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Jürgen Zingsem

Publications and source records attributed to Jürgen Zingsem.

13 recordsLinked to original sources
PubMed2006

CD 14+ cell collection in non-cytokine-stimulated donors with the COM.TEC cell separator.

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.

Blood Donors↗
PubMed2006

Washing platelets with new additive solutions: aspects on the in vitro quality after 48 hours of storage.

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.

Blood Platelets↗
PubMed2006

Platelet function in variable platelet split products intended for neonatal transfusion.

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.

Adult↗
PubMed2006

A pilot study of continuous ambulatory monitoring of blood pressure in repeated preoperative autologous blood donation.

BACKGROUND: The aim of this study was to investigate the occurrence of hypotension in the 24-hour period after preoperative autologous blood donation (PABD) in patients with and without hypertension. STUDY DESIGN AND METHODS: In 20 patients, 24-hour ambulatory blood pressure monitoring (ABPM) was performed before PABD was started and on every donation day in two repeated phlebotomies. RESULTS: Seven patients had no hypertension and 11 patients had hypertension. In 2 additional patients, hypertension was diagnosed during the study. Overall, the mean systolic BP (SBP) decreased from 131+/-15 mmHg before donation to 128+/-13 and 127+/-10 mmHg after Donations 1 and 2; the corresponding values for the diastolic BP (DBP) were 77+/-9, 75+/-9, and 73+/-7 mmHg, both without significant differences between the groups with and without hypertension. In single patients, substantial decreases of BP occurred, especially during the night. Two patients with and 2 without hypertension showed a nightly decrease in SBP and DBP of more than 10 percent (in 1 of these patients, more than 20%). Concerning diurnal BP variability, 1 patient with and 1 without hypertension, the latter showing a nightly decrease of SBP and DBP of more than 10 percent, also changed to the pattern of a nightly "extreme dipper" after PABD. CONCLUSION: In 25 percent of the patients, changes of BP were observed during the 24-hour period after PABD, especially during the night, which are known to be associated with an increased risk of cerebral or myocardial ischemia. Whether those changes of BP lead to major morbidity or mortality requires further investigation.

Adult↗
PubMed2005

Mononuclear cell variability and recruitment in non-cytokine-stimulated donors after serial 10-liter leukapheresis procedures.

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.

Adult↗
PubMed2005

Frequently used plateletpheresis techniques result in variable target yields and platelet recruitment of donors.

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.

Adult↗
PubMed2004

Comparison of two mononuclear cell program settings on two apheresis devices intended to collect high yields of CD14+ and CD3+ cells.

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.

Adult↗
PubMed2003

In vitro quality control of red blood cell concentrates outdated in clinical practice.

The properties of red blood cell (RBC) concentrates stored in different additive solutions have been previously examined under laboratory conditions at the end of shelf-life. However, whether these data are representative for RBC units used in clinical practice has not been shown. Therefore, we examined 164 RBC units from six manufacturers outdated after clinical usage in a hospital-based transfusion service for cellular content, hemolysis, adenosin triphosphate, 2,3-DPG, pH, oxygen saturation and levels of beta-thromboglobulin and proinflammatory cytokines interleukin (IL) 1beta (IL-1), IL-6, IL-8 and tumor necrosis factor alpha (TNFalpha). Results were correlated with the number of interruptions of recommended storage conditions and with different manufacturers. TNFalpha and IL-8 levels in the supernatant of RBC concentrates showed a weak correlation with the number of interruptions of recommended storage conditions (TNFalpha: r = 0.25, P < 0.01; IL-8: r = 0.20, P < 0.01) for the whole series. We detected no significant correlation between hemolysis and interruptions of recommended storage conditions or any of the remaining studied parameters. However, we found significant differences between RBC concentrates supplied by different manufacturers with respect to cellular content and most of the studied parameters. RBC concentrates containing SAG-M from one single manufacturer had higher in vitro hemolysis at the end of shelf-life compared to all other manufacturers (P < 0.05). We conclude from our data that interruptions of optimal conditions for storage of red cell components during cross-match testing and transport in our setting play a minor role for in vitro properties of RBC units at the end of shelf-life. The influence of processes of production, storage and/or transport until entry of RBC units into our blood component depot seems to be much more important for final product quality at the end of shelf-life than subsequent events.

Blood Preservation↗
PubMed2003

Cord blood processing with an automated and functionally closed system.

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.

Antigens, CD34↗
PubMed2003

Collection of WBC-reduced single-donor PLT concentrates with a new blood cell separator: results of a multicenter study.

BACKGROUND: A new cell separator (COM.TEC, Fresenius) was recently developed aimed at efficient collection of WBC-reduced single-donor PLT concentrates (SDPs). STUDY DESIGN AND METHODS: Five German centers collected 554 WBC-reduced SDPs with help of the COM.TEC cell separator. Two multicenter cell counting studies were performed at the beginning and at the end of the study to document uniform counting results among the participating centers. RESULTS: A total of 441 (79.6%) PLT collections were included in the study according to the protocol. A total of 342 single-dose and 99 double-dose SDPs were collected. For single-dose SDPs, an average blood volume of 2826 +/- 409 mL was processed in a donation time of 55 +/- 11 minutes. Mean PLT yield of these products was 3.11 x 1011+/- 0.40 x 1011 and the WBC contamination was 0.11 x 106+/- 0.20 x 106. For double-dose SDPs (PLT count, 5.29 +/- 0.93 x 1011), 3943 +/- 639 mL was processed. The average difference between the target and the collected PLT concentration was -2.8 +/- 12.0 percent for single-dose SDPs and -1.8 +/- 9.5 for double-dose SDPs, respectively. The collection efficiency was 53.7 +/- 5.8 percent for single-dose SDPs and 58.2 +/- 6.2 percent for double-dose SDPs. If all results of each sample from the counting study were set to unity (to the mean over all centers), most PLT determinations were very similar to the mean, for example, near or 1 if set to unity. CONCLUSION: The COM.TEC machine makes it possible to obtain WBC-reduced SDPs that comply with current standards.

Blood Cell Count↗
PubMed2003

Comparison of two apheresis systems for the collection of CD14+ cells intended to be used in dendritic cell culture.

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.

Adult↗
PubMed2002

Preparation of FFP as a by-product of plateletpheresis.

BACKGROUND: To reduce the production costs of single-donor platelets (SDPs), a study was conducted to investigate whether plasma collected as a by-product of plateletpheresis satisfies the quality requirements for FFP without impairing the quality of the SDP component. STUDY DESIGN AND METHODS: Ninety-two donors with platelet (PLT) counts <270 x 10(9) per L underwent plateletpheresis using an automated cell separator (Spectra Apheresis System with the Leukoreduction System [LRS], Gambro BCT, Lakewood, CO). The machine was programmed to collect 3 x 10(11) PLTs in 250 mL of plasma with an additional unit of 350 mL of plasma or 3 x 10(11) PLTs in 250 mL of plasma without additional plasma in 10 procedures. FV and FVIII and residual RBCs, WBCs, and PLTs in the plasma were measured for quality control. RESULTS: FV was 0.87 +/- 0.18 IU per mL, and FVIII was 1.32 +/- 0.48 IU per mL in the plasma components (n = 41). The recovery was 94.1 +/- 5.5 percent for FV and 102.2 +/- 9.5 percent for FVIII when compared with the donors' predonation values. Residual cells were 0.002 +/- 0.009 x 10(9) RBCs per L (n = 30), 12 +/- 6 x 10(9) PLTs per L (n = 30), and 0.32 +/- 0.37 x 10(6) WBCs per L (n = 92). CONCLUSIONS: Using the automated cell separator and special software, it is possible to collect plasma as a by-product of plateletpheresis that meets the properties requested for FFP without impairing the quality of the SDP components. The content of clotting factors is within the requested range for FFP. Residual cell counts are within all European and U.S. specifications for FFP, and the WBC content even satisfies the criteria for WBC-reduced blood components. The collection of FFP as a by-product does not cause any additional costs and thus helps to reduce the costs in preparing blood components.

Adult↗