30 results on '"Ringwald J"'
Search Results
2. Why Do Some Apheresis Donors Donate Blood Just Once?: SP229
- Author
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Ringwald, J, Lange, N, Rabe, C, Zimmermann, R, Strasser, E F, Hendelmeier, M, Strobel, J, and Eckstein, R
- Published
- 2007
3. Recruitment of Monocyte Subpopulations by Leukocytapheresis in Healthy Blood Donors: SP68
- Author
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Hendelmeier, M, Hartmann, M, Strasser, E F, Ringwald, J, Weisbach, V, Zimmermann, R, and Eckstein, R
- Published
- 2007
4. Washing Platelets With New Additive Solutions—Aspects On The In Vitro Quality After 48 Hours Of Storage: SP146
- Author
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Ringwald, J, Althoff, F, Zimmermann, R, Strasser, E F, Weisbach, V, Zingsem, J, and Eckstein, R
- Published
- 2005
5. Short-Term Storage Of Platelet Split Products Intended For Neonatal Transfusion: S17-030D
- Author
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Strasser, E F, Stachel, D K, Zimmermann, R, Schwarzkopf, P, Ringwald, J, and Eckstein, R
- Published
- 2005
6. Storage of Apheresis Platelets in Two New Additive Solutions
- Author
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Ringwald, J, Zimmermann, R, Strasser, E, Achenbach, S, Weisbach, V, Zingsem, J, Antoon, M, and Eckstein, R
- Published
- 2003
7. Apheresis of Immunocompetent Cells: A Paired Study to Compare Two MNC Programs on Two Apheresis Devices
- Author
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Strasser, E F, Weisbach, V, Zimmermann, R, Ringwald, J, Zingsem, J, and Eckstein, R
- Published
- 2003
8. Comparison of Productivity and Citrate Donor Load between the Trima Version 4 and the Accel in the Same Donors
- Author
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Ringwald, J, Zingsem, J, Zimmermann, R, Strasser, E, Antoon, M, and Eckstein, R
- Published
- 2003
9. CD 14+ cell collection in non-cytokine-stimulated donors with the COM.TEC cell separator.
- Author
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Strasser EF, Hendelmeier M, Weisbach V, Zimmermann R, Ringwald J, Juntke R, Sauer G, Zingsem J, and Eckstein R
- Abstract
BACKGROUND: The COM.TEC cell separator (Fresenius Hemocare), equipped with the MNC program (single-stage chamber) and the PBSC-LYM program (dual-stage chamber), was evaluated for CD 14+ cell collection regarding cell yields, collection efficiencies (CEs), and the content of residual cells in harvests. STUDY DESIGN AND METHODS: Twenty-four non-cytokine-stimulated donors underwent 5-L mononuclear cell (MNC) collections on the COM.TEC device to compare both programs. Two software versions (v02.03.05 vs. v 03.00.04) were investigated for optimization of the CD 14+ cell collection process. Blood counts of donors and products were analyzed for CD 14+ cells by flow cytometry and for platelets (PLTs), white blood cells, and red blood cells (RBCs) by a blood cell counter. RESULTS: In 5-L collections, the MNC program resulted in high CEs (83+/- 23%) and yields (1.2 x 10(9)+/- 0.6 x 10(9) per unit) of CD 14+ cells, but the products showed high residual PLTs. The use of a dual-stage chamber in the PBSC-LYM program produced a low content of residual PLTs (0.7 x 10(11) +/- 0.3 x 10(11) per unit) and RBCs but failed to reach a target of 1 x 10(9) CD 14+ cells. Modulated light to stabilize the buffy-coat detection by the interface monitor significantly improved CD 14+ cell enrichment. By use of the PBSC-LYM program, higher centrifuge velocity (1700 rpm [382 x g] vs. 1500 rpm [297 x g]) improved significantly CD 14+ cell yields (0.7 x 10(9) vs. 0.5 x 10(9) cells). CONCLUSION: A pure CD 14+ cell product with low numbers of residual cells was obtained by the PBSC-LYM program, which could be useful for good manufacturing practice-conformed production within closed systems. The MNC program offers the collection of high CD 14+ cell yields with excellent CEs but also high residual PLT counts. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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10. Processing of Human Umbilical Cord Blood Cells Using an Automated Functionally Closed System.
- Author
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Zingsem, J., Weisbach, V., Zimmermann, R., Strasser, E., Fischer, T., Ringwald, J., and Eckstein, R.
- Subjects
CORD blood ,BLOOD cells ,STEM cells - Abstract
Background: Human umbilical cord blood (HUCB) cells have been used successfully as an alternative stem cell source for transplantation. However, the volume reduction (VR) process prior to cryoconservation may cause cell losses up to 40% and more of the progenitor cells. Furthermore, the established VR techniques are time consuming, poorly standardized, and performed in open blood bag systems. We therefore evaluated a new automated device using a functionally closed system. Study design and methods: 20 HUCB donations were assigned randomly to processing either using the SEPAX S-100 (Biosafe SA, Eysins, Switzerland) cell separator, designed for processing low volumes of blood or using the separation technique in blood bags as described by Rubinstein et al. The processing performance was assessed on processing time, volume reduction efficiency, the recovery of nucleated cell (NC), mononuclear cells (MNC), and CD34+ cells. Results: The mean recovery was 78.3% ± 15.6% vs. 72.9 ± 26.2% for NCs, 77.9 ± 15.7% vs. 74.7 ± 30.7% for MNCs, and 87.1 ± 28.0% vs. 85.7 ± 15.1% for CD34+ cells comparing the Sepax to the standard blood bag procedures. The differences were not significant. The processing time was 20 Minutes for the Sepax procedures and 60-80 Minutes for the reference procedures. Conclusion: Using the Sepax cell separator, HUCB transplants can be processed prior to cryopreservation in less than one third of the time needed for conventional blood bag processing. The processing results are reproducible and slightly but not significantly better than the results obtained by blood bag procedures. As the machine works using a closed system connected to the collection bag, the risk of bacterial contamination during processing is as small as in routine blood collections. Thus the machine is an useful tool for product standardization in cord blood banking. [ABSTRACT FROM AUTHOR]
- Published
- 2001
11. Human immunodeficiency virus 1 dual-target nucleic acid technology improves blood safety: 5 years of experience of the German Red Cross blood donor service Baden-Württemberg-Hessen.
- Author
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Hourfar K, Eberle J, Müller M, Micha Nübling C, Chudy M, Kress J, Gürtler L, Mayr-Wohlfart U, Schrezenmeier H, Hellmann I, Luhm J, Kraas S, Ringwald J, Gubbe K, Frank K, Karl A, Tonn T, Jaeger M, Sireis W, Seifried E, and Schmidt M
- Subjects
- Blood Safety, Donor Selection, Female, Germany, Humans, Male, Red Cross, Retrospective Studies, Blood Donors, HIV Long Terminal Repeat, HIV-1 genetics, HIV-1 metabolism, RNA, Viral blood, RNA, Viral genetics, Reagent Kits, Diagnostic, Reverse Transcriptase Polymerase Chain Reaction, gag Gene Products, Human Immunodeficiency Virus blood, gag Gene Products, Human Immunodeficiency Virus genetics
- Abstract
Background: RNA viruses are associated with a high frequency of mutations because of the missing proofreading function of polymerases, such as reverse transcriptase. Between 2007 and 2010, six blood donations with false-negative nucleic acid technology (NAT) results were reported in Germany. Therefore, NAT screening in two viral genome regions was introduced by our blood donation service in 2010 on a voluntary basis and became mandatory in Germany since the beginning of 2015., Study Design and Methods: Blood donor screening was done using, in parallel, the German Red Cross (GRC) HIV-1 CE long terminate repeats (LTR) PCR kit and the GRC HIV-1 gag CE PCR kit. In total, 7 million blood donations were screened during the study period from 2010 to 2014 with the GRC dual-target human immunodeficiency virus 1 (HIV-1) NAT system. Additionally, three suspicious specimens were analyzed by four monotargeted NAT assays and by five dual-target NAT assays., Results: Three of 7 million donations tested negative using the 5'LTR-polymerase chain reaction, but they were positive if amplification was performed in the gag region. HIV antibodies were detected in all three donations. Nucleic acid sequence analysis identified a deletion of 22 bases within the 5'LTR probe binding region. Three different ltr-based monotargeted assays missed two donations, except for a low-reactive result obtained by one of the assays. In total, the detection rates for HIV-1-positive donations were 37.5% (3/8) for monotargeted assays and 100% (10/10) for dual-target assays., Conclusion: The current data demonstrate that dual-target NAT systems reduce the risk of false-negative HIV-1 NAT screening results., (© 2018 AABB.)
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- 2018
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12. von Willebrand factor, clotting factors, and clotting inhibitors in apheresis platelet concentrates.
- Author
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Weiss DR, Franke D, Strasser EF, Ringwald J, Zimmermann R, and Eckstein R
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- Blood Coagulation Factors metabolism, Humans, Plateletpheresis, Blood Platelets metabolism, von Willebrand Factor metabolism
- Abstract
Background: Apheresis platelet concentrates (APCs) are usually stored in citrated plasma at 22°C. The stability of coagulation proteins-von Willebrand factor (vWF), clotting factors (CFs), and their inhibitors-has often been described in association with the storage of thawed plasma. However, fewer data are available regarding changes in APCs., Study Design and Methods: We measured CF activities and inhibitors in APCs on the day of manufacture (Day 0) and on Days 4, 5, and 7. vWF was determined by measuring vWF antigen (vWF:Ag) and vWF ristocetin cofactor (vWF:RCo) and by multimer analysis., Results: Twenty-one PCs obtained by plateletpheresis were studied. Major changes were observed for Factor (F)VIII (37% loss of activity within 4 days), FV (20% within 4 days), and protein S (76% within 4 days). All other CF activities remained higher than 80% over the 7 days. Fibrinogen and the inhibitors antithrombin and protein C remained quite stable. FXI, FXII, and FXIII actually increased during storage (8, 11, and 12% within 4 days). vWF:Ag increased during storage of APCs by 2% per day, with a relative loss of vWF:RCo and high-molecular-weight multimers., Conclusion: Even after 7 days of storage at 22°C, the hemostatic potential of the plasma content in APCs was roughly preserved. The increase in FXII antigen indicates that this CF may also be stored in platelets; however, this has not yet been described., (© 2013 American Association of Blood Banks.)
- Published
- 2014
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13. Effects of immediate or delayed addition of platelet additive solution on the in vitro quality of apheresis platelets.
- Author
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Ringwald J, Tully S, Geier C, Hauck B, Weiss D, Callaert M, and Eckstein R
- Subjects
- Blood Donors, Blood Platelets metabolism, Blood Preservation adverse effects, Blood Preservation methods, Cell Shape drug effects, Drug Administration Schedule, Female, Humans, Hypotonic Solutions adverse effects, Hypotonic Solutions pharmacology, In Vitro Techniques, Male, Organ Preservation Solutions administration & dosage, Organ Preservation Solutions adverse effects, P-Selectin metabolism, Platelet Activation physiology, Quality Control, Time Factors, Blood Platelets cytology, Blood Platelets drug effects, Organ Preservation Solutions pharmacology, Platelet Activation drug effects, Plateletpheresis adverse effects, Plateletpheresis methods
- Abstract
Background: There is little knowledge how different hold times of hyperconcentrated platelet (PLT) suspensions (HPSs) before the addition of platelet additive solution (PAS) might affect PLT quality. We compared the in vitro quality of single-donor PLT concentrates (SDPs) with immediate or delayed PAS addition and studied the quality of collected concurrent plasma (CP)., Study Design and Methods: We collected 6×10(11) PLTs in 175 of mL plasma and CP from 31 donors. The HPSs were split into two parts, with 162 mL of modified PAS III (PAS-IIIM) added immediately (0hr-SDP) or 2 hours later (2hr-SDP). Final SDPs had a targeted concentration of 1.2×10(12) PLTs/L and a PAS proportion of 65%. On Days 1, 5, and 7 we determined glucose and lactate concentration, pH, P-selectin expression, hypotonic shock response (HSR), and extent of shape change (ESC). Clotting Factor V (FV) and VIII (FVIII) activities and D-dimer concentration were determined in CP and donor., Results: Glucose utilization, lactate production, and pH were similar for both kinds of products. Low P-selectin expression indicated no relevant PLT activation during storage. HSR and ESC were similarly well preserved. Recoveries of FV and FVIII were 100.0±14.0 and 98.6±14.9%, respectively. Concentrations of D-dimers in the donor and CP were 173.7±90.1 and 177.6±91.2 ng/dL, respectively., Conclusions: Adding PAS immediately or 2 hours after collection does not result in different in vitro quality of PLTs stored up to 7 days. The good recovery of clotting factors with no signs of activation indicates a good quality of CP., (© 2011 American Association of Blood Banks.)
- Published
- 2012
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14. Do diluents interfere with the determination of platelet count in platelet concentrates?
- Author
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Ringwald J, Friedhoff H, Weiss D, Eckstein R, and Antoon M
- Subjects
- Humans, Blood Platelets cytology, Platelet Count methods, Platelet Count standards
- Published
- 2010
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15. Do platelets stored in additive solution really show limited osmotic balance?
- Author
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Ringwald J, Krex D, Weiss D, Hendelmeier M, Zingsem J, and Eckstein R
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- Humans, Osmotic Pressure, Solutions, Blood Platelets, Blood Preservation methods
- Published
- 2009
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16. Automated CD14+ monocyte collection with the autoMNC program of the COM.TEC cell separator.
- Author
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Strasser EF, Schremmer M, Hendelmeier M, Weiss D, Ringwald J, Zimmermann R, Weisbach V, Zingsem J, and Eckstein R
- Subjects
- Cell Separation instrumentation, Dendritic Cells immunology, Humans, Leukapheresis instrumentation, Leukocyte Count, Leukocytes, Mononuclear immunology, Reproducibility of Results, Software, Cell Separation methods, Dendritic Cells cytology, Leukapheresis methods, Leukocytes, Mononuclear cytology, Lipopolysaccharide Receptors analysis
- Abstract
Background: The standard mononuclear cell (MNC) program of the COM.TEC device (Fresenius HemoCare GmbH) showed excellent collection efficiency of CD14+ monocytes. A major disadvantage was high content of residual cells in MNC harvests, which could influence dendritic cell (DC) culture., Study Design and Methods: The autoMNC program (COM.TEC) was compared with the standard MNC program (n = 12). Additionally, two cycle volumes (300 mL vs. 450 mL, n = 19) were compared (standard MNC program). Samples were assayed for white blood cells (WBCs), red blood cells (RBCs), granulocytes (PMNs), hematocrit, and platelets (PLTs) on an automated blood cell counter (Sysmex K 4500, TAO Medical). CD14+ cells were analyzed by flow cytometry (FACSCalibur, BD)., Results: The autoMNC program produced 1.33 x 10(9) +/- 0.36 x 10(9) CD14+ cells, 5.60 x 10(11) +/- 0.97 x 10(11) PLTs, and 1.43 x 10(11) +/- 0.37 x 10(11) RBCs. Compared to the standard MNC program, significantly higher PLT yields but lower RBC yields and product volume were harvested. Increasing the CV from 300 to 450 mL dropped the product volume, residual PLTs, and RBCs significantly, whereas WBC and monocyte yields did not change. The WBC predonation counts of donors correlated significantly with monocyte yields., Conclusions: The autoMNC program reduced the buffy coat (BC) volume and RBC yields in products compared to the standard MNC program. Increasing the CV (standard MNC program) reduced residual PLTs, RBCs, and the BC volume of MNC harvests. The donor WBC predonation count was a good predictor for the monocyte yield of products.
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- 2007
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17. Recovery of white blood cells and platelets from leukoreduction system chambers of Trima Accel and COBE Spectra plateletpheresis devices.
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Strasser EF, Weidinger T, Zimmermann R, Ringwald J, and Eckstein R
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- Antigens, CD blood, Blood Component Removal methods, Humans, Blood Platelets cytology, Dendritic Cells cytology, Leukocyte Reduction Procedures methods, Leukocytes, Mononuclear cytology
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- 2007
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18. Effect of gamma irradiation with 30 Gy on the coagulation system in leukoreduced fresh-frozen plasma.
- Author
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Weisbach V, Strobel J, Hahn B, Rödel F, Lotter M, Zingsem J, Ringwald J, and Eckstein R
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- ABO Blood-Group System, Biomarkers, Cell Separation, Dose-Response Relationship, Radiation, Hemostasis radiation effects, Humans, Blood Coagulation radiation effects, Leukocytes, Plasma radiation effects, Ultraviolet Rays
- Abstract
Background: The aim of this study was to investigate the effect of gamma irradiation with 30 Gy on the coagulation system in leukoreduced fresh-frozen plasma (FFP)., Study Design and Methods: In 74 FFP units that had been stored for 352 +/- 103 days below -30 degrees C, the following variables were determined in parallel in an irradiated and not irradiated half: prothrombin time (PT); activated partial thromboplastin time (APTT); thrombin time; antithrombin III; protein C; protein S; von Willebrand factor antigen; ristocetin cofactor; plasminogen-alpha(2)-antiplasmin; the coagulation factors fibrinogen, factor (F)II, FV, FVII, VIII, F IX, FX, FXI, FXII, FXIII, and activated factor XII (FXIIa); D-dimer; fibrin monomer; thrombin-antithrombin complex; prothrombin fragment 1 + 2 (F1+2); plasmin-alpha(2)-antiplasmin complexes (PAPs); and platelet factor 4. The FVII activity ratio was assayed to quantify activation of FVII., Results: Irradiation with 30 Gy resulted in a reduction of APTT (35.0 +/- 4.1 sec vs. 34.4 +/- 4.1 sec; p = 0.00000006) and PT (89.8 +/- 8.2% vs. 90.7 +/- 8.0%; p = 0.002) and a significant increase of the activities of the coagulation factors FII, FV, FVII, F IX, FX, and FXII. FVIII activity decreased from 118 +/- 31 to 116 +/- 32 percent (p = 0.02). Activation of the coagulation system was shown by an increase in the FVII activity ratio (1.19 +/- 0.29 vs. 1.31 +/- 0.34; p = 0.0000001), FXIIa (0.81 +/- 0.50 ng/mL vs. 0.90 +/- 0.51 ng/mL; p = 0.006), and F1+2 (1.19 +/- 0.20 nmol/L vs. 1.24 +/- 0.20 nmol/L; p = 0.000005) after irradiation with 30 Gy, whereas an increase of PAP (16.2 +/- 11.5 ng/mL vs. 20.2 +/- 12.0 ng/mL; p = 0.0004) demonstrated activation of the fibrinolytic system. No negative influence of irradiation with 30 Gy on inhibitors of coagulation was observed., Conclusion: Gamma irradiation of leukoreduced FFPs with 30 Gy results in a significant but very weak activation of the coagulation and fibrinolytic system in FFPs.
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- 2007
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19. Short-term liquid storage of CD14+ monocytes, CD11c+, and CD123+ precursor dendritic cells produced by leukocytapheresis.
- Author
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Strasser EF, Keller B, Hendelmeier M, Ringwald J, Zingsem J, and Eckstein R
- Subjects
- CD11c Antigen, Glucose analysis, Humans, Hydrogen-Ion Concentration, Interleukin-3 Receptor alpha Subunit, Leukocyte Count, Lipopolysaccharide Receptors, Polyenes, Polyvinyl Chloride, Prospective Studies, Antigens, CD analysis, Blood Preservation, Dendritic Cells, Leukapheresis, Monocytes
- Abstract
Background: This prospective study compared white blood cell (WBC) storage in polyvinylchloride (PVC) bags and in polyolefin (POF) bags. After leukapheresis, CD14+ monocytes, CD11c+, and CD123+ precusor dendritic cells (DCs) were analyzed under platelet (PLT) storage conditions., Study Design and Methods: Twenty-five leukapheresis procedures were performed on blood cell separators (AS.TEC204 [PVC; Fresenius HemoCare GmbH] and the COBE Spectra [POF, Gambro BCT]). Blood cell counts, glucose, lactic acid, pO(2), pCO(2), and pH were measured in mononuclear cell (MNC) harvests on Days 0, 1, 3, and 5. WBCs were analyzed by flow cytometry., Results: The WBC yields of the AS.TEC204 harvests were 25 percent higher (13.4 x 10(9) +/- 2.7 x 10(9) WBCs) compared to the COBE Spectra (9.9 x 10(9) +/- 2.5 x 10(9) WBCs). During 5-day storage, WBC counts (PVC bags) decreased significantly (24%). Storage in POF bags showed more consistent results (WBC loss, 6%). Loss of CD14+ monocytes and CD11c+ precursor DCs did not differ significantly in leukapheresis products. CD123+ precursor DCs stored in PVC bags dropped by more than 90 percent (POF bags, 24%). Lactic acid concentrations exceeded 20 mmol per L after 24 hours in PVC bags and after 72 hours in POF bags. The mean pH value on Day 5 was 6.2 (PVC) and 6.3 (POF). On Day 1, the product glucose concentration decreased by 76 percent after storage in PVC bags and by 16 percent in POF bags., Conclusions: Storage of MNCs within 72 hours in the original harvest container assures stable WBC content and is easy to perform. POF bags should be preferred in the case of extended WBC storage. Patient studies should clarify changes in efficiency of hematopoietic reconstitution that might occur over time during MNC storage.
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- 2007
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20. Evaluation of a new apheresis system for the collection of leukoreduced single-donor platelets.
- Author
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Zingsem J, Strasser E, Ringwald J, Zimmermann R, Weisbach V, and Eckstein R
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- Humans, Leukocyte Reduction Procedures standards, Plateletpheresis standards, Blood Donors, Blood Platelets cytology, Leukocyte Reduction Procedures instrumentation, Plateletpheresis instrumentation
- Abstract
Background: The Fresenius COM.TEC cell separator is a new device for producing white cell concentrates (WBCs) and leukoreduced single-donor platelet concentrates (SDPs) and performing therapeutic cytapheresis and plasmapheresis that might replace the Fresenius systems AS104 and AS.TEC 204. This novel system's performance was evaluated for producing leukoreduced SDPs., Study Design and Methods: In an investigational phase, each of 200 donors underwent plateletpheresis with the AS.TEC 204 and the COM.TEC systems. The collection efficiency (CE) and WBC contamination of the different techniques were compared. After some hard- and software modifications, the system was evaluated in an additional 800 procedures in the confirmatory phase., Results: In the investigational phase, the CE of the COM.TEC device was increased significantly in comparison to the AS.TEC 204 device's CE (by 45 +/- 32% when collecting 1 unit of platelets [PLTs] and 1 unit of fresh-frozen plasma and by 43 +/- 42% when collecting only 1 unit of PLTs). Although all AS.TEC products proved to be leukoreduced, 2 percent of the COM.TEC procedures led to PLT concentrates containing more than 1 x 10(6) WBCs. In the confirmatory phase, all 1300 products from 800 COM.TEC procedures proved to be leukoreduced. Furthermore, the CE increased significantly from 53.5 +/- 4.6 percent in the investigational phase to 55.5 +/- 4.9 percent (p < 0.001) in the confirmatory phase., Conclusions: These data suggest that the new COM.TEC system offers a significantly and importantly improved CE in plateletpheresis procedures in comparison to the AS.TEC system. In the final version, the PLT products collected with this system fulfill the most stringent criteria for leukoreduced PLTs. This aim was achieved without additional filtration steps and thus without filtration-related PLT loss.
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- 2007
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21. Impact of different hold time before addition of platelet additive solution on the in vitro quality of apheresis platelets.
- Author
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Ringwald J, Haager B, Krex D, Zimmermann R, Strasser E, Antoon M, De Schrijver E, and Eckstein R
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- Glucose metabolism, Humans, Hydrogen-Ion Concentration, Lactic Acid analysis, Osmotic Pressure, P-Selectin analysis, Time Factors, Transforming Growth Factor beta analysis, Transforming Growth Factor beta1, Blood Platelets drug effects, Blood Preservation methods, Plateletpheresis standards, Solutions pharmacology
- Abstract
Background: The quality of platelets (PLTs) stored in PLT additive solution (PAS) is dependent on the type and proportion of the used PAS. No data are available as to whether a different hold time before the addition of PAS to hyperconcentrated PLT suspensions has an impact on PLT quality. The in vitro quality between single-donor PLT concentrates was compared with two different hold times with two PASs., Study Design and Methods: On two occasions, 6x10(11) PLTs in 150 mL of plasma were collected from 20 blood donors. The units were split into two equal parts, and 140 mL of PAS-II or PAS-IIIM (randomized sequence) was added after 2 or 8 hours resulting in a PAS proportion of 65 percent. On Days 1, 5, and 7, glucose and lactate concentration, pH value, PLTs' P-selectin expression, response to hypotonic shock, and release of transforming growth factor-beta1 were determined., Results: On all days, the lactate concentrations were higher and pH values were lower in units with an 8-hour hold time, whereas the results of in vitro tests relating to the in vivo viability and activation of PLTs were similar for both groups. PAS-IIIM-stored PLTs showed a lower glycolytic activity and better results in all performed in vitro tests than PAS-II-stored PLTs., Conclusions: Although the metabolism of glucose was enhanced during hold time, the differences between both hold time groups are not meaningful from a biological viewpoint. Therefore, an 8-hour hold time is feasible. PLT storage in PAS-IIIM results in a PLT in vitro quality superior to that of PLTs stored in PAS-II.
- Published
- 2006
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22. Measuring the pH of platelet concentrates.
- Author
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Ringwald J, Zimmermann R, Strasser E, Weiss D, and Eckstein R
- Subjects
- Humans, Hydrogen-Ion Concentration, Plateletpheresis, Reproducibility of Results, Blood Platelets, Blood Preservation, Quality Control
- Published
- 2006
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23. Platelet function in variable platelet split products intended for neonatal transfusion.
- Author
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Strasser EF, Stachel DK, Schwarzkopf P, Ringwald J, Weisbach V, Zimmermann R, Zingsem J, and Eckstein R
- Subjects
- Adult, Blood Preservation, Female, Humans, Hydrogen-Ion Concentration, Infant, Newborn, Male, Platelet Count, Platelet Transfusion, Plateletpheresis, Reproducibility of Results, Time Factors, Blood Platelets chemistry, Lactic Acid analysis, P-Selectin analysis, Platelet-Derived Growth Factor analysis, beta-Thromboglobulin analysis
- Abstract
Background: Only a few systematic studies have examined the effect of variable produced small platelet (PLT) aliquots on PLT function before transfusion to neonates. Although neonatal transfusion could be critical, no standardization of production or systematic quality controls have been introduced so far., Study Design and Methods: PLT split products were prepared in three different ways (30- or 60-mL bag, syringe aliquot) at different times from the parent unit (Days 1-4) and stored for 2 or 4 hours. The measures of PLT function include pH, lactate, P-selectin expression, and cytokines (beta-thromboglobulin [beta-TG], PLT-derived growth factor AB [PDGF-AB]). Additionally, syringe passage (0.5 mL/min) was assessed., Results: High product variability of PLT content was found (40% deviation of PLT content from programmed target, 13%-19% PLT loss by product distribution), which resulted in PLT concentrations of split units between 0.94 x 10(9) and 1.66 x 10(9) PLTs per mL. Different gas transfer rates (pCO2) of PLT containers caused different pH values of the product (Trima 7.47 +/- 0.09 vs. COM.TEC 7.33 +/- 0.08; p < 0.0001), but acceptable results of PLT metabolism were found in all split units (minimum pH, 7.09; maximum lactate content, 13.1 mmol/L). P-selectin expression on PLTs increased by factor of 2 in the parent units stored for 4 days (16.9 +/- 8.6% 32.2 +/- 13.4%; p = 0.02). After Day 3, beta-TG and PDGF-AB increased by twofold. PLTs stored during passage for 100 minutes in syringes dropped pO(2) by 50 percent and caused 15 percent higher lactate levels., Conclusion: High variability of PLT content in split units requires at least additional PLT counts before transfusion in critical preterm or neonatal infants.
- Published
- 2006
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24. Washing platelets with new additive solutions: aspects on the in vitro quality after 48 hours of storage.
- Author
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Ringwald J, Althoff F, Zimmermann R, Strasser E, Weisbach V, Zingsem J, and Eckstein R
- Subjects
- Blood Platelets metabolism, Humans, Hydrogen-Ion Concentration, In Vitro Techniques, Osmotic Pressure, P-Selectin metabolism, Platelet Activation, Plateletpheresis, Blood Platelets cytology, Blood Preservation methods, Cryopreservation methods, Organ Preservation Solutions
- Abstract
Background: Rare clinical conditions cause the need for washed platelet (PLT) concentrates (PCs). Saline-washed PCs can only be stored shortly, however, owing to lack of substrates for PLT metabolism. New PLT additive solutions (PASs) contain such substrates and might be used alternatively. The in vitro quality of apheresis PCs washed with Composol-PS or modified PAS-III (PAS-IIIM) stored up to 48 hours after wash was compared., Study Design and Methods: Twelve blood donors underwent two apheresis procedures (A and B) collecting 6.0 x 10(11) PLTs in 500 mL of plasma with a least 2 weeks in between. The PCs collected by Apheresis A were stored for 3 days and then split in two equal units before washing with Composol-PS or PAS-IIIM. The PCs collected by Apheresis B were split after collection. One unit was released for transfusion and 1 unit was stored unwashed up to Day 6 and used as reference unit. In vitro testing was performed before and after washing as well as 24 and 48 hours after wash., Results: After 48 hours of postwash storage, the units washed with either PAS showed acceptable results for hypotonic shock response (HSR), P-selectin expression, and pH, whereas PLT aggregability was significantly impaired. Throughout the storage, unwashed units showed better in vitro quality. HSR and P-selectin expression were similar before and immediately after the washing procedure., Conclusion: Based on these in vitro results, 48-hour postwash storage of washed PCs with the two PASs seems to be feasible. In vivo recovery studies, however, must confirm this finding in the future.
- Published
- 2006
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25. Frequently used plateletpheresis techniques result in variable target yields and platelet recruitment of donors.
- Author
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Strasser EF, Schuster M, Egler K, Bauer J, Weisbach V, Ringwald J, Zimmermann R, Zingsem J, and Eckstein R
- Subjects
- Adult, Blood Component Removal instrumentation, Blood Component Removal methods, Female, Humans, Male, Needles, Platelet Count, Prospective Studies, Sex Factors, Time Factors, Volunteers, Blood Donors psychology, Plateletpheresis instrumentation, Plateletpheresis methods, Software
- Abstract
Background: Standard plateletpheresis techniques and effects on platelet (PLT) donors were investigated to provide an informative basis for advancement of apheresis software., Study Design and Methods: Three paired groups with 33 male and 22 female blood donors were prospectively investigated by analyzing blood counts of donors and products. Four apheresis platforms, the COBE Spectra LRS and the Trima v4 (Gambro BCT) and the AS.TEC204 and the COM.TEC (Fresenius Hemocare), were compared. Deviations of the collected from programmed PLT targets and donor PLT recruitment were calculated for single-unit PLT concentrates (SU-PCs; 3 x 10(11) PLTs) and double-unit PLT concentrates (DU-PCs; 6 x 10(11) PLTs)., Results: Regarding SU-PCs, the productivity of the COM.TEC machine was superior to the AS.TEC204 machine, because of shorter processing time (54 min vs. 67 min) and higher yields (2.90 x 10(11) PLTs vs. 2.75 x 10(11) PLTs). Compared to the Spectra machine, the Trima v4 machine showed higher collection efficiencies (CEs) and shorter processing time and complied better with the programmed target (SU-PCs, 3.24 x 10(11) PLTs vs. 3.70 x 10(11) PLTs; DU-PCs, 6.87 x 10(11) PLTs vs. 7.56 x 10(11) PLTs). Harvests of the Spectra machine (DU-PCs) exceeded the target by 40 percent, which resulted in high PLT loss for donors. A longer processing time resulted in some higher CEs (SU-PCs, 53%; DU-PCs, 58%), which could contribute to this result. PLT recruitment compensated PLT loss to some extent., Conclusion: The major finding was that the newer devices (COM.TEC and Trima) gave more predictable yields than the older devices (AS.TEC204 and Spectra) and resulted in lower PLT deficit. PLT software should be improved to minimize relevant variations of collected yields regarding the programmed target.
- Published
- 2005
- Full Text
- View/download PDF
26. Plateletpheresis does not cause long-standing platelet-derived growth factor release into the donor blood.
- Author
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Zimmermann R, Loew D, Weisbach V, Strasser E, Ringwald J, Zingsem J, and Eckstein R
- Subjects
- Humans, Platelet Activation, Platelet Aggregation, Time Factors, Transforming Growth Factor beta blood, Transforming Growth Factor beta1, beta-Thromboglobulin metabolism, Blood Donors, Platelet-Derived Growth Factor metabolism, Plateletpheresis methods
- Abstract
Background: Recently, long-standing elevations of soluble growth factors released from platelets (PLTs) after contact with artificial surfaces during dialysis were described. They could be jointly responsible for the high frequency of death from cardiovascular diseases in dialysis patients. There are no comparable data on the extent and the duration of a growth factor release by plateletpheresis procedures., Study Design and Methods: A total of 37 plateletpheresis procedures were performed with two different devices. PLT-derived growth factor (PDGF) isoform AB, transforming growth factor (TGF)-beta1, and beta-thromboglobulin (beta-TG) were measured in the donors' plasma samples, and PLT activation and function were measured by cytometry and aggregometry before and after plateletpheresis and 1 and 24 hours later., Results: Before apheresis, the following mean plasma levels were found: beta-TG, 98.6 +/- 37.3 IU per mL; PDGF-AB, 71.5 +/- 38.5 pg per mL; and TGF-beta1, 2.24 +/- 0.80 ng per mL. At the end of the apheresis procedures, the mean PDGF-AB level had increased by a factor of 1.8 (p < 0.05). One hour later, the mean PDGF-AB level had normalized again. No significant change in the levels of beta-TG and TGF-beta1 was found by the apheresis procedures. There was no influence of the blood cell separator type on the results., Conclusion: Only a slight and rapidly reversible increase in soluble PDGF-AB was found during plateletpheresis and no increase in soluble TGF-beta1 and beta-TG was found. This change should not be harmful to the donor.
- Published
- 2005
- Full Text
- View/download PDF
27. Mononuclear cell variability and recruitment in non-cytokine-stimulated donors after serial 10-liter leukapheresis procedures.
- Author
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Strasser EF, Zimmermann R, Weisbach V, Ringwald J, Zingsem J, and Eckstein R
- Subjects
- Adult, Follow-Up Studies, Humans, Leukocyte Count, Lymphocyte Subsets cytology, Male, Middle Aged, Platelet Count, Prospective Studies, Leukapheresis instrumentation, Leukapheresis methods, Leukocytes, Mononuclear cytology
- Abstract
Background: We introduced monitoring of mononuclear cell (MNC) counts to obtain enhanced donor control and a stable quality of MNC products, because there are limited data available about blood donors after serial leukapheresis (LP) procedures., Study Design and Methods: In a prospective paired study, 13 male healthy blood donors underwent 10-L LP procedures performed on two apheresis devices by use of two MNC program settings (COBE Spectra, Gambro BCT, SF 250 vs. SF 500; and AS.TEC 204, Fresenius Hemocare, CP 129 vs. CP 194). Donors' pre- and postdonation MNC counts were analyzed by fluorescence-activated cell sorting., Results: After each 10-L LP procedure, a transient decline (p < 0.05) of CD14+ monocyte and platelet counts appeared in donors. Loss of donors' CD3+ T cells, CD19+ B cells, and CD16+56+ natural killer (NK) cells during MNC collection was partly compensated by cell recruitment. The MNC recruitment factor (RF) seems to be higher with high-yield MNC program settings. Negative correlations (p < 0.01) were noticed between predonation counts and RFs of CD3+ T cells and CD16+56+ NK cells. Four serial 10-L LP procedures did not result in long lasting MNC depletion for donors., Conclusion: MNC recruitment seems to depend on MNC program settings and collected cell yields. Low MNC counts could result in high cell recruitment that may contribute to stable collection results to some degree. Nevertheless, there seems to be a considerable individual variation of MNC recruitment in donors that should be investigated in more detail.
- Published
- 2005
- Full Text
- View/download PDF
28. Comparison of two mononuclear cell program settings on two apheresis devices intended to collect high yields of CD14+ and CD3+ cells.
- Author
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Strasser EF, Dittrich S, Weisbach V, Zimmermann R, Ringwald J, Achenbach S, Zingsem J, and Eckstein R
- Subjects
- Adult, Blood Cell Count, Hematocrit, Humans, Middle Aged, Prospective Studies, CD3 Complex analysis, Leukapheresis instrumentation, Lipopolysaccharide Receptors analysis, Monocytes cytology, T-Lymphocyte Subsets cytology
- Abstract
Background: In cancer and transplantation therapy apheresis devices and software of optimum standards are required for the collection of high cell yields with high purity of the desired cell fraction., Study Design and Methods: In a paired study, 15 healthy blood donors underwent four 10-L leukapheresis procedures (197 +/- 33 min) with an inlet blood flow rate of 60 mL per minute by use of two different MNC program settings of the COBE Spectra (Gambro BCT) and the AS.TEC 204 (Fresenius Hemocare) cell separators., Results: Use of the standard MNC program of both apheresis devices resulted in significantly higher (p < 0.01) collection efficiencies of CD14+ monocytes, CD3+ cells, CD4+ cells, CD8+ T cells, CD16+ CD56+ natural killer (NK) cells, and residual PLTs (p < 0.001), owing to higher centrifuge speed. The mean MNC purity of all components was more than 90 percent. By use of standard programs of either device, significant correlations (p < 0.01) between donor monocytes and preleukapheresis NK cell counts and the corresponding component cell yields were found., Conclusion: Compared to the program modifications with lower centrifuge velocities the standard MNC programs were significantly more efficient regarding CD14+, CD3+, and CD16+ CD56+ cells. Enhanced centrifuge speed and inlet blood flow rate in MNC programs resulted in higher, similar composed MNC concentrations of the products.
- Published
- 2004
- Full Text
- View/download PDF
29. Comparison of two apheresis systems for the collection of CD14+ cells intended to be used in dendritic cell culture.
- Author
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Strasser EF, Berger TG, Weisbach V, Zimmermann R, Ringwald J, Schuler-Thurner B, Zingsem J, and Eckstein R
- Subjects
- Adult, Aged, Cell Culture Techniques, Cell Separation methods, Erythrocyte Count, Female, Humans, Leukocyte Count, Male, Melanoma blood, Melanoma secondary, Middle Aged, Monocytes cytology, Platelet Count, Software, Blood Component Removal methods, Dendritic Cells chemistry, Dendritic Cells cytology, Lipopolysaccharide Receptors analysis
- Abstract
Background: Monocytes collected by leukapheresis are increasingly used for dendritic cell (DC) culture in cell factories suitable for DC vaccination in cancer., Study Design and Methods: Using modified MNC programs on two apheresis systems (Cobe Spectra and Fresenius AS.TEC204), leukapheresis components collected from 84 patients with metastatic malignant melanoma and from 31 healthy male donors were investigated. MNCs, monocytes, RBCs, and platelets (PLTs) in donors and components were analyzed by cell counters, WBC differential counts, and flow cytometry., Results: In 5-L collections, Astec showed better results regarding monocyte collection rates (11.0 vs. 7.4 x 10(6)/min, p = 0.04) and efficiencies (collection efficiency, 51.9 vs. 31.9%; p < 0.001). Both devices resulted in monocyte yields at an average of 1 x 10(9) (donors) and 2.5 x 10(9) (patients), whereas Astec components contained high residual RBCs. Compared to components with low residual PLTs, high PLT concentration resulted in higher monocyte loss (48 vs. 20%, p < 0.0001) before DC culture., Conclusion: The Astec is more efficient in 5-L MNC collections compared to the Spectra. Components with high residual PLTs result in high MNC loss by purification procedures. Thus, optimizing MNC programs is essential to obtain components with high MNC yields and low residual cells as prerequisite for high DC yields.
- Published
- 2003
- Full Text
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30. Cord blood processing with an automated and functionally closed system.
- Author
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Zingsem J, Strasser E, Weisbach V, Zimmermann R, Ringwald J, Goecke T, Beckmann MW, and Eckstein R
- Subjects
- Antigens, CD34 analysis, Cell Separation instrumentation, Humans, Microcomputers, Blood Specimen Collection methods, Cell Separation methods, Fetal Blood
- Abstract
Background: Umbilical cord blood processing with standard centrifugation techniques is performed in open systems and results in varying cell and volume recoveries., Study Design and Methods: Forty umbilical cord blood donations were randomly assigned to processing either with a microprocessor-controlled cell separator equipped with closed disposables or with a manual separation procedure in blood bags. The collection efficiency of nucleated cells, MNCs, RBCs, and CD34+ cells and the processing time were analyzed., Results: Using the cell processor, mean collection efficiencies were 78.6 +/- 24.9 percent for nucleated cells, 77.4 +/- 27.8 percent for MNCs, 55.5 +/- 14.6 percent for RBCs, and 83.6 +/- 32.5 percent for CD34+ cells, while they were 73.1 +/- 13.2 percent for nucleated cells, 78.1 +/- 14.9 percent for MNCs, 26.0 +/- 12.2 percent for RBCs, and 77.0 +/- 17.6 percent for CD34+ cells when using the standard centrifugation technique. The processing time was about 20 minutes for automated processing and 60 to 80 minutes for the standard centrifugation technique., Conclusion: Using the new cell processor, the collection efficiencies for nucleated cells, MNCs, and CD34+ cells are similar to those obtained by established centrifugation techniques while the RBC reduction is less effective. The main advantages of the new systems are the closed system, the more standardized processing procedure, and a significantly shorter processing time.
- Published
- 2003
- Full Text
- View/download PDF
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