplantation and three months after discharge. We conclude that PBSCT is associated with lower costs and a better quality of life than ABMT for patients with refractory or relapsed NHL or MH.

Autologous peripheral blood stem cell transplantation in patients with relapsed lymphoma results in accelerated haematopoietic reconstitution, improved quality of life and cost reduction compared with bone marrow transplantation: the Hovon 22 study.

The present study analysed whether autologous peripheral blood stem cell transplantation (PSCT) improves engraftment, quality of life and cost-effectiveness when compared with autologous bone marrow transplantation (ABMT). Relapsing progressive lymphoma patients (n = 204; non-Hodgkin's lymphoma n = 166; Hodgkin's disease n = 38) were, after induction treatment with the DHAP-VIM (cisplatin, cytarabine, dexamethasone, etoposide, ifosfamide, methotrexate) regimen, randomly (2:1) assigned to the harvest of granulocyte-macrophage colony-stimulating factor-mobilized stem cells after the second DHAP course or autologous bone marrow cells before the second DHAP course. These stem cells were reinfused following high-dose myeloblative chemotherapy. After induction, 118 patients obtained a partial or complete response and were eligible for randomization. In the PSCT arm (n = 76) significantly faster engraftment of neutrophils [> or = 0.1 and > or = 0.5 x 10(9)/l: 10.7 d (7-36, median, range), 15 (9-45) versus 13 (8-25) and 26 (14-80), P < 0.01] and thrombocytes [> or = 20 x 10(9)/l: 13 d (7-51) versus 18 (11-65), P < 0.01] were observed. In addition, significantly fewer transfusions of red blood cells [6 (0-23) versus 8 (2-24), P < 0.01] and platelets [4 (0-60) versus 8 (2-55), P = 0.01] were required in the PSCT arm. These findings were associated with a significant reduction in the median days of intravenous antibiotics in patients with fever [8.5 (0-30) versus 14 (0-34), P = 0.04] and hospital stay [27 (8-51) versus 34 (24-78), P < 0.05]. Quality of life demonstrated a significant difference in favour of the PSCT arm. Total transplantation costs were significantly lower in the PSCT arm [$13,954 ($4913- 29,532) versus $17 668 ($10,170-44,083) P < 0.05], as a result of the reduced hospital stay and lower antibiotic costs. In summary, these results indicate that PSCT is superior to ABMT with regard to engraftment, supportive care, quality of life and cost.

Assessment of telomere length in hematopoietic interphase cells using in situ hybridization and digital fluorescence microscopy.

Telomeres are G/C-rich repetitive DNA sequences at the end of all eukaryotic chromosomes. The loss of telomeric repeat sequences during cell divisions has been proposed as a possible mechanism for cell senescence. The standard procedure for measurement of telomere length is Southern blot (SB) hybridization with a telomere-specific probe. However, in using this technique no information can be obtained on variation in telomeric fragments due to interchromosomal, intrachromosomal, and intercellular differences. Lansdorp et al. (Hum Mol Genet 5:685-691, 1996) developed a method to measure individual telomeres, using in situ hybridization on metaphase chromosomes, employing peptide nucleic acid (PNA) probes and digital fluorescence microscopy. In this paper we describe a method that can be used to assess telomeric length in interphase cells. An algorithm was developed to measure the total intranuclear fluorescence in situ hybridization (FISH) signal, which features accurate correction for the local autofluorescence. Application of this methodology to samples of fetal liver, umbilical cord blood, and adult bone marrow cells showed a gradual decrease of average telomeric length. Southern blot analysis and PNA FISH measurements on chromosomes in the same samples showed similar results. Advantages of interphase measurements include the possibility of studying nonproliferating cells, thus avoiding selection and cell culturing.