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.     

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.     

Collection of peripheral blood mononuclear cells as a byproduct of plateletpheresis with two different blood cell separators

Peripheral blood mononuclear cells (PBMC) were collected as a byproduct of plateletpheresis of normal blood cell donors using modifications to standard automated protocols on either the CS-3000 or Spectra blood cell separator machine. Comparison of the PBMC products obtained showed X ± SD WBC yields of 5.3 ± 3.4 vs. 3.8 ± 2.0 × 10⁹ with the CS-3000 and Spectra, respectively (P < .0001). The majority of the cells were lymphocytes, with 13–15% monocytes with both machines. Sixteen percent of the WBC collected with the Spectra, but only 1% of those collected with the CS-3000, were granulocytes. The CS-3000 PBMC product contained fewer RBC (0.2 ± 0.1 × 10¹¹ vs. 2.4 ± 0.6 × 10¹¹) and more platelets (1.6 ± 0.6 × 10¹¹ vs. 0.35 ± 0.39 × 10¹¹) in a smaller volume (40 ± 14 ml vs. 229 ± 37 ml) than the Spectra products. Comparison of the platelet collections harvested when PBMC were also collected to platelets harvested using standard procedures on the same machine showed no change in platelet. WBC, or RBC yields for the Spectra. A significant increase in mean WBC contamination from 40 ± 56 × 10⁷ to 112 ± 205 × 10⁷ and a small, but statistically insignificant, decrease in platelet yield from 4.1 ± 1.2 × 10¹¹ to 3.9 ± 1.8 × 10¹¹ was observed in the CS-3000 platelet collections when PBMC were harvested. There was no sustained change in donor lymphocyte counts and no change in acute donor side effects or time requirements when PBMC were collected. The procedural modifications were easily learned by multiple operators, and required about 15 and 5 min additional operator time on the CS-3000 and Spectra, respectively. Thus, harvest of large numbers of PBMC as a byproduct of plateletpheresis can be readily accomplished with either of 2 different blood cell separator machines. The cells obtained have been useful for a variety of purposes in both clinical hospital and basic research laboratories. © 1992 Wiley-Liss, Inc.     

两种血细胞分离机干/祖细胞采集和移植效果的比较

背景:外周血造血干/祖细胞通过血细胞分离机进行体外收集,血细胞分离机的性能、工作状况将直接关系到采集物的特性和数量,从而直接影响受者的造血重建.目的:比较Fenwal CS-3000 Plus与Amicus两种血细胞分离机采集外周血造血干/祖细胞及受者移植效果.方法:共入选接受异基因外周血干细胞移植患者51例,Fenwal CS-3000 Plus组27例,平均年龄(34.2±10.6)岁;Amicus组24例,平均年龄(35.4±12.1)岁.比较两组采集物有核细胞数、CD34+细胞数、采集效率、红细胞与血小板采集量及造血重建时间.结果与结论:两组采集物的有核细胞数、CD34+细胞数、采集效率、红细胞采集量及造血重建时间差异均无显著性意义;Fenwal CS-3000Plus组血小板采集量明显高于Amicus组(P<0.01).结果显示Fenwal CS-3000 Plus与Amicus血细胞分离机在分离外周血干/祖细胞方面和移植效果没有差异;血小板较低被采集者使用Amicus血细胞分离机采集可能更为安全.     

两种血细胞分离机干/祖细胞采集和移植效果的比较

背景：外周血造血干/祖细胞通过血细胞分离机进行体外收集,血细胞分离机的性能、工作状况将直接关系到采集物的特性和数量,从而直接影响受者的造血重建。目的：比较Fenwal CS-3000Plus与Amicus两种血细胞分离机采集外周血造血干/祖细胞及受者移植效果。方法：共入选接受异基因外周血干细胞移植患者51例,Fenwal CS-3000Plus组27例,平均年龄（34.2±10.6）岁;Amicus组24例,平均年龄（35.4±12.1）岁。比较两组采集物有核细胞数、CD34＋细胞数、采集效率、红细胞与血小板采集量及造血重建时间。结果与结论：两组采集物的有核细胞数、CD34＋细胞数、采集效率、红细胞采集量及造血重建时间差异均无显著性意义;Fenwal CS-3000Plus组血小板采集量明显高于Amicus组（P〈0.01）。结果显示Fenwal CS-3000Plus与Amicus血细胞分离机在分离外周血干/祖细胞方面和移植效果没有差异;血小板较低被采集者使用Amicus血细胞分离机采集可能更为安全。     

Platelet collection with the Amicus and the AS.TEC 204 blood cell separators

BACKGROUND: Platelet collection with two new blood cell separators was compared with respect to platelet yield, separation efficiency, white cell (WBC) contamination, and measures of component quality. Both machines offer a menu for the collection of a desired platelet yield. The harvesting of a definite platelet yield is a means of collecting a standardized therapeutic platelet dose. STUDY DESIGN AND METHODS: One hundred seventy-two platelet collections were carried out with different protocols in the two devices (Amicus and AS.TEC 204). For that reason, healthy donors underwent plateletpheresis procedures using the continuous- and discontinuous-flow systems. Separations with a definite endpoint volume and the option of collecting a desired platelet yield of 5.5 × 10(11) in the Amicus and 3.3 × 10(11) in the AS.TEC 204 machine were investigated. RESULTS: With the Amicus blood cell separator, platelet yield (5.02+/−0.46 × 10[11]) and separation efficiency (66.9+/−6.2%) were significantly higher than those with the AS.TEC 204 (3.02+/−0.62 × 10[11] and 46.4+/−6.7%, respectively). There was less deviation between the platelet yield and the desired platelet yield in the AS.TEC 204 machine than in the Amicus device. WBC contamination was 2.06+/−2.91 × 10(6) in components obtained from the AS.TEC 204 machine, and 87.5 percent of the platelet concentrates had a WBC content <5 × 10(6). None of the components from the Amicus device contained more than 5 × 10(6) WBCs. Except for platelet morphology score, measures of component quality were almost equal in the platelet concentrates obtained from the studied machines. CONCLUSION: Platelet yield and separation efficiency were significantly higher in the Amicus blood cell separator. The collection of a desired platelet yield was better achieved with the AS.TEC 204 device.     

Collection of peripheral blood progenitor cells: analysis of factors predicting the yields.

We retrospectively analyzed data on 628 leukapheresis from 160 consecutive patients with hematologic or solid malignancies to identify predictive factors affecting the achievement of optimal peripheral blood progenitor cell (PBPC) collection, which was defined as > or = 5x10(6) CD34+ cells/kg. In univariate analysis, a diagnosis of multiple myeloma, no prior axial skeletal radiotherapy, absence of exposure to alkylating agents and cisplatin, fewer cycles of chemotherapy, and fewer number of previous chemotherapy regimens favored the achievement of target number of PBPC. In multivariate analysis, the absence of prior exposure to alkylating agents, especially cyclophosphamide, (P=0.003, RR=2.08) and cisplatin (P=0.015, RR=2.50) were independent predicting factors affecting the probability of achieving the target PBPC and the time to reach the target PBPC collection. In addition, the total dose of cyclophosphamide the patient received significantly alters the mobilization.     

Collection of platelets and peripheral progenitor cells with the Fresenius AS.TEC 204 blood cell separator

The aim of the present study was to clinically evaluate the blood cell separator AS. TEC 204. One hundred fifteen platelet collections were carried out with the dual or single needle procedure. Platelet yield was 3.21 ± 0.80 × 10¹¹ (mean ± standard deviation) and 59.1% of the collections showed platelet counts >3.0 × 10¹¹. Leukocyte contamination was 1.77 ± 2.81 × 10⁶ and 89.0% of the platelet concentrates had a white blood cell content <5 × 10⁶. Using a dual needle technique with an alternating interface adjustment, all of the products were contaminated with less than 1 × 10⁶ leukocytes. Furthermore, 23 peripheral progenitor cell collections were performed in 12 patients and three allogeneic donors. Median numbers of harvested CD 34 antigen expressing cells/kg body weight were 0.78 (range 0–4.7) and 3.67 × 10⁶ (range 2.2–5.23), respectively. We conclude that platelet and progenitor cell collections can be carried out with efficient results. The collections were well tolerated by the donors. J. Clin. Apheresis 12:126–129, 1997. © 1997 Wiley-Liss, Inc.     

Collection of peripheral blood progenitor cells with an automated leukapheresis system

BACKGROUND: Apheresis devices designed for the collection of mature blood elements are being used for the collection of peripheral blood progenitor cells (PBPCs).The collection of PBPCs differs from that of other cells in the rarity of the target cell and in the fact that donors may undergo several days of collection. A consequence of this process may be a depletion of blood cells such as platelets from the blood. The disposable set and operating software for an apheresis device (Spectra, COBE BCT) was modified by the manufacturer to automate the collection of PBPCs and reduce the collection of unwanted blood cells. STUDY DESIGN AND METHODS: A study was initiated to compare the collection of PBPCs with the new device, the AutoPBSC (version [V]6.0 with AutoPBSC tubing set), and that with the MNC (mononuclear cell) procedure (V4.7 with white cell tubing set), for patients and healthy donors. RESULTS: Patients whose blood was processed by either theV6.0 orV4.7 procedure achieved the target dose of 5 x 10(6) CD34+ cells per kg of patient weight in similar numbers of procedures, even though the calculated collection efficiency for CD34+ cells using the automated V6.0 procedure was significantly less than that with the V4.7 procedure for both allogeneic donors and patients donating PBPCs. The collection efficiency for platelets was lower with the V6.0 procedure, and components collected in this manner contained fewer platelets. Apheresis by the V6.0 procedure required 30 to 60 more minutes per procedure than apheresis by the V4.7 procedure. Review of engraftment kinetics after transplantation did not reveal any effect of the collection procedure on recipients of either allogeneic or autologous transplants. CONCLUSION: The collection efficiencies of the V6.0 procedure for both CD34+ cells and mature blood cells are lower than those of the V4.7 procedure.The lower collection efficiency for platelets results in a smaller drop in peripheral blood platelet count after the procedure.The automated features of the V6.0 procedure may simplify PBPC collection, but this procedure requires a longer apheresis.     

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

BACKGROUND: Efficient collection of progenitor cells is essential for PBPC transplantation. Two apheresis machines (Amicus, Baxter Healthcare; and Spectra, Gambro BCT, software version 4.7) were compared prospectively by a crossover trial. STUDY DESIGN AND METHODS: Apheresis collections were performed for two consecutive days on patients for autologous and donors for allogeneic PBPC transplantation. The patients and donors, receiving a G-CSF, were randomized into two groups. In Group I, PBPCs were collected by the Amicus on the 1st day and the Spectra on the 2nd day, and the reverse order was used with Group II. A total of 60 apheresis procedures of 30 (16 in Group I and 14 in Group II) among 40 patients and donors enrolled were performed and evaluated. RESULTS: The nucleated cell counts, MNC counts, CD34+ PBPC counts, and amounts of CFU-GM collected per procedure were similar with the Amicus and the Spectra. On the other hand, the decrease of peripheral blood platelet counts of patients and donors was more prominent from using Spectra than Amicus (p < 0.0001). Components collected by the Amicus had fewer platelets than those collected by the Spectra (p < 0.0001). The efficiencies of collecting nucleated cells, MNCs, and CD34+ PBPCs were not different between the machines (p > 0.05). However, the efficiency of collecting platelets was significantly higher with Spectra than with Amicus (p < 0.0001). The Amicus took longer than the Spectra to process the same volume (p < 0.05). CONCLUSION: Amicus is superior to Spectra in avoiding apheresis-induced thrombocytopenia caused by platelets contaminating the collected samples. Therefore, the Amicus is useful for patients with thrombocytopenia or with a less-than-normal platelet count.     

White cell reduction during plateletpheresis: a comparison of three blood cell separators

BACKGROUND: White cell (WBC)-reduced single-donor platelet concentrates (SDPs) can be collected by the newest generation of blood cell separators. Three WBC-reduction techniques during plateletpheresis were investigated in the present study with respect to WBC content and platelet yield. STUDY DESIGN AND METHODS: The Amicus device used the elutriation principle for WBC reduction, and separations with periodically alternating interface position (PAIP) were employed in the AS.TEC 204. WBC reduction by in-line filtration was performed in the MCS+. Platelets were measured electronically and WBCs were determined manually (Nageotte chamber). RESULTS: In-line filtered SDPs showed significantly lower WBC content (0.088+/-0.178 x 10(6)) than SDPs that were WBC reduced by elutriation (0.31+/-0.48 x 106) or PAIP technique (0.89+/-1.57 x 10(6), p = 0.0001). Platelet yield (5.0+/-0.46 x 10(11)) was significantly higher in components obtained with the Amicus device (p = 0.0001). The AS.TEC 204 and MCS+ gave similar results for platelet yields: 3.15+/-0.63 and 3.28+/-0.71 x 10(11), respectively. CONCLUSIONS: The plateletpheresis systems studied allow the collection of WBC-reduced SDPs. In-line filtration resulted in the best WBC reduction. Some SDPs collected with the devices studied had a WBC content >1 x 10(6) per unit. Platelet yield was significantly higher in SDPs from the Amicus device.     

Comparison of CD34+ cell collection on the CS-3000+ and Amicus blood cell separators

BACKGROUND: Mobilized PBPCs, detectable on the basis of CD34 expression, can be collected on various cell separators. The CD34+ cell collection efficiencies of two cell separators (CS-3000+ and Amicus, Baxter) were tested on two comparable groups of oncology patients. STUDY DESIGN AND METHODS: Leukapheresis assisted by the standard manufacturer's software and variables settings was performed in 37 (CS-3000+) and 34 (Amicus) patients (total of 83 and 67 collections, respectively) after chemotherapy plus G-CSF treatment. RESULTS: The total CD34+ cell count per leukapheresis components as well as per kg of patient's body weight were twofold higher by using the Amicus than the CS-3000+ device. Platelet contamination in Amicus components was twice as low compared to the CS3000+. Mean Amicus CD34+ collection efficiency (CD34+eff) (54.9 +/- 27.2%) was significantly higher (p < 0.015) than the CS-3000+ (46.4 +/- 16.7%) one. However, Amicus CD34+eff decreased progressively as the peripheral blood CD34+ concentrations increases over 200 CD34+ cells per microL. A parallel increase in the WBC counts in these cases seems to be the principal cause of decrease in CD34+eff (evident for WBCs >40 x 10(3)/microL and most pronounced for WBCs >60 x 10(3)/microL). CONCLUSIONS: Mean CD34+eff and CD34+ cell yields were better on Amicus than on CS-3000+. CD34+eff of Amicus, however, seems to be related to the initial WBC counts, decreasing progressively when WBC increased over 4 x 10(3) per microL that coincided with the increase in CD34+ cell concentrations. For these cases, the volume and duration of cycles should be adapted to optimize CD34+ collections by using Amicus separators.     

Comparison of intermittent- and continuous-flow cell separators for the collection of autologous peripheral blood progenitor cells in patients with hematologic malignancies

BACKGROUND: The transplantation of autologous peripheral blood progenitor cells (PBPCs) after high-dose chemotherapy is a valuable therapy for patients with hematologic and solid malignancies. Several methods are used for harvesting PBPCs. The efficiency of intermittent- and continuous-flow blood cell separators in collecting progenitor cells from the blood of patients undergoing myeloablative treatment for cancer was compared. STUDY DESIGN AND METHODS: PBPC components (n = 133) were obtained from 72 patients by leukapheresis with continuous-flow machines (Spectra, COBE; CS 3000 Plus, Baxter) and with an intermittent-flow machine (MCS 3P, Haemonetics). The data were analyzed retrospectively. Blood samples obtained from the patients before leukapheresis and samples of the leukapheresis components themselves were analyzed for their content of RBCs, WBCs, platelets, and CD34+ cells. RESULTS: The Spectra processed more than twice the blood volume in the shortest time (15 L in 178 min), whereas the Baxter CS 3000 Plus (10 L in 185 min) and the MCS 3P (4.8 L in 239 min) processed significantly smaller volumes in a longer time. The mean ACD consumption was 403 mL with the MCS 3P, 900 mL with the CS 3000 Plus, and 1000 mL with the Spectra. The product volumes were 50 mL (CS 3000 Plus), 69 mL (MCS 3P), and 166 mL (Spectra). In all groups, differences in the preapheresis hemograms were not significant, but the Spectra group had fewer CD34+ cells than the other groups. Despite this, the differences in the number of CD34+ cells in the leukapheresis components of all groups were without statistical significance. In the Spectra group, the collection of MNCs of 104 percent and CD34+ cells of 154 percent was significantly more efficient than that in the MCS 3P group (42.2% and 56%, respectively) or the CS 3000 Plus group (50.8% and 47.15%) as related to the patients' blood volume. CONCLUSION: PBPC collection can be performed successfully with continuous-flow and intermittent-flow blood cell separators. The Spectra had the best recovery of CD34+ cells within the shortest time. Leukapheresis with the MCS 3P is indicated if only a single venous access is available.     

Collection of erythroid progenitor cells by cytapheresis of peripheral blood of normal donors

Human peripheral blood may be an alternative to bone marrow as a source of cells for hemopoietic engraftment. The ability to collect large numbers of circulating granulocyte-macrophage progenitors provides support for this contention. In the present study of cells from normal granulocyte donors, the cell concentrates obtained by cytapheresis were shown to contain even greater numbers of primitive erythroid precursors (153-956 [median 647] per 10(6) mononuclear cells) than would be predicted from the peripheral blood mononuclear cell counts. Moreover, the number of primitive erythroid precursors harvested correlated significantly with the number of granulocyte-macrophage progenitors obtained and with the total lymphocyte collection. These observations further substantiate the validity of transplanting peripheral blood as hemopoietic tissue.     

Comparison of two blood cell separators in collecting peripheral blood stem cell components

To ensure that a sufficient number of CD34+ cells are collected for an allogeneic blood progenitor cell transplant, the most effective blood cell separator should be used to collect peripheral blood stem cell (PBSC) components. We compared the effectiveness of two blood cell separators. We gave 29 healthy people 7.5 or 10 μg kg^?1 of granulocyte colony stimulating factor (G-CSF) daily for 5 days and collected one PBSC component with either a Fenwal CS3000 (n = 15) or a Cobe Spectra (n = 14) blood cell separator. The volume of blood processed was the same for each machine (8.4 ± 1.0 L; range = 4.9–9.4 L for the CS3000 and 8.9 ± 1.0 L; range 6.7–10.9 L; P = 0.71). The components collected with the CS3000 contained more mononuclear cells (39.6 ± 21.9 × 10⁹ compared with 26.9 ± 5.6 × 10⁹, P = 0.02) and fewer neutrophils (1.38 ± 1.88 × 10⁹ compared with 5.53 ± 8.71 × 10⁹, = 0.001). The total number of CD34+ cells collected with the two instruments was the same (470 ± 353 × 10⁶ for the CS3000 and 419 ± 351 × 10⁶ for the Spectra; P = 0.64) as was the number of CD34+ cells collected per litre of whole blood processed (55.9 ± 42.0 × 10⁶ L^?1 compared with 45.9 ± 37.9 × 10⁶ L^?1; P = 0.59). The mononuclear cell collection efficiency was greater for the CS3000 (82.4 ± 54.9% compared with 53.3 ± 14.1; P = 0.04) but the CD34+ cell collection efficiencies were the same (87.4 ± 61.1% for the CS3000 compared with 56.3 ± 23.5% for the Spectra; P = 0.07). In conclusion, both blood cell separators collected components which contained large numbers of CD34+ cells, but those collected with the CS3000 contained fewer neutrophils and the CS3000 was more efficient at collecting mononuclear cells.     

Harvesting peripheral blood progenitor cells from healthy donors: retrospective comparison of filgrastim and lenograstim

Mobilization of CD34+ into peripheral blood is attained by either glycosylated (lenograstim) or non-glycosylated recombinant G-CSF (filgrastim). 101 donors, 57 males, median age 42 years (range 16-63) entered this retrospective study. Group I (55 cases) received filgrastim and group II lenograstim subcutaneously for 5-6 days. The peak number of CD34+ cells/microl blood observed on day 4 and 5 was not significantly different in the two groups. No differences were shown in terms of both circulating CFU-GM at the time of harvesting and CD34+ target of collection. The most frequent side effects were bone pain (18.2% grade I; 36.4% grade II, 7.3% grade III), headache (18.2%), nausea (9.1%), fever (5.5%) and a mild splenomegaly (> 2 cm) (5.5%) in filgrastim group, and bone pain (37.0% grade I, 26.1% grade II, 2.2% grade III), headache (17.4%), nausea (15.2%), fever (4.4%) and a mild splenomegaly (4.3%) in lenograstim group, respectively. CD34+ collection was associated with thrombocytopenia, which was not significantly different between the two groups. No donor in either group developed long-term adverse effects. We conclude that both G-CSFs are comparable in terms of CD34+ cell collection, safety and tolerability.     

Autologous peripheral blood progenitor cell transplantation

Harvesting of autologous peripheral blood stem cells (PBSCs) has been facilitated by using currently available, efficient apheresis technology at the time of rebound from chemotherapy while patients are receiving recombinant growth factors, i.e., granulocyte (G) or granulocyte-macrophage (GM) colony stimulating factor (CSF). Ideally pheresis should be done before patients have had extensive stem cell toxins, i.e., alkylating agents or nitrosoureas. This strategy has facilitated the use of high dose chemoradiotherapy given as a single regimen or in a divided dose for patients with solid tumors or hematologic malignancies and results in more rapid engraftment than bone marrow transplantation (BMT). Although mere are no assays which measure repopulating stem cells, enumeration of CD34⁺ cells within PBSCs is a direct and rapid assay which provides an index of both early and late long-term reconstitutive capacity, since it correlates with colony-forming unit (CFU)-GMs, as well as pre-progenitor or delta assays and long-term culture-initiating cells (LTC-IC). A threshold of ≥2 × 10⁶ CD34⁺ cells/kg recipient body weight has been reported to be required for engraftment, but may vary depending upon the clinical setting. Strategies for mobilization of normal PBSCs also increase tumor cell contamination within PB in the setting of both hematologic malignancies and solid tumors, but the significance of these tumor cells in terms of patient outcome is unclear. Recently isolation of CD34⁺ cells from PBSCs has been done using magnetic beads or immunoabsorption on columns or rigid plates in order to enrich for normal hematopoietic progenitors and potentially decrease tumor cell contamination. As for other cellular blood components, standards have been developed to assure efficient collection and processing, thawing, and reinfusion, and to maintain optimal PBPC viability. Finally, future directions of clinical research include expansion of hematopoietic progenitor cells ex vivo; use of umbilical cord or placenta as rich sources of progenitor cells; syngeneic hematopoietic stem cell transplantation; related and unrelated allogeneic hematopoietic stem cell transplantation; treatment of infections, i.e., Epstein Barr virus, or tumor relapse after allogeneic BMT using donor PBSC infusions; and gene therapy approaches.     

Comparison of performance of six different cell separators in collecting peripheral blood mononuclear cells

We compared the efficacy of six different cell separators in collecting peripheral mononuclear cells to be used for autologous or homologous peripheral stem cell transplantation. The product obtained with the Dideco Vivacell cell separator showed a low percentage of mononuclear cells (38%) in the final product and a high platelet efficiency (38%). The Baxter CS3000 Plus cell separator required the longest time to load and prime the kit (18 min), it showed a high MNC efficiency (68%), with the highest percentage of MNC in the final product, the highest platelet efficiency (45%), a low red blood cell contamination in the final product (2.7 mL), the highest extracorporeal volume (450 mL) and a high percentage of technical failures (15%). The product obtained with the Fresenius AS104 cell separator with P1Y kit showed the highest final volume (297 mL), the lowest platelet efficiency (12%) and the lowest extracorporeal volume (230 mL). The same cell separator with C4Y kit showed a lower MNC efficiency (52 vs 60%) and a higher percentage of MNC in final product (63 vs 41%). The platelet contamination in final product was the lowest (18 x 10(9)/100 mL). The Haemonetics MCS3p cell separator required the lowest time to load and prime the kit (5 min), it showed the highest MNC efficiency (71%). The blood volume processed per hour (1328 mL) and the percentage of MNC in final product was lowest (32%), the extracorporeal volume (450 mL) was the highest. The Cobe Spectra cell separator allowed to process the highest blood volume per hour (3383 mL) and the final product had the lowest red blood cell contamination (2.3 mL/100 mL). The Dideco Excel cell separator required the longest time to load and prime the kit (18 min), the lowest MNC efficiency (38%), the highest platelet contamination in final product. Furthermore this machine showed the highest percentage of technical failure (20%). None of the six instruments have all the required preconditions and the ideal cell separator for peripheral stem cell apheresis at present is not available on the market.