Clinical effectiveness of leucoreduced, pooled donor platelet concentrates, stored in plasma or additive solution with and without pathogen reduction.

Pathogen reduction (PR) of platelet products increases costs and available clinical studies are equivocal with respect to clinical and haemostatic effectiveness. We conducted a multicentre, open-label, randomized, non-inferiority trial comparing the clinical effectiveness of buffy-coat derived leukoreduced platelet concentrates (PC) stored for up to 7 d in plasma with platelets stored in platelet additive solution III (PASIII) without and with treatment with amotosalen-HCl/ultraviolet-A (UVA) photochemical pathogen reduction (PR-PASIII). Primary endpoint of the study was 1-h corrected count increment (CCI). Secondary endpoints were 24-h CCI, bleeding, transfusion requirement of red cells and PC, platelet transfusion interval and adverse transfusion reactions. Compared to plasma-PC, in the intention to treat analysis of 278 evaluable patients the mean difference for the 1-h CCI of PR-PASIII-PC and PASIII-PC was -31% (P < 0.0001) and -9% (P = n.s.), respectively. Twenty-seven patients (32%) had bleeding events in the PR-PASIII arm, as compared to 19 (19%) in the plasma arm and 14 (15%) in the PASIII arm (P = 0.034). Despite the potential advantages of pathogen (and leucocyte) inactivation of amotosalen-HCl/UVA-treated platelet products, their clinical efficacy is inferior to platelets stored in plasma, warranting a critical reappraisal of employing this technique for clinical use.

A single assay for multiple storage-sensitive red blood cell characteristics by means of infrared spectroscopy.

BACKGROUND: To maintain a high quality of red blood cells (RBCs), RBC characteristics must be followed during storage under blood bank conditions. By means of infrared (IR) spectroscopy, several characteristics can be measured simultaneously. STUDY DESIGN AND METHODS: IR spectra were acquired for samples from RBCs that were collected and stored according to Dutch blood bank procedures for a period of up to 50 days. Spectra of the soluble cell components were acquired separately after hypotonic lysis of the cells, followed by centrifugation. Characteristic vibrational bands were analyzed with respect to storage time-dependent changes in peak position and in intensity. RESULTS: A decrease in corresponding peak intensities indicates that RBCs lose protein and lipid during storage. Changes in protein secondary structure during storage are largely confined to integral membrane proteins and membrane-associated proteins. A concurrent decrease in lipid packing density probably reflects the gradual change in cellular shape from discoidal to globular. By integration over a narrow range, storage-dependent changes in intracellular adenosine triphosphate (ATP) and glucose levels could be estimated. ATP levels decrease during storage, but stay above the required 75% of the initial level after 35 days of storage. Glucose concentrations stay well above 5 mmol/L over the entire storage period. CONCLUSION: IR spectroscopy is a promising technique to follow structural and metabolic changes in RBCs during storage under blood bank conditions. Several variables can be determined rapidly in a single measurement.

Survival of red blood cells after transfusion: a comparison between red cells concentrates of different storage periods.

BACKGROUND: The use of fresh red blood cells (RBCs) is recommended for critically ill patients and patients undergoing surgery, although there is no conclusive evidence that this is beneficial. In this follow-up study, the short-term and the long-term recovery of irradiated, leukoreduced RBCs transfused after either a short storage (SS) or a long storage (LS) period were compared. By consecutive transfusion of RBCs with a SS and LS period, a direct comparison of their survival within the same patient was possible. STUDY DESIGN AND METHODS: Ten transfusion-requiring patients each received a SS RCCs (stored 0-10 days) and a LS RCCs (stored 25-35 days) consecutively. Short-term and long-term survival of the transfused RBCs was followed by flow cytometry using natural differences in RBC antigens between donors and patients. Posttransfusion recovery (PTR) was measured at several time points after transfusion. RESULTS: The mean 24-hour PTR of SS RBCs is 86.4 +/- 17.8 percent and that of LS RBCs 73.5 +/- 13.7 percent. After the first 24 hours, the mean times to reach a PTR of 50 percent of the 24-hour PTR (T50) and mean potential life spans (mPLs) of the surviving SS and LS RBCs (41 and 116 days and 41 and 114 days, respectively) do not differ. CONCLUSIONS: The mean 24-hour PTR of both SS and LS RBCs complies with the guidelines, even in a compromised patient population. The 24-hour PTR of SS RBCs, however, is significantly higher than that of LS RBCs. The remaining population of SS and LS RBCs has a nearly identical long-term survival. Therefore, depletion of the removal-prone RBCs before transfusion may be an efficient approach for product improvement.

Vesicles generated during storage of red cells are rich in the lipid raft marker stomatin.

BACKGROUND: The release of vesicles by red blood cells (RBCs) occurs in vivo and in vitro under various conditions. Vesiculation also takes place during RBC storage and results in the accumulation of vesicles in RBC units. The membrane protein composition of the storage-associated vesicles has not been studied in detail. The characterization of the vesicular membrane might hint at the underlying mechanism of the storage-associated changes in general and the vesiculation process in particular. STUDY DESIGN AND METHODS: Vesicles from RBCs that had been stored for various periods were isolated and RBCs of the same RBC units were used to generate calcium-induced microvesicles. These two vesicle types were compared with respect to their size with atomic force microscopy, their raft protein content with detergent-resistant membrane (DRM) analysis, and their thrombogenic potential and activity with annexin V binding and thrombin generation, respectively. RESULTS: The storage-associated vesicles and the calcium-induced microvesicles are similar in size, in thrombogenic activity, and in membrane protein composition. The major differences were the relative concentrations of the major integral DRM proteins. In storage-associated vesicles, stomatin is twofold enriched and flotillin-2 is threefold depleted. CONCLUSION: These data indicate that a stomatin-specific, raft-based process is involved in storage-associated vesiculation. A model of the vesiculation process in RBCs is proposed considering the raft-stabilizing properties of stomatin, the low storage temperature favoring raft aggregation, and the previously reported storage-associated changes in the cytoskeletal organization.

Red cell concentrates of hemochromatosis patients comply with the storage guidelines for transfusion purposes.

BACKGROUND: Therapeutic phlebotomy is the preferred treatment for iron overload associated with hemochromatosis. In the Netherlands, red blood cell concentrates (RCCs) from hemochromatosis patients are not used for transfusion purposes. In this study, their storage performance was compared with that of control donors as a first step in the evaluation of their potential usefulness for transfusion. STUDY DESIGN AND METHODS: RCCs were obtained from hemochromatosis patients and regular donors, either by apheresis or by whole-blood collection, and stored up to 50 days under routine Dutch blood bank conditions. Weekly samples were taken for determination of hematologic, biophysical, and biochemical variables. RESULTS: Most variables displayed the same storage-related changes in RCCs originating from hemochromatosis patients as in those from regular donors. In all RCCs, hemolysis remained well below the guideline limit of 0.8 percent for up to 6 weeks of storage, and the glucose concentration remained above the required 5 mmol per L up to 5 weeks of storage. After 4 weeks of storage, the mean ATP level remained above the required limit of 75 percent of the starting value in all RCCs as well. The major difference was a larger mean cell volume in hereditary hemochromatosis RBCs up to 50 days of storage. CONCLUSIONS: RCCs from hemochromatosis patients comply with the in vitro quality requirements for transfusion. This paves the way for the final step, namely, the establishment of the 24-hour RBC posttransfusion recovery.

The proteome of red cell membranes and vesicles during storage in blood bank conditions.

BACKGROUND: During storage of red cells (RBCs) for transfusion, RBCs undergo a number of biochemical and morphologic changes. To be able to identify the mechanisms underlying these storage lesions, a proteomic analysis of the membranes of RBCs and their vesicles was performed during various periods of storage in blood bank conditions. STUDY DESIGN AND METHODS: RBCs and vesicles were isolated from RBCs after various storage periods. The proteins of RBC membranes and vesicles were separated by gel electrophoresis and identified by a semiquantitative proteomic analysis. RESULTS: Our findings confirm previous data, such as a storage-associated increase in hemoglobin binding to the membrane and aggregation and degradation of the integral membrane protein band 3, suggesting a remodeling of the RBC membrane during storage. Our data also show storage-dependent changes in the membrane association of proteasome and chaperone proteins, metabolic enzymes, small G proteins, and signal transduction proteins. Vesicles display similar changes in their protein composition during storage. CONCLUSION: The results of this analysis indicate that the storage-related changes in the RBC membrane are the results of disturbance and/or acceleration of physiologic processes such as cellular aging, including vesicle formation. The latter may serve to remove damaged membrane patches that would otherwise lead to accelerated RBC removal. These data provide a framework for future studies toward the development of better storage conditions and a reduction of the side effects of RBC transfusion.