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To compare the performance of seven currently available test systems in the detection of erythrocyte alloantibodies (ab), we tested in parallel 446 sera samples containing red cell ab [368 sera samples with ab that are assumed to be clinically significant (cs-ab) and 78 sera samples with ab that are assumed to be of minor clinical significance (ms-ab)] using the tube spin low-ionic-strength solution (addition method) indirect antiglobulin test (tube LISS-IAT), three microtube column agglutination techniques (DiaMed-ID, Ortho BioVue and Bio-Rad Scangel), one affinity adherence test system (CLB/Mast CellBind Screen) and two solid-phase tests [Biotest Solidscreen II and Immucor Capture-R Ready-Screen (4)]. To address the specificity of the three test systems under routine conditions, results of 4566 patient samples obtained using the tube LISS-IAT, results of 5205 patient samples obtained using the Scangel and results of 3560 samples obtained using the Capture-R were evaluated. The DiaMed-ID detected 344 cs-ab and 43 ms-ab, BioVue 333 cs-ab and 48 ms-ab, Scangel 348 cs-ab and 62 ms-ab, CellBind Screen 346 cs-ab and 47 ms-ab, Solidscreen 330 cs-ab and 38 ms-ab, Capture-R 358 cs-ab and 45 ms-ab and LISS-IAT 159 cs-ab and 12 ms-ab. In routine practice, erythrocyte cs-ab could be identified in 61 (67·8%) of 90 reactive sera (specificity: 98·6%) in the tube LISS-IAT, in 169 (58·7%) of 288 (94·4%) in Bio-Rad Scangel and in 101 (51·0%) of 198 reactive sera (94·3%) in Capture-R. We conclude that the sensitivity of the microcolumn, affinity adherence and solid-phase test systems in the detection of cs-ab was similar and was markedly superior to that of the conventional tube LISS-IAT. All high-sensitive test systems produced higher rates of false positives and ms-ab compared to the tube test. An individual cost–benefit analysis, considering the recent knowledge about the clinical significance of weak-reactive cs-ab, should be performed in every institution to decide whether and if so which high-sensitive screening system should be applied. [ABSTRACT FROM AUTHOR]

New platelet (PLT) additive solutions (PASs) allow a plasma carryover of< 30% in PLT concentrates. This implicates the need to collect apheresis PLT concentrates at very high PLT concentrations: so-called dry PLTs (DPs). We used the TRIMA, with software version 4 (TRIMA V4), to collect such DPs and investigated thein vitroquality of these PLTs when stored in the new modified PAS-III (PAS-IIIM).TRIMA V4 was programmed to collect 6·0 × 1011 PLTs at a concentration of 5000 × 103 PLTs/µl. Two DPs were pooled, split into four equal parts and diluted to obtain secondary pools (SPs) consisting of 70% PAS-III/30% plasma, 70% PAS-IIIM/30% plasma, 80% PAS-IIIM/20% plasma or 100% plasma.In vitrotesting was performed on days 0, 1, 5 and 7. Collection efficiency (CE), collection rate (CR) and PLT yield were calculated for each donation.Thirty-two runs with TRIMA V4 were performed, collecting 6·58 ± 0·74× 1011 PLTs at a concentration of 4255 ± 914 × 103/µl in 99 ± 19·9 min, resulting in a CE of 65·3 ± 8·2% and a CR of 6·92 ± 1·6 × 109 PLTs/min. On day 0, 34–37% of the PLTs in the units prepared for storage were already activated. PLTs stored in 70% or 80% PAS-IIIM showed superiorin vitroquality compared to PLTs stored in PAS-III.TRIMA V4 is a suitable device for the collection of DPs. Nevertheless, improvements are desirable to further increase the ability to concentrate PLTs at very high levels. The storage of apheresis-derived PLTs in PAS III-M is a very promising approach, even at a plasma carryover of< 30%. [ABSTRACT FROM AUTHOR]

Aside from new software the blood cell separator TRIMA (GambroBCT) also received a newly designed separation chamber offering a novel single stage separation technology, called Trima Accel. We evaluated this new system focusing on productivity and donor comfort by comparing it to the previous version (Trima version 4) in collecting single-donor platelet concentrates (SD-PCs) and plasma. Each of 20 donors underwent platelet apheresis using both devices. We compared the collection efficiency (CE), the collections rate (CR), the volume of the collected plasma and the residual leukocytes. Furthermore we compared donor comfort in terms of duration of the donation, flow of citrate back to the donor and platelet and whit blood cell (WBC) loss. While the number of collected platelets and the platelet concentration did not differ significantly between both techniques the time of the procedure was reduced by 15.6% with Trima Accel. This results in an increase of the CR and CE of 25% and 15% respectively when using Trima Accel. Log normal probability plotting of WBC counts showed that both techniques complied with the European and the US leukoreduction guidelines. The mean flow of ACDA to the donor perminute and per litre blood volume was also reduced by 20%. These data show that the Trima Accel represents a further improvement in apheresis platelet production with a better productivity and donor comfort, especially regarding the mean flow of ACDA to the donor. [ABSTRACT FROM AUTHOR]

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]