Prospective comparison of high-dose plateletpheresis with the latest apheresis systems on the same donors

BACKGROUND: To improve productivity of automated platelet (PLT) collection, the industry has introduced new instruments or modifications to existing equipment. STUDY DESIGN AND METHODS: With the same 8 donors for double (DDC) and triple-dose PLT collection (TDC), the Baxter Amicus (AM), the Haemonetics MCS Plus (MCS+), and the Gambro Trima Accel (TA) were evaluated focusing on yield, duration, and citrate donor load. Target endpoints were set at 5.5 x 10(11) to 6.0 x 10(11) PLTs (DDC) and 7.5 x 10(11) to 8.0 x 10(11) PLTs (TDC) in up to 100 and 120 minutes' donation time, respectively. RESULTS: TA was the most efficient system (74.5 +/- 3.9%) with significant differences from AM (71.1 +/- 3.9%; p = 0.028) and MCS+ (64.0 +/- 7.7%; p = 0.002). TA had advantages over AM for collection rate (10.9 x 10(9) +/- 2.2 x 10(9) vs. 10.1 x 10(9) +/- 1.5 x 10(9) PLTs/min; p = 0.382), whole blood processed (3928 +/- 611 mL vs. 4219 +/- 727 mL; p = 0.382), and time to obtain an established standard dose (TSD 2.5(EU), 30.2 +/- 5.6 vs. 37.7 +/- 5.5 min; TSD 3.5(US), 42.2 +/- 7.8 min vs. 52.7 +/- 7.7 min; p = 0.015), whereas AM was slightly superior in PLT yield (2.81 x 10(11) +/- 0.21 x 10(11) vs. 2.76 x 10(11) +/- 0.31 x 10(11)/unit; p = 0.645). Owing to the lowest draw (42.3 +/- 3.2 mL/min; p < 0.001) and collection rates (6.0 x 10(11) +/- 1.5 x 10(11)/min; p = 0.021), MCS+ was the slowest significantly (p < 0.001) but compensated with fewer citrate reactions owing to lower citrate infusion rates (0.78 +/- 0.11 mL/min/L; p = 0.028). CONCLUSION: High-dose plateletpheresis was performed efficiently and safely with all three instruments. AM had advantages in PLT yield, and MCS+, in donor comfort. TA was the fastest in obtaining an established standard dose and, because of this advantage, the machine with the highest practical impact in routine use.     

Comparison of plateletpheresis on the Fresenius AS.TEC 204 and Haemonetics MCS 3p

This is an attempt at comparing two cell separators for plateletpheresis, namely the Fresenius AS.TEC 204 and Haemonetics MCS 3p, at a tertiary care center in India. Donors who weighed between 55-75 kg, who had a hematocrit of 41-43%, and platelet counts of 250x10(3)-400x10(3)/microl were selected for the study. The comparability of the donors who donated on the two cell separators were analysed by t-test independent samples and no significant differences were found (P>0.05). The features compared were time taken for the procedure, volume processed on the separators, adverse reactions of the donors, quality control of the product, separation efficiency of the separators, platelet loss in the donors after the procedure, and the predictor versus the actual yield of platelets given by the cell separator. The volume processed to get a target yield of >3x10(11) was equal to 2.8-3.2 l and equal in both the cell separators. Symptoms of citrate toxicity were seen in 4 and 2.5% of donors who donated on the MCS 3p and the AS.TEC 204, respectively, and 3 and 1% of donors, respectively, had vasovagal reactions. All the platelet products collected had a platelet count of >3x10(11); 90% of the platelet products collected on the AS.TEC 204 attained the predicted yield that was set on the cell separator where as 75% of the platelet products collected on the MCS 3p attained the target yield. Quality control of the platelets collected on both the cell separators complied with the standards except that 3% of the platelets collected on the MCS 3p had a visible red cell contamination. The separation efficiency of the MCS 3p was higher, 50-52% as compared to the 40-45% on the AS.TEC 204. A provision of double venous access, less adverse reactions, negligible RBC contamination with a better predictor yield of platelets makes the AS.TEC 204 a safer and more reliable alternative than the widely used Haemonetics MCS 3p.     

In vitro quality of red blood cells (RBCs) collected by multicomponent apheresis compared to manually collected RBCs during 49 days of storage

BACKGROUND: New technologic developments enable automated collection and preparation of red blood cells (RBCs). This study's aim was to evaluate quality of apheresis-derived RBCs (ARBCs) collected as single units along with platelets (RBC-Ps) or double units (2-RBCs) with four different apheresis systems. STUDY DESIGN AND METHODS: Sixty-six donors with similar baseline variables underwent RBC apheresis collection with various machines (Amicus [15 RBC-Ps] and Alyx [15 2-RBCs], Baxter; the Trima Accel [9 RBC-Ps, 8 2-RBCs], Gambro, and the MCS+[9 RBC-Ps, 10 2-RBCs], Haemonetics Corp.). In vitro properties were analyzed during 49 days of storage and compared to manual RBCs (MRBCs, n = 14). RESULTS: All units but one, Alyx, demonstrated white blood cell counts of less than 1 x 10(6). ARBCs showed lower variability in volume compared to MRBCs. All units met international requirements (European, AABB) for hematocrit (50%-70%), hemoglobin (>40 g/unit), and RBC mass (>or=153 mL). pH values remained similar between study groups without reaching critical limits in any unit. MRBCs had slight advantages for hemolysis at the end of storage and were significantly superior in energy maintenance as indicated by less ATP degradation and potassium leak most likely due to more pronounced anoxidative glycolysis particularly during the first half of storage. Owing to more declining oxidative glucose metabolism, ARBCs demonstrated higher methemoglobin formation and subsequent oxygen release until the end of storage. CONCLUSION: ARBCs exhibited better predictability in volume and absolute RBC mass than MRBCs and demonstrated sufficient in vitro quality throughout storage, even though lower ATP preservation and higher methemoglobin formation were observed compared to MRBCs probably due to differences in glucose metabolism.     

In vivo and in vitro characteristics of double units of RBCs collected by apheresis with a single in-line WBC-reduction filter

BACKGROUND: A novel apheresis procedure for a blood separator (MCS+, Haemonetics) enables the collection of 2 WBC-reduced RBC units in a single donation by using one disposable set with one in-line WBC-reduction filter (RC2H, Pall Corp.). The objective of this study was to evaluate the filtration performance in connection with different prefiltration RBC storage conditions and with the in vitro and in vivo storage quality of the filtered units. STUDY DESIGN AND METHODS: Sixty-six 2-unit RBC collection and gravity-filtration procedures were completed at three sites, resulting in 132 RBC units. Filtration of the double RBC units was performed at room temperature (RT) within 8 hours of collection (n = 36) and under refrigeration (1-6 degrees C) for up to 24 hours (n = 10) and 72 hours (n = 20) before filtration. RBC quality was compared to that of nonfiltered apheresis RBC units (n = 10). RESULTS: Median filtration time was 6.5 and 14 minutes for units stored at RT and under refrigeration, respectively. All 132 RBC units had residual WBC counts <0.4 x 10(6). The refrigerated units showed a greater mean log reduction in WBCs: 5.06 +/- 0.16 (24 hour) and 4.74 +/- 0.48 (72 hour), respectively, than did RT units: 4.47 +/- 0.28 (p<0.05). RBC loss was less than 12 percent in all cases (mean, 7.8 +/- 1.8%). Minimal differences in volume were observed between the paired RBC units. In vitro RBC storage characteristics of the filtered units were as expected and similar to those of the nonfiltered units. For RBC units held at RT (n = 24), the mean in vivo 24-hour recovery was 81.8 +/- 8.4 percent (double-label). CONCLUSION: Satisfactory filter performance in terms of WBC removal and RBC loss was observed with all 66 procedures, irrespective of storage conditions before filtration.     

Evaluation of an automated system for the collection of packed RBCs, platelets, and plasma

BACKGROUND: This study evaluated the quality of WBC-reduced platelets, RBCs, and plasma collected on a new system (Trima, Gambro BCT) designed to automate the collection of all blood components. The study also evaluated donor safety and suitability of these components for transfusion. STUDY DESIGN AND METHODS: In Phase I, the quality of the components collected on the new system was evaluated by standard in vitro and in vivo testing methods. Results were compared to those from control components collected by currently approved standard methods. In Phase II, additional collections were performed to evaluate the acceptability of the new system and the safety of platelets collected. RESULTS: In vivo 24-hour RBC recovery was 76.8 +/- 3.1 percent for the test RBC units and 77.1 +/- 4.4 percent recovery for whole-blood (control) RBCs. The differences between test and control platelet results in the in vivo and in vitro assays were not clinically significant. Plasma clotting factors and fibrinogen levels met international standards. The system was well accepted by donors, and no major adverse donor reactions were reported for the 68 procedures performed. No problems were reported with transfusing the blood components collected. CONCLUSION: Blood components collected with the Trima are equivalent to currently available components, and they meet the applicable regulatory standards. This system provides consistent, standardized components with predictable yields. It provides the option of fully automating the collection of all blood components.     

Citrate anticoagulation and the dynamics of thrombin generation

BACKGROUND: Sodium citrate has been used as an anticoagulant to stabilize blood and blood products for over 100 years, presumably by sequestering Ca(++) ions in vitro. Anticoagulation of blood without chelation can be achieved by inhibition of the contact pathway by corn trypsin inhibitor (CTI). OBJECTIVE: To evaluate the influence of citrate anticoagulation on the performance of blood, platelet-rich and platelet-poor plasma assays. METHODS: Blood was anticoagulated in three ways: by collection into citrate, CTI and citrate with CTI. Plasma was prepared using each anticoagulation regimen. Functional analyses included calibrated automated thrombography, thromboelastography, plasma clotting, the synthetic coagulation proteome and platelet aggregation. Coagulation reactions were initiated with tissue factor-phospholipid and Ca(++) (when indicated). RESULTS: In all cases, citrate anticoagulation resulted in reaction dynamics significantly altered relative to blood or plasma stabilized with CTI alone. Subsequent experiments showed that calcium citrate itself impairs coagulation dynamics. CONCLUSION: Coagulation analyses using blood that has been exposed to citrate and recalcified do not yield reliable depictions of the natural dynamics of blood coagulation processes.     

Automated blood component collection with the MCS 3p cell separator: evaluation of three protocols for buffy coat-poor and white cell- reduced packed red cells and plasma

BACKGROUND: Automated collection of blood components with a cell separator (MCS 3p, Haemonetics), was performed according to three protocols. STUDY DESIGN AND METHODS: The first protocol provided 2 units of fresh-frozen plasma (FFP); and one buffy coat-poor red cell (RBC) concentrate in additive solution. The second protocol included an additional in-line filtration of the RBC in a closed system after storage at 4 degrees C for 24 hours. In the third protocol, an additional platelet concentrate (PC) was recovered from the buffy coat. Cell counts and biochemical characterization of the RBCs (n=20 each) were determined on Days 0, 1, 14, 28, and 49. RESULTS: The RBC volume was 336 +/? 9 mL (first protocol), 337 +/? 7 mL (second protocol) and 293 +/? 12 mL (third protocol) with a hematocrit of 59 +/? 2, 53 +/? 3, and 61 +/? 5, percent respectively. On Day 49, hemolysis was 0.24 +/? 0.1 percent (first protocol), 0.33 +/? 0.32 percent (second protocol), and 0.38 +/? 0.1 percent (third protocol). The filtered RBC concentrate met the international standards for white cell-reduced RBCs. Filtration resulted in a clinically irrelevant increase of hemolysis. The in vitro RBC values (lactate dehydrogenase, 2-hydroxybutyrate dehydrogenase, hemolysis, potassium, 2,3 DPG, ATP) were at least equal to those in RBCs collected by conventional whole-blood donation. There is a trend toward extended preservation of 2,3 DPG in RBCs collected by apheresis. Two units of FFP could be collected with each donation (first protocol: 420 +/? 55 mL, 5.4 +/? 7 WBCs/microL, 6.5 +/? 5 × 10(3) platelets/microL; second protocol: 440 +/? 33 mL, 3 +/? 5.2 WBCs/microL, 32 +/? 12 × 10(3) platelets/microL; third protocol: 398 +/? 32 mL, 5 +/? 12 WBCs/microL; 3.4 +/? 3.5 × 10(3) platelets/microL). PCs prepared from the buffy coat collected by the third protocol contained 90 +/? 30 × 10(9) platelets in 88 +/? 14 mL of plasma. In vitro test results in these PCs were superior to those in PCs collected by conventional whole-blood donation. The procedure was well tolerated by all donors. No adverse reactions appeared. CONCLUSION: Erythroplasmapheresis with the MCS 3p cell separator is a useful alternative to conventional whole-blood donation and separation.     

Fuji surge technique and continuous in-line filtration to improve the quality of single donor platelet concentrates

White blood cell (WBC)-reduced single donor platelet concentrates (SDPs) can be collected by most cell separators. WBC reduction can be achieved directly during plateletpheresis or by filtration. Continuous filtration with low filtration rates provides SDPs of good purity. To compensate the platelet (PLT) loss due to filtration, the PLT yield in the unfiltered primary product should be optimal. Fifty donors underwent plateletpheresis with the MCS+ blood cell separator (Haemonetics) with the new Fuji surge technique and continuous WBC filtration. Twelve SDPs were analysed for PLT yield, red blood cells (RBC), WBC, and pH after collection (Day 0) and at the end of storage (Day 5). Thereafter, further 38 SDPs were measured for PLT and WBC content in routine production at Day 0. PLT were determined electronically, RBC and WBC were counted manually (Neubauer and Nageotte chamber, respectively). For pH measurement, a pH-meter was used. Mean blood volume processed was 2621 +/- 112 ml in a donation time of 76 +/- 10 min. An average PLT yield of 3.45 +/- 0.88 x 10(11) was collected in a product volume of 325 +/- 77 ml. The collection efficiency was 60.0 +/- 5.5%. WBC contamination of all units tested was 0.046 +/- 0.059 x 10(6) and the RBC content of the SDPs analysed at Day 0 was 0.014 +/- 0.003 x 10(9). The pH was well maintained over the storage period of 5 days. The data indicate that Fuji surge technique and continuous in-line leukocyte filtration allow for the collection of SDPs with high platelet yield and low leukocyte contamination, meeting the Council of Europe quality standards.     

Evaluation of a concurrent multicomponent collection system for the collection and storage of WBC-reduced RBC apheresis concentrates

BACKGROUND: Multicomponent apheresis procedures offer the possibility of collecting blood components that are standardized, as compared to those available with whole-blood donations. A new separator program for the concurrent collection of RBCs, platelets, and plasma (Amicus, Baxter Healthcare) was evaluated. STUDY DESIGN AND METHODS: Apheresis donors (n = 47) underwent concurrent collection of RBCs, platelets, and plasma by use of the single-needle procedure of the Amicus blood cell separator. A standardized RBC volume (100% Hct) of 200 mL was targeted with either 1 or 2 platelet concentrate units, depending on the donor's predonation characteristics. After collection, the RBC component was sterilely connected to an RBC collection set (Amicus) to allow for the addition of 100 mL of saline-adenine-glucose-mannitol preservative solution and WBC reduction at either ambient temperature or 4 degrees C. The RBC units were subsequently stored at 2 to 6 degrees C for 42 days, and the following in vitro measures were evaluated over the storage period: blood cell counts including Hct and total Hb, plasma Hb, potassium, pH, ATP, and 2,3 DPG. RESULTS: Procedure time averaged 74 +/- 9 minutes, and no adverse events were reported. The absolute RBC volume collected averaged 198 +/- 11 mL with an average Hct value of 83 +/- 2 percent. After filtration, the Hb content averaged 58.2 +/- 2.4 g per unit and residual WBCs averaged 0.038 +/- 0.015 x 10(6) per unit. Day 42 results showed that all units had on average more than 70-percent ATP maintenance, and all of the units had less than 0.8 percent he-molysis. All units had pH values higher than 6.5 on Day 42. CONCLUSION: The concurrent multicomponent collection system (Amicus) can reliably collect a standardized RBC unit of good quality. In vitro testing of the RBCs collected and stored for 42 days met the Council of Europe criteria for transfusion.     

The relative safety of automated two-unit red blood cell procedures and manual whole-blood collection in young donors

BACKGROUND: Automated red blood cell (RBC) apheresis offers the advantage of collecting 2 units of RBCs (2RBC) from one donation, but may expose donors to procedure-related risks. This study evaluated the relative safety of 2RBC compared to whole-blood (WB) donation with a focus on young donors.
STUDY DESIGN AND METHODS: Adverse reactions recorded at the collection site or requiring outside medical care were compared after 4,348,686 WB and 206,570 2RBC donations in 26 regional blood centers.
RESULTS: 2RBC donors were more likely than WB donors to be male (91.6% vs. 50.3%) and repeat donors (84.0% vs. 81.0%). The overall complication rate was higher for 2RBC than WB collections (627.9 vs. 435.1 per 10,000; odds ratio [OR], 1.44; 95% confidence interval [CI], 1.41-1.47), but more than 96% of all reactions were minor in severity. For donors younger than 20 years, adverse events were equally or less common after 2RBC than after WB donation, but were more common after 2RBC for donors 20 years or older. The rate of major systemic complications was significantly lower for 2RBC than WB donations in all age groups (10.2 vs. 14.3 per 10,000 collections; OR, 0.71; 95% CI, 0.62-0.82). Overall, the need for outside medical care was similar for 2RBC and WB collections (3.4 vs. 4.2 per 10,000 donations, respectively), but significantly less likely after 2RBC donation for donors less than 20 years old (3.8 vs. 7.0. per 10,000 donations; OR, 0.53; 95% CI, 0.32-0.89).
CONCLUSION: 2RBC collection procedures, as currently performed in the American Red Cross, are associated with fewer immediate adverse reactions in young donors and have a comparable safety profile in older donors. These data support the collection of 2RBC from young donors.     

Characterization of blood components prepared from whole-blood donations after a 24-hour hold with the platelet-rich plasma method

BACKGROUND: The preparation of platelet (PLT) concentrates (PCs) from PLT-rich plasma (PRP) requires that whole blood (WB) be processed within 8 hours of collection. Increasing WB storage time to 24 hours would be logistically attractive. This study compares the in vitro quality of blood components prepared from WB stored for 8 and 24 hours at room temperature before processing with the PRP method. STUDY DESIGN AND METHODS: WB units were collected from ABO-matched blood donors. To reduce individual variations, paired donations were drawn in parallel, pooled, and split back in the collection bag. One unit was held for 6 to 8 hours and the other for 22 to 24 hours at 20 to 24 degrees C. Prestorage leukoreduced components were prepared with the PRP as intermediate product and analyzed during storage. RESULTS: RBC units prepared after an 8- or 24-hour hold were comparable in terms of hemolysis, sodium, pH, and ATP levels. RBC 2,3- diphosphoglycerate (2,3-DPG) was significantly lower in RBCs prepared from 24-hour hold donations immediately after processing but not after 20 days of storage. Residual white blood cells were approximately fivefold higher (p < 0.05) in 24-hour RBC units. For PCs, measurements for glucose, ATP, lactate, pH, extent of shape change, hypotonic shock response, and CD62p activation were similar. No differences were observed in the von Willebrand factor, factor (F)V, FVIII, and fibrinogen content of fresh-frozen plasma. CONCLUSIONS: The decrease in FVIII and RBC 2,3-DPG can be acceptable as a compromise to improve blood component logistics, but leukoreduction efficiency must be improved before considering the adoption of an overnight storage of WB before PRP processing.     

Donor survey to assess facial flushing during automated red cell collections and medication use

Background: We conducted a donor survey to assess the occurrence of facial flushing and other symptoms during automated 2‐U red cell collections (2RBC) and plateletpheresis (PLT) procedures and evaluated the possible association of the reactions with angiotensin‐converting enzyme (ACE) inhibitors or with the collection technology. Methods: An online survey was developed using Zoomerang to capture details of the donors' experience and medication use after 2RBC or PLT donations in regional blood centers of the American Red Cross. Results: Between 12/16/09 and 4/19/10, 1,299 donors in five American Red Cross blood center regions completed an online survey (739 2RBC, 4.2% total registrations; 560 PLT, 2.3% total registrations). Facial flushing was reported by 29 donors, and was more likely associated with 2RBC than PLT procedures (3.0% vs. 1.3%, P = 0.03). Facial flushing with 2RBC donation was reported by eight of 72 (11%) donors on ACE inhibitors; and 14 of 667 (2%) donors who were not taking ACE inhibitors (P = 0.001). The incidence of facial flushing reactions with PLT donation was less than 2% whether donors reported ACEI inhibitor use or not. More than 95% of the donors reported their intent to donate again, regardless of symptoms. Conclusion: Facial flushing was more often reported by 2RBC donors taking ACE inhibitors than other donors [11% vs. 2%; P = 0.001]; and was uncommon among PLT donors, irrespective of ACE inhibitor use (<2%). All blood donors should be informed of the potential for common, minor side effects of the collection procedure and the possible but rare occurrence of more medically serious complications. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.     

Effects of whole blood flow rates on mononuclear cell yields during peripheral blood stem cell collection using fenwal CS 3000 plus

It is generally assumed that using high whole blood flow rates (WBFR), 80 ml/min, during peripheral blood stem cell (PBSC) collection on the Fenwal CS 3000 Plus blood cell processor will result in higher yields of mononuclear cells (MNC) than using lower WBFR (50 ml/min). To test this assumption, we retrospectively studied 129 PBSC procedures on 17 patients in a multiple myeloma protocol comparing MNC yield, as well as red blood cell (RBC), granulocyte, and platelet (Plt) content, of four average WBFR groups. Standard PBSC procedures were performed using modified procedure 1, interface offset 100, anticoagulant (AC) ratio of 11:1, small volume collection chamber, and a processing time of 4 hours. After correcting for AC volume used, the volume processed was divided by 240 minutes to obtain the average WBFR. WBFRs were separated into 4 groups of 40–49, 50–59, 60–69, and 70–79 ml/min. When compared to the highest flow rate group (70–79 ml/min), the three lower flow rate groups had significantly higher MNC yields of 16.2 ± 6.9, 13.1 ± 5.1, and 11.5 ± 4.7 × 10⁹, respectively, as compared to 8.9 ± 6.1 ± 10⁹ MNC for the 70–79 ml/min group. There was no significant difference in granulocyte yield which ranged from 1.6 ± 2.1 to 4.5 ± 4.8 × 10⁹. There were also significantly more RBC in the 70–79 ml/min group with 21.1 ± 2.2 ml than all three other groups with 16.2 ± 4.3, 16.6 ± 4.0, and 17.9 ± 4.2 ml, respectively, but high average WBFR collected significantly less platelets (0.6 ± 0.7 × 10¹¹ versus 1.9 ± 1.0, 1.5 ± 0.9, and 1.2 ± 0.9, respectively). Incidence of citrate reactions increased as flow rates increased, 6%, 18%, 30%, and 33%, respectively. We conclude that using a lower average WBFR during PBSC collection actually produced significantly more MNC, with equivalent granulocytes, less RBC, but more platelets than the high average WBFR.     

Improved collection of mobilized CD34+ hematopoietic progenitor cells by a novel automated leukapheresis system

BACKGROUND: For simplification of blood cell transplantation, an automated apheresis system that exploits a dual-stage channel device for mononuclear cell (MNC) collection (Au-toPBSC, designed for the COBE Spectra) was studied. STUDY DESIGN AND METHODS: The automated default software (AutoPBSC-Default) and three software modifications of the harvest frequency during leukapheresis, referred to as Au-toPBSC-1.25, AutoPBSC-1.75, and AutoPBSC-2.75, were evaluated in comparison with the semiautomated Version 4.7 (V4.7) apheresis system in 119 leukapheresis procedures performed in 90 cancer patients treated with chemotherapy plus granulocyte–colony-stimulating factor. CD34+ cell and platelet collection efficiency (CE); volume and cell composition of the leukapheresis components; and patient platelet and red cell (RBC) loss during leukapheresis were measured. RESULTS: The majority of collection measures evaluated with the AutoPBSC compared favorably to those obtained with the V4.7. CD34+ cell CE increased from 55 percent with V4.7 to 68 percent with the AutoPBSC-Default (p = 0.05). The AutoPBSC provided lower platelet contamination in the collected component (1.18 × 10¹¹ vs. 2.26 × 10′′ with the V4.7;p< 0.001). The volume of the AutoPBSC-Default component was significantly lower (67 vs. 180 mL with the V4.7; p<0.001). The MNC purity of the AutoPBSC component was greater (52 vs. 28% with the V4.7; p<0.001), and the RBC contamination lower (AutoPBSC, 0.53 × 10¹¹ vs. 1.04 × 10¹¹ with the V4.7; p<0.001). Modifications of the AutoPBSC to increase the harvest frequency by 1.25-, 1.75-, and 2.75-fold resulted in increased CD34+ cell CE (77%, 75%, and 83%, respectively; p<0.001 in all cases), but also in reduced numbers of circulating platelets, higher platelet contamination of the component, and lower MNC purity than were seen with the AutoPBSC-Default. CONCLUSION: The AutoPBSC offers the following advantages over the V4.7 system: a) better CE of CD34+ cells; b) reduced collection of platelets; c) reduced contamination of the leukapheresis component with granulocytes, platelets, and RBCs; d) reduced component volume; and e) automation.     

Paired crossover study of two plateletpheresis systems concerning platelet product quality and donor comfort

BACKGROUND: Two plateletpheresis cell separator systems were compared in a paired crossover study with respect to the product quality, the number of platelet (PLT) units per donation, and the donor comfort. STUDY DESIGN AND METHODS: Forty‐four female and 47 male donors were distributed to three body weight groups. Double PLT units with 6 × 10¹¹ PLTs were collected from three Fenwal Amicus Crescendo (AC) and three CaridianBCT Trima Accel (TA) machines. Each donor made one donation on each randomly assigned system and answered a questionnaire on the subjective donor comfort. The answers were scored from 5 (best) to 1 (worst). RESULTS: Based on 182 donations, with 91 donations on AC and TA separators each, 179 runs resulted in double PLT units and three (2×AC, 1×TA) in single units. The white blood cell counts were below 1 × 10⁶ in all but eight therapeutic units (8×TA; mean, 1.98 × 10⁶). The mean PLT yield (AC 6.00 × 10¹¹, TA 5.98 × 10¹¹), the collection rate, and the PLT extraction coefficient did not significantly differ between the two devices. Differences of the donor comfort over all groups were only observed for the loudness of the instrument (4.63 AC vs. 4.24 TA, p < 0.001) and the subjective impression of the run time (4.24 AC vs. 4.48 TA, p < 0.05). Male donors greater than 88 kg preferred the TA instruments concerning the impact of the needle, run time, overall experience (p < 0.01 each), and willingness to donate on the same instrument again (p < 0.05). CONCLUSIONS: Only minor differences were observed despite the fact that the AC separators are run with two needles and the TA with one needle.     

Plateletpheresis: what's new?

1995 has brought several novelties into the field of thrombocytapheresis. The most important is the presentation by Baxter of the Amicus CFC apparatus that, in a two-vein collection time of 51-53 min, collects 3.93-4.13 x 10(11) platelets contaminated by 0.2 x 10(6) white blood cells (WBC) with an efficiency of 72-74%. Similar results are obtained in 55 min, in single-needle procedures, with a collection efficiency of 70.7%, a total yield of 4.3 x 10(11) and a contamination of 0.9 x 10(6) WBC. Presently the machine cannot collect red blood cells (RBC), along with platelets, as does the DFC Haemonetics MCS3p. With this machine in mandatory single-needle procedures lasting 80-85 min, approximately 4.5 x 10(11) platelets can be collected with a WBC contamination of 3.1 x 10(6). Along with the platelet cells (PC), with the SDP PRC protocol at the end of each pass it is possible to collect aliquots of plasma red blood cells (PRBC) (10-50 mL) with a haematocrit of 65%. Depending on the number of passes and on the donor's body weight (BW), from 1 and 2 U/PRBC containing approximately 55 g of haemoglobin (Hb) each can be obtained. This method not only costs less but also immunological and viral risks for the patients are more efficiently addressed since it is possible to reduce the number of allogeneic exposures in the same transfusion event. PRBC can also be collected with the Fresenius AS104 and the Dideco Excel apparatuses. Dideco is presently using the "Genova" separation chamber, which can collect an average of 4.8 x 10(11) platelets contaminated with 0.5 x 10(6) WBC, in approximately 55 min. The ACD-A-to-blood ratio may be as low as 1/20 since the very last belts and lines are coated with non-thrombogenic substances. Therefore, there is no alteration of the quality of the platelets as evaluated with monoclonal antibodies (MoAbs) anti-CD 62, 63, 36 and 51, no extra haemorrhagic risk for the donors and citrate reactions and microaggregate formation are totally eliminated. In 1995 there has also been some rejuvenation of the older cell separators. The CS3000+ uses the TN6/PLT 30 combination of separation collection chambers. Platelets are collected in only 30 mL of plasma, and non-plasma solutions containing acetate can be used for their resuspension. The Fresenius AS204 is ready for better-quality combined platelet collection, and RBC-PC collection with Cobe Spectra is under evaluation along with the leucocyte reduction system that apparently brings leucocyte contamination down to 0.35 x 10(5). This interest in thrombocytapheresis is also the result of the challenge that thrombopoietin phase I and II trials have promoted.     

PBSC collection from G-CSF primed donors

Peripheral blood stems cells (PBSCs) have been used in autologous transplantation as an alternative to bone marrow-derived cells. Recently, PBSCs have been collected from healthy donors after priming with G-CSF and used for allogeneic transplantation. We have a comparatively large experience with PBSC collection in autologous and allogeneic settings. The five cell separators we employ are: the CS3000 plus, AS 104, Excel, Cobe Spectra and MCS 3p. These machines appear to have different efficacies but no studies have been carried out on this topic. In a prospective study we have randomly assigned donors to different cell separators to evaluate their efficiency. Twenty-five donors underwent the procedure and 50 leukaphereses were carried out. Donors were given 5 micrograms kg-1 d-1 of recombinant human G-CSF for 3 days and 10 micrograms kg-1 d-1 for 4 days subcutaneously. Leukaphereses were performed on days 6 and 7 of G-CSF administration. The results of our study show that a total value of CD34+ cells ranging from 48.44 x 10(6) to 270.37 x 10(6) can be collected from donors with a white cell count ranging from 40.50 x 10(3) microL-1 to 51.34 x 10(3) microL-1 and mononuclear cells ranging from 16.42 to 20.37%. The Excel and the MCS 3p seem to differ from the other machines in terms of higher CD34+ cell collection efficiency. The Excel appears to be even more efficient than the MCS 3p, but this may not reflect reality because the Excel processes 12 L of blood while the MCS 3p employs an 8 L procedure. All the machines showed satisfactory results in terms of yield and quality of the harvests.     

The safety profile of automated collections: an analysis of more than 1 million collections

BACKGROUND: Recent technology allows for the collection of 2-unit red cells (RBCs) and single-unit RBCs plus plasma or platelets (PLTs). STUDY DESIGN AND METHODS: With a common definition of adverse events, 1,023,682 whole-blood collections were evaluated and compared with 249,154 two-unit apheresis RBC collections, 40,870 single-apheresis RBC collections, and 90,082 apheresis PLT collections. RESULTS: The data show that manual whole-blood collections have a low incidence of moderate and severe reactions (47.1 per 10,000 collections, 0.47%). Single-unit RBCs collected by apheresis have the same safety profile (37.44 per 10,000 collections, p > 0.20). Double-RBC collections by apheresis and plateletpheresis have a significantly lower reaction rate (15.65 per 10,000 collections, p < 0.00005; and 14.84 per 10,000 collections, p < 0.00005, respectively). CONCLUSION: It is concluded that automated collections are safe or safer than manual whole-blood collections. There should be few concerns when procedures are performed according to manufacturer's instructions.     

The value of pH as a quality control indicator for apheresis platelets

BACKGROUND: Standards and regulations require measurement of pH as an apheresis platelet (PLT) component quality monitor. The usefulness of this quality control (QC) measure was investigated. STUDY DESIGN AND METHODS: QC data were retrospectively reviewed for apheresis PLTs collected over 4.5 years. Three collection devices were used, the Amicus (Baxter), the CS-3000 Plus (Baxter), and the MCS+ LN9000 (Haemonetics). Each month, four components from each instrument were sampled. PLT counts and component volume were measured immediately after collection, and pH, after 5 days of storage. RESULTS: A total of 668 products were studied. pH decreased as PLT concentration increased (r(2) = 0.129, p < 0.001) and as component volume decreased (r(2) = 0.086, p = 0.02). PLT concentration and volume, however, were poor predictors of a low pH. Apheresis instrument type affected pH. The 216 components collected with use of the CS-3000 device had a lower pH than components from the other two instruments. Only 13 components had a pH value less than the acceptable level of 6.2, 12 of which were collected with the CS-3000. CONCLUSIONS: For newer-model blood cell separators, pH measurements do not provide information that might identify a manufacturing problem. Because factors that influence pH are controlled or monitored for each component, evaluation of pH on a sample group provides an indication of the quality of specific component only, rather than an effective monitor of the quality of the manufacturing process.     

The effects of cryopreservation on red blood cell microvesiculation, phosphatidylserine externalization, and CD47 expression

BACKGROUND: Since the 1950s, cryopreservation has been used in transfusion medicine for long-term storage of phenotypically rare red blood cells (RBCs). Recent reports have identified phosphatidylserine (PS) exposure, loss of CD47 expression, and membrane microvesiculation as important indicators of RBC storage lesion and in vivo survival. The purpose of this study was to assess the effects of RBC cryopreservation and prefreeze storage length on these novel markers of membrane injury and to correlate them to traditional RBC quality indicators. STUDY DESIGN AND METHODS: Leukoreduced RBC units were collected in citrate-phosphate-dextrose (CPD)-saline-adenine-glucose-mannitol (SAGM), hypothermically stored (1-6 degrees C) for 2 to 3 days or 13 to 14 days after collection, and then cryopreserved in 40 percent (wt/vol) glycerol. In vitro RBC quality was assessed before freeze, after thaw, and 24 hours after thaw by evaluating RBC recovery, hemolysis, sterility, residual glycerol, adenosine triphosphate, extracellular potassium, RBC indices, and morphology. RBC membrane microvesiculation, PS externalization, and CD47 expression changes were evaluated using flow cytometry. RESULTS: Leukoreduced CPD-SAGM RBCs showed acceptable in vitro quality after deglycerolization, according to conventional assays. Cryopreservation alone did not induce significant changes in PS exposure, CD47 expression, and membrane microvesiculation. Prolonged prefreeze storage, however, resulted in a significant increase in RBC PS exposure and microvesiculation after 24 hours of postthaw hypothermic storage (1-6 degrees C). No significant changes in CD47 expression were detected. CONCLUSION: High-glycerol cryopreservation does not induce microvesiculation, PS exposure, and loss of CD47 expression in RBC membranes. Since prolonged prefreeze storage can result in RBC membrane injury during the postdeglycerolization storage period, more defined criteria for this variable should be adopted.