Collection of peripheral hematopoietic stem/progenitor cells.

OBJECTIVES: Several variables possibly affecting collection of peripheral hematopoietic stem/progenitor cells (PBSC) were evaluated: type of apheresis machine (Amicus version 2.5, Baxter vs Cobe Spectra version 7.0, Terumo BCT), venous access (peripheral vein vs central venous catheter, i.g. CVC), and apheresis regimen (standard vs large volume leukapheresis, i.g. SVL vs LVL) with the objective to increase collection efficacy at the site. BACKGROUND: Peripheral blood represents the currently preferred source of hematopoietic stem/progenitor cells (HSCs) for transplantation. METHODS: Data regarding 169 collection procedures performed in healthy donors and patients between January 2008 and December 2011 at the Clinics of Haematology and Transfusiology in St Cyril and Method Hospital in Bratislava (Slovakia) were analysed. RESULTS: With Cobe Spectra apheresis machine it was possible to process larger blood volumes per procedure with higher CD34+ cell collection efficiency (p = 0.0229) and lower RBC contamination of the harvest than with Amicus (p = 0.0116). On the other hand, Amicus helped to limit PLT contamination of the harvest (p < 0.0001), thus minimizing post-procedural decrease in patient´s PLT count. The highest detected advantage of CVC usage was higher flow rate of procedure, thus processing larger blood volumes per unit of time. Interesting finding was the tendency to lower harvest PLT contamination (p = 0.054). When LVL was performed, significantly higher HSCs yields were collected, even in "poor mobilizers" when the pre-run parameters were low. CONCLUSION: Management of PBSC collection requires a particular approach in each subject. Institutionally and individually optimized collection may help to improve the transplantation outcome and decrease the financial costs (Tab. 8, Ref. 15).

Comparing peripheral blood stem cell collection using the COBE Spectra, Haemonetics MCS+, and Baxter Amicus.

Peripheral blood stem cells (PBSC) have become the most common source of hematopoietic cells for allogeneic or autologous blood and marrow transplantation (BMT). We performed an evaluation of PBSC collections using three different apheresis systems in two major transplantation centers in Singapore. Patients undergoing autologous BMT and donors collecting for allogeneic BMT were harvested using the COBE Spectra, Haemonetics MCS+, or Baxter Amicus. There were 99 Spectra collections (61 were autologous), 81 MCS+ collections (35 were autologous) and 38 Amicus collections (33 were autologous). Our data shows that the Amicus not only processed larger peripheral blood volumes but also yielded larger PBSC volume (P-value<0.05). In terms of PBSC products, the Spectra produced more WBC, WBC/liter blood processed, and WBC/kg (P-value<0.05). The Spectra and MCS+ produced comparable amount of CD34+ cells. Amicus collected 50% less platelets compared to Spectra and MCS+. The total CD34+ cells in the PBSC products was linearly correlated to the circulating CD34+ cells using Spectra, MCS+, and Amicus. Our results suggest that, compared to MCS+ and Amicus, collecting PBSC using the COBE Spectra can produce more WBC with a similar number of CD34+ cells. With a linear correlation of circulating CD34+ cells to the total CD34+ cells in the products, the availability of an automated procedure, no rotating seal, and a small extracorporeal volume, the Spectra appears to be the preferred machine for PBSC collection.

PBPC collections: Management, techniques and risks.

We evaluated the efficiency, safety and risks of three techniques which were used for autologous PBPC collections: (a) large-volume leukapheresis (LVL), (b) standard collections, and (c) a new modified technique which was named as "Mixed" collections. In spite of the fact that the standard and LVL collection techniques are used routinely, there may occur special conditions in which the procedures cannot be recommended. Some patients may suffer from serious clinical complications and they cannot tolerate either standard procedures with administration of higher doses of ACD-A, or the high extent of procedure in the course of LVL. We tried to find the safe and efficient collection technique which could help this group of patients to overcome their problems. The "Mixed" collection technique could be such a choice. The numbers of 136 autologous PBPC collections were performed in 98 patients who suffered from hemato-oncological diseases. We evaluated the results of (a) 93 LVL (more than 3 TBV, total blood volumes of the patients were processed; anticoagulation: ACD-A and Heparin), (b) 16 Standard procedures (less than 3 TBV were processed; anticoagulation: ACD-A), and (c) 27 "Mixed" collections (less than 3 TBV of patients were processed; anticoagulation: ACD-A+ Heparin). Collections were performed by the use of separator Cobe Spectra, Caridian. In patients (a) with a good effect of mobilization (precollection CD 34+ cells in blood higher than 20×10(3)/mL) we prepared almost the same median dose of CD 34+ cells from the standard and "Mixed" collections, 3.8 and 4×10(6)/kg, respectively. In LVL the median yield of CD 34+ cells was 8.2×10(6)/kg. In patients (b) who were mobilized weakly (precollection CD 34+ cells in blood lower than 20×10(3)/mL), LVL enabled to prepare 1.5×10(6) of CD 34+/kg from one collection, while the median yield of CD 34+ cells from the standard and "Mixed" collections was 0.9 and 1.2×10(6)/kg. All the standard, LVL and "Mixed" procedures were tolerated well without any serious adverse reactions. We detected 22 adverse reactions, but only three reactions were associated directly with the procedure. Mild hypocalcemia (2) and hypotensive reaction (1) were transient and treated efficiently. Procedures could continue and were finished according to the planned programme. Other reactions were related either to the insufficient function of central venous catheter or to the poor clinical condition of the patients. LVL enabled to get a higher yield of CD 34+ cells than the Standard and "Mixed" collections in well mobilized patients as well as in weakly mobilized patients. We observed the similar efficiency in standard and "Mixed" collections in well mobilized and weakly mobilized patients. We can recommend LVL in all patients who can tolerate it due to a greater chance of collecting higher yields of progenitor cells. In the weakly mobilized patients LVL offers a greater chance of collecting at least a minimum amount of CD 34+ cells needed for transplantation. "Mixed" collections may be used as an alternative technique under the circumstances in which standard or LVL cannot be recommended - like in patients who do not tolerate a high amount of citrate or a high extent of the procedure, e.g. patients with cardiac arrhytmia, impaired liver or renal function or unstable vital signs.

Isolation of purified autologous peripheral blood CD34+ cells with low T cell content using CliniMACS device--a local experience.

INTRODUCTION: Peripheral blood stem cells (PBSC) mobilised with growth factor with or without chemotherapeutic regimens, are used increasingly in both autologous and allogeneic transplantation. Previously, many PBSC harvests are used directly without ex vivo manipulation, and these PBSC have been shown to be contaminated with tumour cells, which may contribute to subsequent relapses post transplantation. Therefore, requirement for purging of malignant cells from the harvest has initiated the use of various methods to reduce tumour cell contamination of the graft by the positive selection of CD34+ progenitor cells or negative selection of tumour cells using other cell-specific antigens. We report here our local experience with the CliniMACS (magnetic-activated cell separation system) in eight adult patients with haematologic malignancies. OBJECTIVE: To evaluate the purity, recovery and viability of CD34+ cells selected from harvested peripheral blood stem cells using the CliniMACS device, as well as to evaluate the T and B cell contents of these products. METHOD: Eight adult patients with malignant haematological diseases (5 non-Hodgkin's lymphomas in 2nd complete remission (CR) and 3 acute myeloid leukaemias in 1st CR) were mobilised with granulocyte colony-stimulating factor (G-CSF) with or without chemotherapeutic regimens. A total of nine leukaphereses for peripheral blood stem cell harvest using the Cobe Spectra cell separator (Cobe BCT Lakewood, CO) were performed. The harvested PBSC were then positively selected for CD34+ cells using the CliniMACS device (Milteny Biotech, Germany). RESULTS: A total of nine leukapheresis products from eight adults with a median pre-selection total CD34+ cell count of 282.2 x 10(6) (range 103.7 - 738.2 x 10(6)) were positively selected with CliniMACS. The median post-selection total CD34+ cell count was 99.5 x 10(6) (range 7.7 - 443.9 x 10(6)) with the median recovery was 66.0% (range 2 - 94%) and median purity of products of 79% (range 18 - 86%). The median total T cell count was reduced dramatically from 3.1 x 10(9) pre-selection to 7.9 x 10(6) post-selection. The selection did not affect the viability of selected cells that was tested with trypan blue exclusion method with a median pre and post selection viabilities of 98% (range 95 - 98%). CONCLUSION: We conclude that positive selection of CD34+ cells using magnetic separation technology by CliniMACS device results in low T-cell content stem cell with acceptable purity and recovery for autologous peripheral blood stem cell transplantation.

Intramyocardial angiogenic cell precursor injection for cardiomyopathy.

Stem cell therapy for heart failure is a rapidly progressing field. The objective of this study was to assess the safety, and short-term results of thoracoscopic direct injection of angiogenic cell precursors into patients with endstage cardiomyopathy. Cells were obtained from the patient's own blood, avoiding immunological concerns. The number of cells prior to injection was 29.1 +/- 18.9 x10(6). Forty-one patients with cardiomyopathy (mean age, 58.5 +/- 14.3 years) underwent stem cell injection; 21 had dilated cardiomyopathy and 20 had ischemic cardiomyopathy. Overall ejection fraction improved significantly by 4.8% +/- 7.5% at 149 +/- 98 days postoperatively. It increased from 25.9% +/- 8.6% to 28.7% +/- 9.8% in dilated cardiomyopathy, and from 26.6% +/- 5.8% to 33.6% +/- 7.8% in ischemic cardiomyopathy. New York Heart Association functional class was significantly better at 2 months in both groups. It was concluded that thoracoscopic intramyocardial angiogenic cell precursor injection is feasible and safe in patients with cardiomyopathy. The early results are good, and phase II trials are in progress.

Mobilization and collection of peripheral blood progenitor cells for transplantation.

Bone marrow transplantation gradually expanded as a treatment modality for various malignant and non malignant disease conditions. Since the discoveries of the potential of Peripheral Blood Progenitor Cells (PBPC) in the hematopoietic reconstitution mid 1980s and early 1990s PBPC gradually replaced bone marrow as the preferred source of stem cells. The introduction of hematopoietic cytokines that can mobilize large number of progenitors into circulation accelerated PBPC usage. Technological advancements in the apheresis instrumentation greatly helped in the conversion from marrow to PBPC. PBPC collection is less painful, less expensive and transplant with PBPC results in faster hematological recovery than with marrow. Almost all of the autologous transplants are currently performed with PBPC and a similar trend is seen with the allogeneic transplants. The progenitor cell mobilization regimen for autologous patients can be cytokines alone or cytokines combined with chemotherapy. In the majority of the patients the required minimal cell dose of 2.5-5.0 x 10(6)/kg CD34+ cells can be collected in one or two apheresis collections. A few of autologous transplant patients who mobilize poorly require several collections. Allogeneic donors are generally mobilized with daily subcutaneous injections of G-CSF 10 microg/kg for 5 days. The PBPC are collected in one or two apheresis procedures. The side effects of G-CSF are generally mild to moderate; however rare serious reactions including rupture of the spleen have been reported. The collection of PBPC in pediatric patients poses additional challenges yet an adequate dose of cells can be collected with the available apheresis instrumentation. The apheresis collection procedures are safe with no serious adverse consequences. Future scientific advancements may expand the use of PBPC for other clinical application in addition to the current use for hematological reconstitution.

Extremely low frequency magnetic fields originating from equipment used for assisted reproduction, umbilical cord and peripheral blood stem cell transplantation, transfusion, and hemodialysis.

The extremely low-frequency (ELF) magnetic fields (MFs) originating from equipment used for assisted reproduction, umbilical cord-blood and peripheral-blood stem cell transplantation, transfusion, and hemodialysis were measured. The ELF-MF values were 0.1-1.2 microT on clean benches, <0.1-8.0 microT on inverted microscopes, <0.1-13.6 mmicroT in CO2 incubators, 4.3-11.5 microT in centrifuges, 0.4-18.8 microT in programmed freezers, <0.1-0.3 microT in deep freezers, 0.3-3.1 microT on cell separators, and 0.2-0.9 microT in hemodialysers. Frequencies of MFs were nominally 60 Hz, but some devices showed non-sinusoidal 120 Hz. Such MFs can be reduced by shielding the sources or altering the protocols employed.

Performance of a hybrid central venous catheter utilized for both peripheral blood stem cell harvest and transplant support of patients undergoing autologous peripheral blood stem cell transplantation.

Patients undergoing autologous peripheral blood stem cell transplantation (PBSC) frequently require the sequential insertion of two central venous catheters, one for leukapheresis and one for transplant support. Hybrid catheters suitable for leukapheresis and long-term use have been increasingly used, but there is limited information regarding their performance and complication rate. The purpose of this study was to determine the performance of the Pheres-Flow hybrid catheter when utilized for both leukapheresis and transplant support, with particular emphasis on the incidence of infectious and occlusive complications. We prospectively analyzed the performance of 92 catheters in 82 consecutive patients who underwent autologous peripheral blood stem cell (PBSC) transplantation. Occlusion was the most frequent complication of this catheter with 29% of the patients experiencing difficulty drawing blood or infusing fluids. Infection was another frequent complication. Twenty-two percent of patients developed catheter-related bloodstream infections and 15 catheters had to be removed because of proven or suspected infection that did not respond to antibiotic therapy. Nevertheless, 77% of patients were able to complete leukapheresis and transplant support with only one catheter. We conclude that the utilization of the Pheres-Flow catheter for both leukapheresis and transplant support is feasible, but that new strategies need to be developed to decrease the incidence of occlusive and infectious complications of hybrid catheters.