Collection of MNCs and progenitor cells by two separators for PBPC transplantation: a randomized crossover trial

Apheresis collection of mononuclear cells for chimeric-antigen receptor therapies

Collections of lymphocytes to be genetically modified to treat hematologic malignancies have seen a dramatic increase over the last few years as commercial products have been approved. Reports of new products in development that can possibly treat solid organ malignancies represent a massive change in the field. Apheresis is at the center of the collection of cells for the manufacture of these chimeric-antigen receptor therapy products. The expansion of these collections represents one of the areas of apheresis procedures growth. This review will summarize concepts important to this type of collection and variables that need to be optimized to obtain desired cell yields while increasing patients' safety.

Platelet decrease and efficacy of platelet-rich plasma return following peripheral blood stem cell apheresis

BACKGROUND

Peripheral blood stem cell (PBSC) transplantation is a key treatment option for hematological diseases and is widely performed in clinical practice. Platelet loss is one of the major complications of PBSC apheresis, and platelet-rich plasma (PRP) return is considered in case of platelet decrease following apheresis; however, little is known about the frequency and severity of platelet loss and the efficacy of PRP return postapheresis.

METHODS

We assessed changes in platelet counts following PBSC-related apheresis in 270 allogeneic (allo)- and 105 autologous (auto)-PBSC settings. We also evaluated the efficacy of PRP transfusion on platelet recovery postapheresis.

RESULTS

In both allo- and auto-PBSC settings, the preapheresis platelet count (range, 84-385 and 33-558 × 10⁹ /L, respectively) decreased postapheresis (range, 57-292 and 20-429 × 10⁹ /L, respectively), whereas severe platelet decrease (<50 × 10⁹ /L) was only observed in auto-PBSC patients (n = 9). We confirmed that platelet count before apheresis was a risk factor for severe platelet decrease (<50 × 10⁹ /L) following auto-PBSC apheresis (odds ratio 0.749, P < .049). PRP return postapheresis facilitated platelet recovery in more than 80% of cases in both allo and auto settings.

CONCLUSION

Lower platelet count preapheresis is a useful predictor of severe platelet decrease following auto-PBSC apheresis and PRP return is an effective process to facilitate platelet recovery postapheresis.

Comparison of Two Apheresis Systems of COBE and Optia for Autologous Peripheral Blood Stem Cell Collection

Peripheral blood stem cell (PBSC) transplantation following myeloablative therapy is a mainstay of treatment for various types of malignancies. This study aimed to evaluate the differences between the Optia MNC and COBE Spectra MNC systems (Terumo BCT, Japan) according to apheresis procedures and the parameters of apheresis, products, and collection. The clinical data of 74 patients who underwent autologous PBSC collection from July 2012 to July 2015 were reviewed retrospectively. The patients comprised 48 (65%) men and 26 (35%) women with a median age of 56 yr (range, 23–66 yr). Of 216 procedures, 111 (51%) and 105 (49%) were processed by using COBE and Optia MNC, respectively. PBSC collection rates, throughput, numbers of stem cells retrieved, collection efficacy, and platelet loss were compared. There were no significant differences in the median CD34+ cell counts of collected products (0.61×10⁸ vs 0.94×10⁸), CD34 collection efficiency (43.5% vs 42.1%), and loss of platelets (40.1% vs 44.7%). The Spectra Optia MNC apheresis system was comparable to the COBE Spectra system in collecting autologous CD34+ hematopoietic stem cells and retention of platelets.

Prospective randomized and crossover comparison of two apheresis machines for peripheral blood stem cell collection: a multicenter study

BACKGROUND

Improving apheresis technology may lead to an efficient and safe peripheral blood stem cell (PBSC) collection. Recently, the Spectra Optia (Optia, Terumo BCT) was introduced as an automated apheresis instrument, but comparisons with other instruments have been few. This is the first randomized multicenter and crossover comparison of the Optia with the automated program of the established apheresis instrument, the Spectra (Spectra-Auto, Terumo BCT).

STUDY DESIGN AND METHODS

A total of 233 apheresis procedures performed in 46 autologous patients and 108 allogeneic donors were investigated. Apheresis performed in the first day for all subjects using the Spectra-Auto (n = 79) and the Optia (n = 75) were evaluated as first-day analysis. Seventy-nine subjects, who required another session on the second day, underwent apheresis using the other instrument than the first-day instrument and were compared with each other in a paired crossover analysis.

RESULTS

The two instruments processed similar volumes with comparable run times and volumes of acid-citrate-dextrose used. The volumes of collected products were greater in the Optia. Yields of mononuclear cells and CD34+ cells were not different, but collection efficiencies were higher in the Optia (p = 0.008 in CE1 of crossover analysis). Spectra-Auto-collected products contained more contaminating red blood cells (RBCs), whereas there was a trend of more contaminating platelets (PLTs) in the Optia-collected products. Slight reductions were noted in the RBC or PLT counts of subjects who underwent apheresis with the Spectra-Auto or the Optia, respectively.

CONCLUSION

The Optia is safe and more efficient in the PBSC collection compared with the Spectra-Auto.

Hematopoietic stem and progenitor cell harvesting: technical advances and clinical utility

Hematopoietic stem and progenitor cell (HSPC) transplantations require prior harvesting of allogeneic or autologous HSPCs. HSPCs are usually present in bone marrow (BM) during the entire life, in cord blood (CB) at birth, or in peripheral blood (PB) under particular circumstances. HSPCs were first harvested in BM and later in CB and PB, as studies showed interesting features of such grafts. All harvesting methods were in use throughout the years, except BM harvesting for HSPC autologous transplantation, which was replaced by PB harvesting. BM, CB, and PB harvesting methods have been developed, and materials and devices technically improved to increase the number of HSPCs harvested. In parallel, knowing the features of the donors or patients associated with successful numbers of HSPCs allows the adaptation of appropriate harvesting methods. Moreover, it is important to ensure the safety of donors or patients while harvesting. This review describes the methods used for harvesting based on recent studies or developments around these methods, and more particularly, the means developed to increase the numbers of HSPCs harvested in each method. It also explains briefly the influence of technical improvements in HSPC harvesting on potential changes in HSPC graft composition.

Peripheral blood progenitor cell collection by two programs for autologous and allogeneic transplantation

BACKGROUND

In the Spectra apheresis instrument (Terumo BCT), both manual (Spectra-MNC) and automated (Spectra-Auto) programs have been widely used to collect peripheral blood progenitor cells (PBPCs). However, direct comparison of these programs remains extremely limited.

STUDY DESIGN AND METHODS

We investigated 188 collections and products from autologous (patient) and allogeneic (donor) subjects and analyzed a subset of 89 allogeneic collections and products. Twenty-nine subjects who received apheresis for 2 consecutive days using both programs were also evaluated with a paired crossover comparison.

RESULTS

The two programs processed similar volumes, but run time was longer with Spectra-Auto. Yield and efficiency of CD34+ cell collection were similar between these programs in the whole cohort, although white blood cell (WBC) and mononuclear cell (MNC) yields were higher with Spectra-MNC. In the allogeneic cohort, yield and efficiency of WBC collection were greater in Spectra-MNC. However, collected WBCs, MNCs, and CD34+ cells were similar between these programs in paired comparison. Regardless of program, preapheresis peripheral WBC, MNC, and CD34+ cell counts correlated with the number of cells collected. In contrast, preapheresis WBC counts in the whole cohort were negatively correlated with collection efficiencies of CD34+ cells in Spectra-MNC but not Spectra-Auto. The products collected using Spectra-MNC contained more contaminating platelets (PLTs) than Spectra-Auto, with a corresponding reduction in postdonation circulating PLTs.

CONCLUSION

Spectra-MNC and Spectra-Auto showed distinct features that should be considered on a case-by-case basis. Similar investigations should be undertaken as new collection platforms are introduced.

Efficient removal of platelets from peripheral blood progenitor cell products using a novel micro-chip based acoustophoretic platform

Background

Excessive collection of platelets is an unwanted side effect in current centrifugation-based peripheral blood progenitor cell (PBPC) apheresis. We investigated a novel microchip-based acoustophoresis technique, utilizing ultrasonic standing wave forces for the removal of platelets from PBPC products. By applying an acoustic standing wave field onto a continuously flowing cell suspension in a micro channel, cells can be separated from the surrounding media depending on their physical properties.

Study Design and Methods

PBPC samples were obtained from patients (n = 15) and healthy donors (n = 6) and sorted on an acoustophoresis-chip. The acoustic force was set to separate leukocytes from platelets into a target fraction and a waste fraction, respectively. The PBPC samples, the target and the waste fractions were analysed for cell recovery, purity and functionality.

Results

The median separation efficiency of leukocytes to the target fraction was 98% whereas platelets were effectively depleted by 89%. PBPC samples and corresponding target fractions were similar in the percentage of CD34+ hematopoetic progenitor/stem cells as well as leukocyte/lymphocyte subset distributions. Median viability was 98%, 98% and 97% in the PBPC samples, the target and the waste fractions, respectively. Results from hematopoietic progenitor cell assays indicated a preserved colony-forming ability post-sorting. Evaluation of platelet activation by P-selectin (CD62P) expression revealed a significant increase of CD62P+ platelets in the target (19%) and waste fractions (20%), respectively, compared to the PBPC input samples (9%). However, activation was lower when compared to stored blood bank platelet concentrates (48%).

Conclusion

Acoustophoresis can be utilized to efficiently deplete PBPC samples of platelets, whilst preserving the target stem/progenitor cell and leukocyte cell populations, cell viability and progenitor cell colony-forming ability. Acoustophoresis is, thus, an interesting technology to improve current cell processing methods.

CD34+ Cell Enumeration by Flow Cytometry: A Comparison of Systems and Methodologies

Context.—An increasing number of medical centers can collect bone marrow, peripheral blood, or umbilical cord stem cells. Pathology laboratories should accommodate this trend, but investment in additional equipment may be impractical.

Objectives.—To compare CD34+ cell counting results by using 2 widely available flow cytometry systems, with and without the use of a separate hematology analyzer (ie, single-platform versus dual-platform methodologies).

Design.—Whole blood and peripheral blood stem cell (PBSC) samples were analyzed from 13 healthy allogeneic PBSC donors and 46 autologous PBSC donors with various malignancies. The Cytomics FC500 (Beckman Coulter, Fullerton, California) was compared with the FACSCalibur (BD Biosciences, San Jose, California). Dual-platform CD34+ cell counting incorporated data from a KX-21 hematology analyzer (Sysmex, Kobe, Japan).

Results.—Subtle differences in CD34+ cell counting between 2 systems and 2 methods did not achieve statistical significance.

Conclusion.—Different systems and methods for CD34+ cell enumeration, properly validated, can support care for patients undergoing transplants and provide meaningful data for multicenter studies or meta-analyses.

Manual color monitoring to optimize hematopoietic progenitor cell collection on the Fenwal Amicus

A technique was developed to improve consistency of MNC transfers from the centrifuge to the collection bag in the Fenwal Amicus. The operator assures that RBCs completely fill the cassette by the end of the transfer by adjusting the RBC offset in succeeding cycles. We compared yields and crosscellular content before and after implementation of the monitoring technique. Retrospective data from 400 consecutive HPC collection procedures (200 for each technique) were compared. In 40 monitored collections, the RBC offset was adjusted to 6-9 mL to ensure that RBCs completely filled the cassette. Collections requiring these adjustments were not associated with a specific diagnosis. Median values were compared between the 40 collections requiring offset adjustment and those performed before implementation of monitoring. Baseline peripheral CD34+ cell (17 vs. 14 cells μL(-1)), lymphocytes (2 vs. 1.3 × 10(9) /L), WBCs, HCT, and PLTs were significantly higher in the group requiring offset changes. The group requiring offset changes had significantly more CD34+ cells per collection (190.8 × 10(6) or 2.04 × 10(6) /kg vs. 84.3 × 10(6) or 0.89 × 10(6) /kg) and more lymphocytes per collection (16.9 × 10(9) vs. 11.6 × 10(9)). Crosscellular content of the group requiring offset changes was significantly higher for WBCs (41.8 vs. 33.1 × 10(9)), granulocytes (9.6 vs. 7.2 × 10(9)), RBCs (23 vs. 17 mL), and PLTs (2.1 vs. 1.2 × 10(11)). Manual monitoring is a simple, inexpensive method to optimize each HPC collection to maximize CD34+ cell and lymphocyte yields.

Automatic interface-controlled apheresis collection of stem/progenitor cells: results from an autologous donor validation trial of a novel stem cell apheresis device

BACKGROUND

Cryopreserved hematopoietic progenitor cells collected by apheresis from granulocyte-colony-stimulating factor with or without chemotherapy-mobilized patients have become the preferred type of autograft to support treatment of diseases amenable to high-dose chemotherapy. A novel apheresis system, the Spectra Optia v.5.0 (CaridianBCT), was constructed to meet certain shortcomings of manual apheresis systems such as the COBE Spectra MNC (CaridianBCT), including the need for continuous optical or manual monitoring and readjustment of buffy coat position and sensitivity to inconsistent blood flow. By use of optical sensors, which provide real-time automatic interface (buffy coat) and collection line control, the Spectra Optia promises to automatically guide apheresis procedures, potentially freeing up operator time and reducing variability in collection efficiency (CE2).

STUDY DESIGN AND METHODS

In a two-center clinical trial, 35 autologous stem cell donors were subjected to apheresis with the Spectra Optia to validate feasibility and effectiveness of apheresis procedures. Results were compared to data from 80 autologous apheresis procedures with the COBE Spectra MNC.

RESULTS

Usability and function of the automatic interface management were excellent. CD34+ cell quality, assessed by viability staining, colony-forming unit-culture frequency, and engraftment kinetics, was equally good with both systems. CE2 of the Spectra Optia, calculated as CD34+ contents in the product divided by the number of CD34+ cells presented to the collection port, exceeded that of the COBE Spectra MNC. Spectra Optia product volumes were significantly smaller. Very high white blood cell and platelet counts modestly reduced CE2 with the Spectra Optia.

CONCLUSION

The Spectra Optia is a novel automatic apheresis system supporting autologous stem cell collection with at least equal efficiency and superior user-friendliness compared to the COBE Spectra MNC.

Use of various offset settings in the Fenwal Amicus during hematopoietic progenitor cell collection to increase lymphocyte yield and reduce cross-cellular contamination

INTRODUCTION

Autologous HPC collection focus has been CD34+ cell yield but product content of other cells is important for patient survival, complications, and resource utilization.

METHODS

Prospective, paired study examining MNC and RBC offsets (opens and closes collect valve, respectively) was performed using Fenwal Amicus. Lymphocyte, CD34+ cell yields, and cross-cellular contamination were compared using different MNC/RBC offsets and retrospective Spectra data.

RESULTS

In paired comparisons, median lymphocyte yields were significantly different only between 0.0/7.0 (17.6 × 10(9)) and 1.5/5.0 (14.5 × 10(9)) offsets. CD34+ yields were not significantly different between offsets except 1.0/7.0 and 1.5/5.0 (230.3 vs. 156.7 × 10(6)). Granulocytes, RBC, and PLT were significantly greater with higher RBC offset. Comparing all offsets, 1.5/5.0 collected fewer lymphocytes, granulocytes, RBC, and PLT. 1.5/6.0 offsets collected more lymphocytes than 1.5/5.0 but fewer granulocytes and RBC than others except 1.5/5.0. For 1.5/6.0 offsets, PLT content was higher than 1.5/5.0, equivalent to the other offsets, and less than Spectra. CD34+ yields for 1.5/6.0 offsets were equivalent to others except 1.0/7.0. Manufacturer's default (2.3/6.8) collected equivalent lymphocytes and CD34+ to all offsets (except 1.0/7.0) and Spectra. Cross-cellular contamination was higher than 1.5/5.0 and 1.5/6.0 but equivalent to others with more RBC and fewer PLT than Spectra.

CONCLUSION

For maximum lymphocyte yield and minimum contamination, 1.5/6.0 offsets appear optimal. For minimum lymphocyte yield and contamination, 1.5/5.0 offsets would be preferred. Manufacturer's default has CD34+ cell and lymphocyte yields similar to 1.5/6.0 with greater contamination. Amicus can achieve lymphocyte and CD34+ yields similar to Spectra but has significantly less PLT removal.

Automated programs for collection of mononuclear cells and progenitor cells by two separators for peripheral blood progenitor cell transplantation: comparison by a randomized crossover study

BACKGROUND

Although automated programs have been increasingly used to collect peripheral blood (PB) progenitor cells (PBPCs), differences among them remain unclear. The automated programs of Amicus (Baxter Healthcare) and Spectra (software Version 6.1, Gambro BCT) apheresis machines were compared in a crossover study.

STUDY DESIGN AND METHODS

The patients for autologous and donors for allogeneic PBPC transplantation mobilized with granulocyte-colony-stimulating factor were randomly assigned into two groups. PBPCs were collected by the Amicus on the first day and the Spectra on the second of 2 consecutive days in Group I, and the reverse order was used in Group II. Of 39 patients or donors enrolled, 17 reached their collection goal with only one procedure and did not participate in the paired study. Thus, 44 paired procedures of the remaining 22 subjects were evaluated.

RESULTS

The product yields of white blood cells (WBCs; p < 0.005), mononuclear cells (MNCs; p < 0.02), and CD34+ PBPCs (p < 0.0002) from patients or donors were higher in the Amicus collections than those in the Spectra collections. The collection efficiencies of WBCs (p < 0.03), MNCs (p < 0.02), and CD34+ PBPCs (p < 0.03) were higher in the Amicus collections. The numbers of contaminating platelets (PLTs) in the Amicus collections were lower than those in the Spectra collections (p < 0.05) with a greater decrease in PB PLT counts after apheresis with the Spectra (p < 0.01). The Amicus had a longer running time than the Spectra for processing similar volumes (p < 0.005).

CONCLUSION

The automated program of the Amicus may be better than that of the Spectra for collecting MNCs and CD34+ PBPCs and avoiding apheresis-induced thrombocytopenia.

Evaluation of the COM.TEC cell separator in predicting the yield of harvested CD34+ cells

BACKGROUND

This multicenter study was performed with the intention to evaluate the exactness of the predicted CD34+ cell yield calculated by two leukapheresis programs of the cell separator COM.TEC upon the number of donor's circulating CD34+ cells and the blood volume processed.

STUDY DESIGN AND METHODS

Patients and healthy donors (n = 166) received mobilization by chemotherapy and/or granulocyte colony-stimulating factor and underwent CD34+ cell harvest by the leukapheresis programs MNC or RV-PBSC (n = 203).

RESULTS

CD34+ cells were collected by 112 harvests on MNC and by 91 collections on RV-PBSC. The median collection efficiency of CD34+ cells was significantly better for the program MNC than for RV-PBSC (p < 0.001): 67% (31-109) vs. 42% (19-100). The collected CD34+ cell yield was in median more exactly by MNC than by RV-PBSC (p < 0.001): 85% (31-176) vs. 59% (22-110) of the predicted value. Concentrates obtained by RV-PBSC showed in median significantly higher percentages of mononuclear cells (p < 0.001) and CD34+ cells (p < 0.001), 86% (43-99) vs. 56% (25-95) and 1.2% (0.2-14.3) vs. 0.4% (0.1-6.0), and had lower contaminations by erythrocytes (p < 0.001) and platelets (p < 0.001), 13 mL (4-48) vs. 25 mL (5-60) and 1.9 x 1011 vs. 3.1 x 1011, than those harvested by MNC.

CONCLUSION

The significantly better collection efficiency of CD34+ cells and the more exact prediction of the harvested CD34+ cell yield make the leukapheresis program MNC a safe and efficient procedure. However, concentrates collected by RV-PBSC are of a better cellular quality with a significantly higher percentage of mononuclear and CD34+ cells and a lower contamination by erythrocytes and platelets.

Comparison of the Fenwal Amicus and Fresenius Com.Tec cell separators for autologous peripheral blood progenitor cell collection

Peripheral blood progenitor cells (PBPC) are commonly used as a stem cell source for autologous transplantation. This study was undertaken to evaluate blood cell separators with respect to separation results and content of the harvest. Forty autologous PBPC collections in patients with hematological malignancies were performed with either the Amicus or the COM.TEC cell separators. The median product volume was lower with the Amicus compared to the COM.TEC (125 mL vs. 300 mL; p < 0.001). There was no statistically significant difference in the median number of CD34+ cell/kg in product between the Amicus and the COM.TEC (3.0 x 10(6) vs. 4.1 x 10(6); p = 0.129). There was a statistically higher mean volume of ACD used in collections on the Amicus compared to the COM.TEC (1040 +/- 241 mL vs. 868 +/- 176 mL; p = 0.019). There was a statistical difference in platelet (PLT) contamination of the products between the Amicus and the COM.TEC (0.3 x 10(11) vs. 1.1 x 10(11); p < 0.001). The median % decrease in PB PLT count was statistically higher in the COM.TEC compared to the Amicus instruments (18.5% vs. 9.5%; p = 0.028). In conclusion, both instruments collected PBPCs efficiently. However, Amicus has the advantage of lower PLT contamination in the product, and less decrease in PB platelet count with lower product volume in autologous setting.

Apheresis products of the Amicus™ and the AS.TEC 204® cell separators are comparable with regard to dendritic cells derived from the mononuclear cell collection

BACKGROUND

In this study, we investigated the quality of autologous mononuclear cells (MNC) collected with two different cell separators using standard MNC-apheresis procedure modalities. MNCs were purified by density gradient centrifugation and cultured according to standard protocols to generate dendritic cells (DC) and 1 x 10(7)/ml immature DCs were pulsed with tumour lysate for 3 days and subsequently characterized by fluorescent-activated cell sorter analysis.

RESULTS

No difference was found in the monocyte content of either apheresis product (P = 0.07) and in the overall yield of MNCs (P = 0.7). Mature DCs as defined by their phenotype revealed also no significant difference: Amicus, 118 x 10(6) cells +/- 91 vs. AS.TEC 204, 128 x 10(6) cells +/- 137 (P = 0.55), respectively, although the contamination with platelets (threefold) and red cells (twofold) was significantly higher in the AS.TEC 204 group (P < 0.05) than in the Amicus group.

CONCLUSION

The Amicus and the AS.TEC 204 are equally capable in providing MNCs for the generation of DCs and the amount of concomitantly collected red cells and platelets had no impact on the final DC yield.

Prospective randomised comparison of the COBE Spectra version 6 and Haemonetics MCS+ cell separators for hematopoietic progenitor cells leucapheresis in patients with multiple myeloma

A randomised crossover trial of two separators was undertaken to compare the mononuclear cell, CD34(+) cell and CFU-GM yield, in patients (<61 years) with previously untreated symptomatic multiple myeloma. After first-line therapy, all patients received mobilising chemotherapy (cyclophosphamide 4 g/m(2)) and daily G-CSF. The first leucapheresis was performed on the first day the peripheral blood absolute CD34(+) cell count was > 20 cells/microl. All patients underwent 2 leucaphereses on consecutive days. The patients were randomised to undergo either the first or second leucapheresis using the COBE Spectra. The target duration of the procedure on the COBE Spectra was 2 total blood volumes, and for the Haemonetics MCS(+) it was 20 cycles with four recirculations. Between September 2003 and March 2005, 60 patients were entered in the study. COBE Spectra version 6 processed significantly larger volumes of blood than the Haemonetics MCS(+) (8,845 and 5,680 ml, respectively, P < 0.01). The absolute yield of mononuclear cells (2.1 vs. 1.5 x 10(8)/kg, P = 0.04), CFU-GM (11 vs. 3 x 10(4)/kg, P = 0.01) and CD34(+) cells (3 vs. 1.7 x 10(6)/kg, P = 0.02) were all significantly higher with the COBE Spectra version 6, as were the yields per unit volume of blood processed. In conclusion, our study shows that COBE Spectra Version 6 is faster and has a better yield than the Haemonetics MCS(+), in patients with multiple myeloma.

Apheresis techniques for collection of peripheral blood progenitor cells

The combination of effective mobilisation protocols and efficient use of apheresis machines has caused peripheral blood progenitor cells (PBPC) transplantation to grow rapidly. The development of apheresis technology has improved over the years. Today PBSC procedures have changed towards systems to minimise operator interaction and to reduce the collection of undesired cells such as polymorphonuclear cells and platelets using functionally closed, sterile environments for PBSC collection in keeping with Good Manufacturing Practice guidelines. Blood cell separators with continuous flow technique allow the processing of more blood than intermittent flow devices resulting in higher PBSC yields. Large volume leukapheresis with the processing of 3-4-fold donor's/patient's blood volume can increase the number of collected progenitor cells. Therefore, intermittent flow cell separators are indicated if only single vein access is available. Anticoagulant induced hypocalcaemia is an often observed side effect in long lasting PBPC harvesting and monitoring of electrolytes should be performed especially at the end of the apheresis procedure to supplement low levels of potassium, calcium or magnesium. Refinement and improvement of collection techniques continue to add to the armamentarium of current approaches for cancer and non-malignant conditions and will enable future strategies.

Recommendations for optimized settings of the Amicus Crescendo cell separator for the collection of CD34+ progenitor cells

BACKGROUND

CD34+ PBPCs for autologous transplantation purposes are collected by leukapheresis procedures on automated cell separators. In this study, the influence of different parameters on collection efficiency (CE) of the Amicus Crescendo cell separator (Baxter) was investigated.

STUDY DESIGN AND METHODS

A total of 146 PBPC collections with Amicus cell separators were performed in 56 patients with either settings recommended by the manufacturer or modified settings to identify variables that have a significant and important impact on CE.

RESULTS

By use of a standard setting with a cycle volume of 1400 mL, CE significantly decreases when patients' preapheresis peripheral blood WBC counts are between 25,000 and 35,000 per micro L. CE can be improved if cycle volume is reduced to 1000 mL. If WBC concentrations exceed 55,000 per micro L before apheresis, CE also significantly decreases despite of reduced cycle volume. Additionally, high flow rates greater than 60 mL per minute significantly reduce CE.

CONCLUSION

Parameters influencing the outcome of CD34+ PBPC collections were identified, such as patients' WBC count, cycle volume, and whole blood flow rate. An optimized adjustment of these variables will further increase the CE of the device.

Collection of peripheral progenitor cells: a comparison between Amicus and Cobe-Spectra blood cell separators

The authors compared the efficiency of two different blood cell separators (Amicus and Cobe-Spectra) in collecting peripheral blood progenitor cells for autologous or homologous transplantation. A total number of 129 procedures were performed, 36 with Spectra, 93 with Amicus. There was no difference between Spectra and Amicus efficiencies for CD34+ cell collection (46.685% vs 46.235%; p=n.s) but the platelet efficiencies were 17.31% and 12.54% respectively (p=0.04) and, if autologous and allogeneic collections were considered separately, a marked difference resulted in allogeneic platelet efficiency between 6 Spectra and 23 Amicus procedures (26.83% vs 8.68%, p=0.0004). The authors were able to demonstrate that in 70 Amicus autologous collections there was a different platelet efficiency, if peripheral count was considered: 12 procedures performed with a platelet count > 100 x 10(9)/l had a very low efficiency (6.86%), but this value increased if platelet count lowered (13.02% if between 100 and 50 x 10(9)/l, 22.63% if between 50 and 0 x 10(9)/l, 23 and 35 procedures respectively). The study is preliminary and the number of collections is little, but the overall data suggest that Spectra (AutoPBSC, V 6.0) and Amicus separators have the same efficiency for collecting CD34+ cells while Amicus procedures have a very low platelet contamination, especially with donors.