bluuebunny/crossref_metadata_2025_split huggingface dataset:
HLA class I‐eluted platelets as an alternative to HLA‐matched platelets
Authors: Novotny V. M. , Huizinga T. W. , Van Doorn R. , Briet E. , Brand A. 
Published: March 2003

BACKGROUND: Alloimmunized refractory thrombocytopenic patients often require HLA‐matched platelet transfusions. As the HLA system is very polymorphic, sufficient HLA‐matched donors are not available for every patient.STUDY DESIGN AND METHODS: In vitro elution techniques with citric acid incubation of platelets at pH 3.0 showed that platelets lose expression of HLA, whereas platelet‐specific glycoproteins are preserved. This technique was modified for clinical use. Random‐donor platelet concentrates were incubated with citric acid, subsequently washed, and transfused to two patients.RESULTS: Platelet‐specific glycoproteins were unaffected, and HLA expression decreased generally to below 25 percent of the initial expression. One alloimmunized patient who was without compatible donors because of a rare HLA type underwent repeated transfusions with acid‐treated platelets. In contrast to the results with random‐donor platelet transfusions, posttransfusion increments up to 47 × 10(9) per L were obtained with acid‐treated platelets, and profuse gastrointestinal bleeding was stopped, while multiple skin hemorrhages were resolved. No side effects were observed. A second patient developed a severe transfusion reaction without platelet increment after one transfusion with acid‐treated platelets expressing 30 percent of the original HLA antigens. Further transfusions were not given.CONCLUSION:Standardization of the acid elution technique and validation of the technique in patients is necessary. The results suggest, however, that HLA‐eluted platelets prepared under specified conditions may gain a place in platelet transfusion therapy.
Safety and efficacy of hepatitis C virus antibody screening of blood donors with two sequential screening assays
Authors: Allaina J.P. , Kitchens A. , Aloysiuis S. , Reeves I. , Petrik J. , Barbara J. A. J. , Williamson L.M. 
Published: March 2003

BACKGROUND: Reactive samples in hepatitis C virus (HCV) antibody screening of blood donors are currently referred for a confirmatory assay. This scheme is not optimally efficient and is expensive because of the lack of specificity and cost of confirmatory tests, as well as the need to discard false‐positive donations. As in some human immunodeficiency virus antibody‐confirmatory schemes, the safety and efficacy of confirming anti‐HCV with two sequential screening assays were evaluated.STUDY DESIGN AND METHODS: Three combinations of two anti‐HCV screening assays were used to test 75,874 blood donors. Results were compared with the routine testing scheme and HCV RNA detection in any enzyme immunoassay‐repeatably reactive samples.RESULTS: The use of an alternative screening assay for repeat testing decreased the proportion of enzyme immunoassay‐positive donors from 0.28 to 0.05 percent. All samples that were “confirmed” as positive by the standard combination of immunoassays and all HCV RNA‐positive samples were detected by the sequential screening assays. No samples that had discordant results on primary and secondary screening assays were confirmed by recombinant immunoblot assay or were found to contain detectable HCV RNA.CONCLUSION: The combination of screening assays for anti‐HCV confirmation was as safe as, cheaper than, and nearly as efficient as the standard testing scheme.
Clinical trial and local process evaluation of an apheresis system for preparation of white cell‐reduced platelet components
Authors: Adams M. R. , Dumont L. J. , McCall M. , Heaton W. A. 
Published: March 2003

BACKGROUND: A new method for the consistent preparation of white cell (WBC)‐reduced plateletpheresis components, the Spectra Leukoreduction System (LRS), was evaluated by clinical trial and local process validation. The centrifuge‐based system was projected to decrease the WBC content of plateletpheresis components to a level below 1 × 10(6) per unit. Phase I and II clinical trials were performed. The manufacturer's claims were then tested at the local level with an ongoing quality assurance program.STUDY DESIGN AND METHODS: In Phase I, a cross‐over analysis of five subjects compared LRS to standard plateletpheresis procedures in collection efficiency and component quality: a panel of in vitro measures was taken on Day 0 and Day 5. In Phase II, the LRS process was tested on a larger scale (n = 57; control = 58) with component transfusion. Finally, validation, determination of degree of conformance with standards, and ongoing quality control were performed locally on a newly installed instrument.RESULTS: Phase I and II trials revealed no significant differences between LRS and control units in donor or recipient safety and comfort, platelet function and yield, or component volume. WBC per‐unit values were significantly different: the LRS median per unit was 3.2 × 10(4) WBCs, versus 81.4 × 10(4) for control units. Assessment of process capability gave an estimate of 99‐percent confidence that 99.5 percent of LRS units would be WBC reduced to < 1 × 10(6) WBCs. Local process validation and quality control revealed 90‐percent confidence that 99 percent of the units would be WBC reduced and 99.9‐percent confidence that 75 percent would exceed platelet yield standards; the process was stable over time.CONCLUSIONS: The LRS is safe for apheresis and the component produced is safe for transfusion with platelet function and yield equivalent to controls and WBC reduction superior to controls. Local process evaluation confirmed that component quality meets the goals of the institution.
Effect of 24‐hour storage at 25°C on the in vitro storage characteristics of CPDA‐ 1 packed red cells
Authors: Ruddell J.P. , Lippert L.E. , Babcock J.G. , Hess J.R. 
Published: March 2003

BACKGROUND: Packed red cells (RBCs) warmed above 10 degrees C are generally discarded. Few data exist on the degree of accelerated metabolism and increased hemolysis of packed RBCs allowed to warm.STUDY DESIGN AND METHODS: Twenty‐four CPDA‐1 packed RBC units were combined in 3‐unit pools and subdivided into 2 test units and a control unit. One test unit from each pool was warmed to 25 degrees C for 24 hours on Day 6 and the other test unit was warmed on Day 20; control units were maintained at 1 to 6 degrees C. RBC and supernatant chemistries and RBC morphology were measured weekly (Days 0, 7, 14, 21, and 28) and on the day before warming (Days 6 and 20).RESULTS: Warming CPDA‐1 packed RBCs accelerated the catabolism of glucose 10‐fold and produced concentrations of glucose, lactate, and ATP after 25 days of storage that were equivalent to those in unwarmed units at 35 days. Supernatant sodium and potassium concentrations were corrected partially with warming. RBC morphology transiently normalized with warming and without increased hemolysis; no bacteria growth was detected.CONCLUSION: One day of 25 degrees C storage of CPDA‐1 packed RBCs accelerates essential metabolite break‐down equivalent to 10 days of storage at 1 to 6 degrees C. It does not appear to matter whether the packed RBCs are warmed on Day 6 or Day 20. This information may be useful in determining the acceptability of blood allowed to warm above 10 ° C.
Expression of neutrophil antigens after 10 days of granulocyte‐colony‐stimulating factor
Authors: Stroncek D.F. , Jaszcz W. , Herr G.P. , Clay M.E. , McCullough J. 
Published: March 2003

BACKGROUND:Granulocyte‐colony‐stimulating factor (G‐CSF) is becoming the standard agent for mobilizing granulocytes. Most granulocyte donors are given a single dose of G‐CSF, but in some cases they are given G‐ CSF for several days, and multiple granulocyte concentrates are collected. The administration of a single dose of G‐CSF induces several changes in the expression of neutrophil antigens, but the effects of multiple daily doses of G‐CSF are not known.STUDY DESIGN AND METHODS:Seven healthy people received 5 microg per kg of G‐CSF for 10 days. Their expression of several neutrophil antigens before, during, and after the administration of G‐CSF was analyzed through the use of flow cytometry.RESULTS:The expression of L‐selectin (CD62L), Fcgamma receptor (FcgammaR) III (FcgammaRIII, CD16), and the leukocyte function antigen (CD11a) decreased throughout the course of G‐CSF administration, while the expression of FgammaR I (FcgammaRI, CD64) and lipopolysaccharide‐binding protein receptor (CD14) increased. The expression of FcgammaR II (FcgammaRII, CD32) also increased, but not until the fourth day of G‐CSF administration. The expression of amino peptidase N (CD13), C3bi receptor (CD11b), and the neutrophil beta2 integrin unit (CD18) did not change during the administration of G‐CSF, but that of both CD13 and CD18 increased 3 days after the last dose. The expression of neutrophil‐specific antigen NB1 initially increased, returned to pre‐G‐CSF levels after 4 days, and then increased again after 10 days of G‐CSF administration. CONCLUSION: Changes in the expression of several neutrophil antigens occurred throughout a 10‐day course of G‐CSF Most of the changes occurred after one dose, but additional changes occurred later in the 10‐day course and after its completion. These changes may affect the function of G‐CSF‐mobilized granulocytes.
Surveillance for Creutzfeldt‐Jakob disease among persons with hemophilia
Authors: Evatt B. , Austin H. , Barnhart E. , Schonberger L. , Sharer L. , Jones R. , DeArmond S. 
Published: March 2003

BACKGROUND: Although Creutzfeldt‐Jakob disease (CJD) has been shown to be transmissible through blood components in rodent models, no human blood‐to‐blood transmission has been documented. If blood transmission were possible in humans, persons with hemophilia in the United States would be at higher risk of contracting CJD, because they receive large numbers of blood components. Nearly one‐half of the hemophilia population contracted HIV in the 1980s, and many of these people have since died with neurologic complications. This study investigated whether some hemophilia patients with neurologic disorders may have died with CJD.STUDY DESIGN AND METHODS: Hemophilia treatment Centers across the United States were invited to participate in this retrospective surveillance study. The centers were asked to send any available formalin‐fixed paraffin block brain samples from hemophilia decedents. Slides were prepared at the Centers for Disease Control and Prevention and reviewed by three expert neuropathologists. Two slides were stained for the prion protein at the request of one of the neuropathologists.RESULTS: Specimens from 24 decedents with genetic bleeding disorders were collected and reviewed. The panel found no evidence of CJD in any of the specimens.CONCLUSIONS: Although the study sample is small, these results support the growing evidence that CJD is not being transmitted in the nation's blood supply.
Cost‐effectiveness of transfusing virus‐inactivatedplasma instead of standard plasma
Authors: Pereira A. 
Published: March 2003

BACKGROUND: Virus inactivation of plasma intended for transfusion avoids the transmission of hepatitis B virus, hepatitis C virus, and HIV. However, because most plasma recipients also receive other blood components concomitantly, the procedure reduces but cannot eliminate the risk of transfusion‐transmitted infection. As virus‐inactivated plasma has just been licensed in the United States and other countries, a cost‐effectiveness analysis is pertinent.STUDY DESIGN AND METHODS: A Monte Carlo simulation of a Markov model representing the possible outcomes of plasma recipients was used to derive costs and utilities of transfusing virus‐inactivated plasma instead of standard plasma. Probability distributions for patients' age and sex and for the number of blood components transfused per case were determined in 924 plasma recipients in a tertiary‐care hospital. Other values were obtained from the medical literature. Results of the baseline and sensitivity analyses are the mean (± SD) of 10 simulations with 107 patients per simulation.RESULTS: In the baseline analysis, transfusing virus‐inactivated plasma instead of standard plasma prolonged the quality‐adjusted survival by 1 hour and 11 minutes per patient, at a cost‐effectiveness ratio of $2,156,398 ± $257,587 per quality‐adjusted life year gained. Cost‐effectiveness was most sensitive to the patients' mean age, the incremental cost per unit of virus‐inactivated plasma, the HIV and hepatitis C virus transmission rates, and the short‐term mortality of plasma recipients due to their underlying diseases.CONCLUSIONS: Compared to most accepted medical procedures, the transfusion of virus‐inactivated plasma produces little health benefit at a very high cost. This poor cost‐effectiveness ratio is due to the low current risk of infection with transfusion‐transmitted viruses and to the greater age and poor short‐term prognosis of most plasma recipients.
Evaluation by enzyme‐linked immunosorbent assay of IgG anti‐D and IgG subclass concentrations in immunoglobulin preparations
Authors: Ahaded A. , Debbia M. , Beolet M. , Le Pennec P.Y. , Lambin P. 
Published: March 2003

BACKGROUND: Anti‐D immunoglobulin preparations are injected to prevent hemolytic disease of the newborn. The concentration of IgG anti‐D in these preparations is usually determined by an automated hemagglutination technique using as a reference a calibrated preparation of anti‐D, but the method requires special equipment and cannot be routinely applied to measure the IgG subclasses of anti‐D in these preparations.STUDY DESIGN AND METHODS: Taking advantage of a recently described enzyme‐linked immunosorbent assay (ELISA) for the determination of the anti‐D concentration in sera of alloimmunized pregnant women, IgG anti‐D and IgG subclass concentrations were measured in the international reference preparation (IRP) coded 68/419, 10 anti‐D immunoglobulin preparations, and sera of 15 D‐immunized volunteers.RESULTS: An IgG anti‐D concentration of 61.5 ± 4.8 μg per ampoule (mean ± SD) was found by ELISA in IRP 68/419. This result was in agreement with previous determinations obtained by radioimmunoassay (60 μg/ampoule). The IgG subclass concentration of anti‐D in this preparation was 48.4 μg of IgG1 (78.6%), 3.0 μg of IgG2 (4.8%), 9.7 μg of IgG3 (15.8%), and 0.4 μg of IgG4 (0.7%) . The mean proportion of IgG subclasses of anti‐D in 10 immunoglobulin preparations was similar (81.7% for IgG1, 5.0% for IgG2, 12.7% for IgG3, and 0.6% for IgG4). In the sera of 15 immunized volunteers, the IgG anti‐D concentration varied from 3.1 to 68.4 μg per mL. The mean IgG subclass composition of anti‐D was 79.3 percent for IgG1, 2.2 percent for IgG2, 18.1 percent for IgG3, and 0.4 percent for IgG4. The proportions of IgG3 anti‐D in these sera were found to range between 1 percent and 87 percent, as in the sera of D‐alloimmunized pregnant women.CONCLUSION: ELISA provides an alternative to the radioimmunoassay and the automated hemagglutination technique. In addition, it allows the evaluation of the absolute concentration of each IgG subclass of anti‐D in immunoglobulin preparations and necessitates only the conventional equipment required for an immunoenzymatic assay.
Biocompatibility of a new cell separator studied by flow cytometry: analyses of platelet antigens during apheresis and storage
Authors: Gutensohn K. , Alisch A. , Crespeigne N. , Eifrig B. , Kuehnl P. 
Published: March 2003

BACKGROUND: Alterations of platelet antigens are known to occur during cytapheresis and storage. These changes have been shown to be dependent on the biomaterials, techniques, and devices used. In this study, the influence of a new cell separator (AMICUS) and storage container (PL‐2410) on platelet glycoproteins was analyzed.STUDY DESIGN AND METHODS: During plateletpheresis and storage, the levels of platelet glycoproteins and binding of fibrinogen were determined by flow cytometry.RESULTS: During apheresis, mean channel fluorescence intensity of CD41a did not change significantly (p = 0.06). A small increase was evident in CD42b mean channel fluorescence intensity, which rose from a baseline level of 178.6 ± 68.3 to 231.5 ± 97.9 at the end of the procedure (p<0.05); in CD62p‐positive platelets, which increased from 2.0 ± 0.9 percent to 9.9 ± 3.9 percent (p<0.05); in CD63‐positive platelets, which increased from 1.7 ± 0.7 percent to 7.9 ± 2.6 percent (p<0.05); and in the binding of fibrinogen, which increased from 1.9 ± 0.8 percent positive platelets to 10.5 ± 2.6 percent (p<0.05). During storage, the mean channel fluorescence intensity of CD41a and CD42b, the percentage of CD62p‐ and CD63‐positive platelets, and the binding of fibrinogen to platelets showed no significant change.CONCLUSION: These studies show that alterations in platelet antigens and platelet activation occur to a small degree during apheresis and storage. These findings demonstrate generally good biocompatibility of this new cell separator.
Platelet concentrates prepared and stored under currently optimal conditions: minor impact on platelet adhesive and cohesive functions after storage
Authors: Lozano M. , Estebanell E. , Cid J. , Diaz‐Ricart M. , Mazzara R. , Ordinas A. , Escolar G. 
Published: March 2003

BACKGROUND: The effect on platelets of two standard methods of platelet concentrate (PC) preparation was studied by flow cytometry. The findings were correlated with those obtained in an experimental in vitro perfusion model.STUDY DESIGN AND METHODS: PCs were prepared from whole blood by the platelet‐rich plasma (PRP) or buffy coat (BC) method and placed on a flatbed platelet agitator at 22°C for up to 5 days. Platelet glycoproteins (GP)Ibα, GPIIb/IIIa, and GPIV, p‐selectin and lysosomal integral membrane protein, and the binding of von Willebrand factor, fibrinogen, fibronectin, and coagulation factor Va were measured with the corresponding specific conjugated antibodies. Perfusions were carried out in an annular chamber with citrated blood depleted of platelets and white cells by filtration, to which samples from PCs were added.RESULTS: PRP‐PC production provoked intense platelet activation. In contrast, in BC‐derived PCs, platelet activation was milder, and only a significant increase in bound fibrinogen was seen. After 1 day of storage, differences between the methods that had been observed immediately after separation had almost disappeared. During the remaining storage period, increases in activation‐dependent antigens and in procoagulant activity were measured. Of the studied platelet GPs, only GPIIb/IIIa decreased by 25 percent in PRP‐PCs. Differences in covered surface were not significant in perfusion studies performed on Day 0 and after 5 days of storage in PRP‐PCs (26.8 ± 6.9 vs. 20.5 ± 5.8) or BC‐PCs (23.8 ± 11 vs. 24.8 ± 10.2).CONCLUSION: Platelet activation occurred during the separation and storage of PCs prepared by both methods, and it was higher in PRP‐PCs only in samples obtained immediately after preparation. Despite these changes, platelet adhesive and cohesive functions were similar in both types of PCs and remained basically unchanged after storage.
Granulocyte storage and antigen stability
Authors: Chun H. , Cipolone K. , Procter J. , Stroncek D.F. 
Published: March 2003

BACKGROUND: Current methods for the detection of granulocyte antibodies require panels of freshly isolated cells. This makes these assays time‐consuming, costly, and technically difficult.STUDY DESIGN AND METHODS: The immunofluorescence method of detecting the binding of antibodies to granulocytes was modified for use with a flow cytometer, and methods were tested to store granulocytes for use in that assay. Granulocytes were stored at 4°C for 7 days under three conditions: 1‐percent formaldehyde‐fixed cells were stored in Hanks' balanced salt solution (HBSS); untreated cells were stored in tissue culture medium (RPMI‐1640); and cells were fixed and stored with a commercial white cell‐storage solution (Cyto‐Chex Reagent). Antigen stability was evaluated by using monoclonal antibodies (MoAbs) and alloantibodies. Serologic studies were done by an indirect immunofluorescence assay and assessed by flow cytometric analysis.RESULTS: On Day 2, only 2 to 7 percent of granulocytes stored in RPMI‐1640 remained. On Day 7, 67 to 76 percent of granulocytes fixed in formaldehyde and stored in HBSS remained, and 47 to 87 percent of granulocytes stored in a white cell‐storage solution remained. All antigens were detectable by the MoAbs and alloantisera on Day 7. However, nonspecific staining by the fluorescein isothiocyanate (FITC)‐conjugated secondary antibody hindered interpretation of test results on Day 4. Nonspecific staining occurred over time and was associated with increased cell permeability during storage. Two sources of nonspecific staining were identified. The first source was the FITC‐conjugated secondary antibody; it was eliminated by switching to a phycoerythrin conjugate. The second source was factors in human serum; it was resolved by examining only viable, impermeable cells identified by using 7‐aminoactinomycin‐D.CONCLUSION: Granulocytes and their antigens can be preserved for at least 7 days, but evaluation of antibody reactions was possible for only 4 days as a result of nonspecific staining due to enhanced membrane permeability of dying cells.
Serology of antibodies to second‐ and third‐generation cephalosporins associated with immune hemolytic anemia and/or positive direct antiglobulin tests
Authors: Arndt P.A. , Leger R.M. , Garratty G. 
Published: March 2003

BACKGROUND: First‐generation cephalosporins rarely caused immune hemolytic anemia (IHA). Second‐ and third‐generation cephalosporins, especially cefotetan and ceftriaxone, are increasingly associated with severe, sometimes fatal IHA.STUDY DESIGN AND METHODS: Samples from 53 patients with drug‐induced IHA and/or positive direct antiglobulin test (DAT) were tested. Patients' sera were tested against drug‐treated red cells (RBCs) and untreated or enzyme‐treated RBCs, with and without the addition of drug solution. Eluates from patients' RBCs were tested against drug‐treated and untreated RBCs.RESULTS: Forty‐three patients had antibodies to cefotetan, 8 to ceftriaxone, 1 to cefoxitin, and 1 to cefotaxime. All patients had a positive DAT; only anti‐cefoxitin and anti‐cefotetan were demonstrable in RBC eluates. Sera containing anti‐cefoxitin, anti‐cefotaxime, and anti‐cefotetan reacted with drug‐treated RBCs (100%) and untreated or enzyme‐treated RBCs in the presence of drug (98% or 100%, respectively). All of the ceftriaxone antibodies reacted with untreated or enzyme‐treated RBCs in the presence of drug, but those tested did not react with ceftriaxone‐treated RBCs. In addition to cefotetan‐dependent antibodies, 19 (44%) and 14 (33%) of 43 sera contained drug‐independent antibodies when tested with and without the presence of a polyethylene glycol potentiator, respectively.CONCLUSION: Cefotetan is by far the most common cause of drug‐induced IHA. All cefotetan antibodies and the single examples of cefoxitin and cefotaxime antibodies reacted with drug‐coated RBCs, and most, in contrast to the reactions of antibodies to first‐generation cephalosporins (e.g., cephalothin), also reacted with RBCs (not treated with drug) in the presence of the drug. Ceftriaxone antibodies reacted only by the latter mechanism. Drug‐independent antibodies (i.e., those reacting without any drug being present) were detected in 33 to 44 percent of patients' sera containing cefotetan antibodies, depending on the sensitivity of the method used.