Search

Background: Pathogen inactivation treatments such as INTERCEPT aim to make sure blood and blood-derived products are free of pathogens before using them for transfusion purposes. At present, there is no established quality control assay that assesses the completeness of the treatment. As INTERCEPT is a photochemical treatment known to generate reactive oxygen species we sought to use the antioxidant power (AOP) of the blood product as a marker of treatment execution. In this perspective, we evaluated an electrochemically based miniaturized system, the EDEL technology, for measuring the AOP in both platelet concentrates (PCs) and plasma., Study Design and Methods: Aliquots were withdrawn from PCs or plasma units before and after INTERCEPT treatment and a few microliters were directly deposited into the EDEL sensor for the AOP measurement. The result is expressed in EDEL, an arbitrary unit (micromolar equivalent of ascorbic acid)., Results: The INTERCEPT treatment resulted in a significant decrease of the AOP. An AOP threshold of 66.5, 89.0, 59.8, and 131.5 EDEL was determined for apheresis PCs collected from female and male donors, buffy coat PCs, and plasma units, respectively. Below the threshold value, INTERCEPT treatment is considered to be executed. Additionally, we showed that the presence of the photosensitizer in combination with the ultraviolet A illumination is required to observe the AOP decrease., Conclusion: The measurement of the AOP of PCs and plasma units can be used to document the completeness of the INTERCEPT treatment., (© 2016 AABB.)

Background: Collection of hematopoietic progenitor cells by apheresis (HPC-A) requires separation of cells by density. Previous studies highlighted the challenges of HPC-A collection from patients with abnormal red blood cells (RBCs). TEMPI syndrome is a recently described condition defined by teleangiectasias, elevated erythropoietin and erythrocytosis, monoclonal gammopathy, perinephric fluid collections, and intrapulmonary shunting. Patients with TEMPI syndrome have responded to therapies used to treat plasma cell dyscrasias and may benefit from autologous HPC transplantation. We report HPC-A collection from a patient with TEMPI syndrome that was complicated by severe iron deficiency., Study Design and Methods: The patient received granulocyte-colony-stimulating factor (G-CSF) and plerixafor for HPC mobilization and underwent 3 days of HPC-A collection., Results: The patient presented for collection with a microcytic erythrocytosis. Over 3 days, approximately 50 L of whole blood was processed, and 2 × 10(8) CD34+ cells were collected (2.8 × 10(6) CD34+ cells/kg). The mean collection efficiency (CE), percentage of mononuclear cells, hematocrit (Hct), and RBC count were 18%, 90%, 14%, and 9 × 10(11) , respectively. Altering collection variables to avoid RBC contamination reduced CE. Ficoll preparations of the products after freeze-thaw showed RBC contamination and hemolysis. Postthaw viability exceeded 95%. The products were not RBC reduced or washed. There were no adverse reactions during or after infusion., Conclusions: HPC-A collection from a patient with TEMPI syndrome was complicated by microcytic erythrocytosis, leading to RBC contamination and hemolysis in the product. Adequate HPCs were collected and the patient tolerated infusion without RBC depletion or washing. Our report highlights difficulties of HPC-A collection from iron-deficient patients., (© 2015 AABB.)

Background: Sickle cell disease (SCD) has become a major public health issue. Hydroxyurea and red blood cell (RBC) transfusion are the cornerstone treatments. Erythrocytapheresis (ECP) is an automated method for transfusion exchange. Given that ECP requires more blood than conventional transfusion, there is concern about alloimmunization and hemolytic transfusion reactions. We evaluate the incidence of hemolytic transfusion reactions and alloimmunization rates in patients receiving conventional blood transfusions and in patients participating in long-term blood exchange programs with ECP., Study Design and Methods: All hemolytic transfusion reactions and alloimmunizations in SCD patients were recorded over the period 2006 to 2011. Conventional transfusions and ECP were compared., Results: The cohort consisted of 188 SCD patients. The median (±SD) age was 23 (±14) years. The ECP and conventional transfusion groups comprised 49 and 139 patients, respectively. The prevalence of alloimmunization was 33% in the ECP group and 22% in the conventional transfusion group (p = 0.1797). The alloimmunization/RBC unit (RBCU) ratio was lower in the ECP group than in the conventional transfusion group (1.6 and 11.6 per 1000, respectively; p < 0.0001). Although patients in the ECP group received more than 10 times more RBCUs than patients in the conventional transfusion group (206 vs. 19 RBCUs per patient, respectively; p < 0.0001), none of the four recorded hemolytic transfusion reactions (n = 4) occurred., Conclusion: Regarding alloimmunization, ECP exhibits a good immunohematologic safety profile relative to conventional transfusion in a large SCD mainly adult cohort., (© 2014 AABB.)

Background: Several preventive measures, including diversion of the first aliquot of blood and culturing of platelet (PLT) components, have been implemented to decrease the risk of transfusion-transmitted bacterial infections (TTBIs). We evaluated the effectiveness of these measures in Québec using hemovigilance data from January 2000 to December 2008., Study Design and Methods: Adverse transfusion reactions were reported to the Québec Ministry of Health by transfusion safety officers. Initial aliquot diversion, already in place for apheresis PLTs, was added to all whole blood collections in early 2003. Bacterial detection was implemented in March 2003 for apheresis PLTs and February 2005 for whole blood-derived PLTs (WBDPs)., Results: The incidence of probable and definite TTBIs associated with WBDPs decreased from 1 in 2655 to 1 in 27,737 five-unit pools (p = 0.004) after implementation of diversion. There were no reports of TTBIs with WBDPs after culture was added to diversion, further reducing the risk to 1 in 58,123 five-unit pools (p < 0.001). There was only one TTBI associated with apheresis PLTs during the 9-year period, which occurred after implementation of both diversion and culture., Conclusion: Hemovigilance data demonstrated a highly significant decrease in TTBIs associated with WBDPs, mainly attributed to the implementation of diversion. However, diversion and culture do not totally abolish the risk of TTBIs., (© 2010 American Association of Blood Banks.)

Background: Blood platelets (PLTs) link the processes of hemostasis and inflammation. Recent studies have demonstrated that PLTs promote immunity and inflammation mainly by means of the CD40/CD40L pathway. Our objective was to describe the accumulation of cytokines in PLT concentrates during storage., Study Design and Methods: Pools of PLT concentrates were prepared, separated from plasma, and resuspended in clinical-grade storage medium; samples were taken on Days 0, 1, 2, 3, and 5 for analysis, without replacement (i.e., without soluble protein dilution). Interleukin (IL)-6, IL-8, PLT-derived growth factor (PDGF)-AA, soluble CD40 ligand (sCD40L), RANTES, and transforming growth factor-beta production were measured by specific enzyme-linked immunosorbent assays., Results: Over time, the levels of RANTES, IL-8, and IL-6 were stable. In contrast, the levels of PDGF-AA and sCD40L increased. Ex vivo production of sCD40L was quantified at levels sufficient to induce B-cell effects based on previous studies of in vitro induced B-cell activation and differentiation by sCD40L. Cytokine and/or chemokine levels were generally higher in PLT concentrate supernatants and/or PLT lysates in comparison to PLT-free plasma, allowing the determination of which cytokine and/or chemokine was absorbed or secreted by transfusion-grade PLTs over time., Conclusion: Our data provide evidence that stored PLTs contain molecules with known immunomodulatory competence and secrete them differentially over time during storage for transfusion purposes.

Background: Erythrocytapheresis is used to prevent acute chest syndrome and stroke in patients with sickle cell disease (SCD). However, such regimens are associated with significant risks, such as iron overload and potential exposure to transfusion-transmitted infectious diseases. Computer modeling of erythrocytapheresis procedures may help optimize treatments and minimize risks., Study Design and Methods: Mathematical models based upon material balance equations and patient-specific statistical analyses were developed to estimate HbS levels immediately after erythrocytapheresis and immediately before the next treatment. The equations were incorporated into a software application that was used to model the effects of various treatment values on four patients treated with 90 erythrocytapheresis procedures., Results: Immediate postprocedure HbS values were accurately estimated with correlations between measured and calculated values ranging from R(2) = 0.83 to 0.96. Estimates of HbS just before the next treatment correlated well in three patients (R(2) = 0.71 to 0.83) but poorly in one (R(2) = 0.28 to 0.46). Varying the treatment values by computer simulation led to a wide variation in the number of RBC units and the net RBC volume transfused., Conclusion: Computer modeling of erythrocytapheresis can be used to optimize chronic treatment regimens for SCD patients and potentially to minimize the risks of overtransfusion.

Background: MNCs for adoptive immunotherapy may be collected by leukocytapheresis with a cell separator., Study Design and Methods: Six healthy cytapheresis donors donated two MNC concentrates on a cell separator (AS.TEC 204, Fresenius): one on the standard MNC program and one on a modified MNC program with reduced centrifuge velocity that leads to a lower platelet contamination. Seventeen patients with malignant melanoma donated 26 MNC concentrates: 5 on the AS.TEC 204 MNC program, 9 on the modified AS.TEC 204 MNC program, and 12 on another modified MNC program (Spectra, COBE)., Results: In the course of cultivation of MNCs to dendritic cells (DCs), the donor MNC concentrates with the lower platelet contamination (475 +/- 85 x 10(9)/L) had a significantly higher relative DC yield (low platelet contamination: 3.9 +/- 1.6% of the plated cells; high platelet contamination: 2.5 +/- 1.8% of the plated cells; p = 0.019) than the concentrates with the higher platelet contamination (2364 +/- 448 x 10(9)/L). No significant difference was found in the yields of MNCs and CD14+ cells in the three protocols used for the collection of MNCs from patients with melanoma. The components obtained by the standard AS.TEC 204 MNC program had a significantly higher platelet contamination (1768 +/- 994 x 10(9)/L) than the components obtained by the modified AS.TEC MNC program (360 +/- 98 x 10(9)/L; p<0.05) and the modified Spectra MNC program (636 +/- 266 x 10(9)/L); p<0.05). Because of the low number of investigated components, no significant difference in the DC yield of the three protocols could be detected (mean DC yield after cultivation: 746 +/- 429 x 10(6))., Conclusion: A high platelet contamination of MNC concentrates intended for adoptive immunotherapy can lead to a significant impairment of the DC yield after cultivation. Both the modified AS.TEC 204 and the modified Spectra MNC programs are well suited for collecting MNC concentrates with high MNC yields and low platelet contamination from patients with malignant melanoma.

Background: Determination of the optimal duration of apheresis requires a careful examination of blood progenitor cell (BPC) kinetics during apheresis. Intra-apheresis recruitment of BPCs should be evaluated., Study Design and Methods: Twenty-six apheresis procedures were performed in 13 children with various malignant disorders (ages, 10 months to 17 years; median, 7 years) to collect BPCs for autologous transplant, using a blood cell separator with 2 to 5.2 blood volumes processed. The subjects were divided into three groups according to age: below 1 year (n = 4), 2 to 10 years (n = 5), and 11 to 20 years (n = 4). BPCs were mobilized by a combination of chemotherapy and granulocyte-colony-stimulating factor (G-CSF; 2-7.5 micrograms/kg/day intravenous drip). The levels of circulating CD34+ cells and colony-forming units-granulocyte-macrophage (CFU-GM) were monitored to examine intra-apheresis recruitment. For every 50 mL per kg or 2 L of processed blood, 5-mL blood samples were collected via a central line., Results: In the first apheresis procedure, more CD34+ cells were mobilized by the procedure itself in the infant group than in the older groups, and the number of cells decreased with the subject's age. When the same analysis was made during the second apheresis procedure, performed 1 day later, the levels of both CD34+ cells and CFU-GM had decreased to below the preapheresis values in all of the populations. Cell yields in the second apheresis procedure were significantly lower than those in the first., Conclusion: Although several factors prevent a reliable analysis, the data suggest that the intra-apheresis recruitment of BPCs may be age-specific; the continuous and prolonged supply of cells from the bone marrow to peripheral blood that occurs during apheresis is more predominant in infants, which leads to the collection of proportionately more BPCs in younger children than in their older counterparts.

Background: The collection of allogeneic lymphocytapheresis and granulocytapheresis components containing significant volumes of ABO-incompatible red cells is sometimes necessary., Study Design and Methods: Twenty-nine ABO-incompatible lymphocytapheresis components collected for transfusion to three patients and 11 ABO-incompatible granulocytapheresis components collected for transfusion to five patients were depleted of red cells by gravity sedimentation aided by the addition of hetastarch solution. The efficacy of red cell depletion and white cell retention and the complications of transfusion were analyzed., Results: Lymphocytapheresis components contained 82 +/- 13 percent of the original white cells and 5 +/- 3 mL of red cells after depletion; however, for those components containing < 70 mL of red cells before depletion (n = 12), white cell recovery was 92 +/- 5 percent. After depletion, granulocytapheresis components contained 96 +/- 3 percent of the original white cells and 6 +/- 2 mL of red cells. No clinical or laboratory evidence of hemolysis was observed after the transfusion of any leukapheresis component., Conclusion: Red cells can be effectively removed from leukacytapheresis components by a simple gravity sedimentation technique with added hetastarch. This allows safe transfusion of ABO-incompatible components.

Background: The preparation of blood components by hard centrifugation results in red cell concentrates with a small amount of plasma. The influence of various plasma factors, temperature, and storage time on white cell reduction by filtration was studied., Study Design and Methods: Red cell concentrates were suspended in 100 mL of saline-adenine-glucose-mannitol (SAGMAN) solution or in SAGMAN solution in which 5 or 10 mL had been replaced with an equal amount of fresh plasma, albumin (4%), or heat-inactivated plasma. After overnight storage at 4 degrees C, filtration at a slow flow rate (2 hours) was performed. The effect of temperature was studied by filtration at 4 degrees C and 37 degrees C. To study the influence of storage time, red cell concentrates were stored for 4 to 8 hours or 14 to 20 hours at 4 degrees C and filtered through another model of filter. The number of white cells was counted microscopically or by flow cytometry., Results: When 5 or 10 mL of plasma was added, a significantly smaller number of white cells were found after filtration than were found in the SAGMAN control (the median difference between pairs: 23.6 x 10(6) for 5 mL [p = 0.006] and 14.9 x 10(6) for 10 mL [p = 0.003]). The number of white cells was significantly higher with 10 mL of albumin than with 10 mL of plasma (difference, 15.0 x 10(6); p = 0.006). When heat-inactivated plasma was used, the number of white cells was significantly lower than when fresh plasma was used (difference, 0.3 x 10(6); p = 0.009). Filtration at 37 degrees C resulted in a 64-percent reduction in white cells and that at 4 degrees C led to a 99.7-percent reduction (p = 0.006). When the second filter was used, a slight but significantly lower number of white cells was found in the red cell concentrate stored for 14 to 20 hours than in that stored for 4 to 8 hours (difference, 0.03 x 10(6); p < 0.001)., Conclusion: The amount of plasma in the red cell concentrate and the storage time and temperature are important factors in the outcome of white cell reduction by filtration. The effect of plasma does not seem to be due to a general influence of protein or to the activity of complement or fibrinogen.

Background: Historically, paid blood donors were found to transmit hepatitis at higher rates than volunteers. In those older studies, paid donors frequently were recruited from prisons or slum areas--a finding consistent with the belief that monetary payment in itself did not necessarily lead to the high-risk status of commercial blood. Instead, it was the population base from which the donors were recruited that was important., Study Design and Methods: Today, cytapheresis donors are in great demand. Because payment is one incentive that might entice donors to undertake the increased commitment of repeated cytapheresis donation, the results were studied of infectious disease history and laboratory testing performed concurrently in 917 volunteer whole-blood donors and 1240 paid cytapheresis donors, who were enrolled in distinct programs at the DeGowin Blood Center from October 7, 1987, through November 30, 1990., Results: When first, repeat, and overall donations made by these donors were evaluated separately, paid cytapheresis donors were found to exhibit no increase in infectious disease history or test results beyond those of volunteer whole-blood donors., Conclusion: Thus, paid cytapheresis donors, when managed within a formal program, should not necessarily be presumed to be more dangerous than volunteers, from an infectious disease aspect. However, definitive proof of safety (comparison of transfusion-transmitted infection rates in two groups of patients receiving blood components exclusively from either paid cytapheresis or volunteer donors) was not pursued by long-term follow-up studies.