bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibodies to private and public HLA class I epitopes in platelet recipients
Authors: Zimmermann R. , Wittmann G. , Zingsem J. , Blasczyk R. , Weisbach V. , Eckstein R. 
Published: March 2003

BACKGROUND: Transfusions or pregnancies can cause immunization against private HLA determinants and public epitopes shared by more than one private HLA antigen. HLA antibodies are correlated with febrile transfusion reactions, lower platelet response following platelet transfusion, and an increased rate of renal transplant rejection. Until now, antibody specificities in alloantisera from platelet recipients have been poorly characterized.STUDY DESIGN AND METHODS: Consecutive serum screens from platelet recipients were analyzed for antibodies against private HLA class I antigens and public HLA epitopes using a serum analysis program based on the 2 × 2 table analysis of correlations. Serum screens of highly immunized patients and of patients with new alloimmunization events were reviewed separately.RESULTS: Of the serum screens from 566 platelet recipients, 1577 indicated alloimmunization (panel‐reactive antibodies >5%). The program assigned a specificity in 1024 of these screens (64.9%) and at least once in 522 of 566 patients (92.2%). In 267 patients, antibodies detecting public epitopes in the combined A‐ or B‐locus cross‐reacting groups were found; other public markers were detected in 39 patients. Patterns of reactivity were remarkably less stable than in patient groups previously studied. In many patients, antibodies with apparent private epitope specificity preceded the identification of antibodies against a shared marker of the same cross‐reactive group. However, the disappearance of antibodies (whether or not this was followed by a new antibody against a private or public marker belonging to another cross‐reacting group) was also observed.CONCLUSION: The computerized analysis of microlymphocytotoxicity tests enhances the rate of antibody specification in sera from platelet recipients with lymphocytotoxic antibodies. The identified antibodies should be taken into account in the selection of platelet donors. The data confirm and extend previous observations on HLA class I antibodies and elucidate new alloimmunization events.
Simultaneous extraction of hepatitis C virus (HCV), hepatitis B virus, and HIV‐1 from plasma and detection of HCV RNA by a reverse transcriptase‐polymerase chain reaction assay designed for screening pooled units of donated blood
Authors: Sun R. , Schilling W. , Jayakar H. , Ku J. , Wang J. , Rosenstraus M. , Spadoro J. 
Published: March 2003

BACKGROUND: Testing for viral nucleic acids should reduce the residual risk of transmitting viral infections by transfusion of blood components. The AmpliScreen Hepatitis C (HCV) Test, Version 2.0, was designed for screening pools composed of samples from individual units of blood or plasma.STUDY DESIGN AND METHODS: An ultracentrifugation step during sample processing simultaneously extracts and concentrates HCV, HIV type 1, and hepatitis B virus particles from plasma. An HCV internal control RNA serves as an extraction and amplification control for each processed sample. Processed samples are amplified by reverse transcriptase polymerase chain reaction and detected by hybridization of the amplified products to HCV‐ and internal‐control‐specific oligonucleotide probes. Plasma samples containing known quantities of HCV were used to evaluate analytical sensitivity and precision.RESULTS: The analytical sensitivity of the test was 25 IU of HCV per mL of pooled plasma; all HCV genotypes were detected with similar efficiency. The test did not react with other blood‐borne viruses. The within‐run and total coefficients of variation were 1.3‐13.0 percent and 1.7‐22.0 percent, respectively, with low copy samples producing the more variable results. The test performed well using plasma collected in either EDTA, ACD, or PPT Vacutainer tubes. Plasma samples containing elevated levels of hemoglobin, albumin, triglycerides, or bilirubin did not interfere with the test. The test detected HCV RNA 23 to 32 days prior to seroconversion for four of the five seroconversion panels tested.CONCLUSION: The AmpliScreen HCV Test, Version 2.0 provides a reproducible and specific method for screening pooled blood units for HCV. Theoretically, this test has sufficient sensitivity to detect a single infected unit containing 2.4 × 103 IU of HCV per mL in a pool with 95 uninfected units and should reduce the window period by at least 20 to 30 days.
Biotinylation modifies red cell antigens
Authors: Cowley Helen W. , Wojda Urszula , Cipolone Karen M. , Procter Jo L. , Stroncek David F. , Miller Jeffery L. 
Published: March 2003

BACKGROUND: Chemical biotinylation of red cell membranes may be useful for several clinical applications, including red cell survival studies.STUDY DESIGN AND METHODS: To examine the possible effects of biotinylation on red cell antigens, standard hemagglutination assays were performed on matched sets of control and biotinylated red cells. The red cells were biotinylated at a final concentration of 2.0 pg of sulfo‐N‐hydroxysuccinimide‐biotin per cell, and antigen‐negative cells were directly compared to antigen‐positive cells when possible. The hemagglutination assays were graded in a blinded fashion. Forty‐one red cell antigens from 21 of the 23 established blood group systems were tested.RESULTS: Hemagglutination based upon antibody binding to A, A1, M, N, S, s, P1, D, C, E, c, e, Cw, Lub, K, k, Kpb, Lea, Leb, Fya, Fyb, Jka, Jkb, Dia, Wra, Wrb, Yta, Xga, Sc1, Dob, Coa, Ch, H, Ge2, Cra, Kna, I, and P was not affected by biotinylation. Unexpectedly, the hemagglutination of Di(b+) and LW(a+) red cells was blocked after biotinylation. Conversely, MH04 monoclonal anti‐A agglutinated red cells expressing B only after biotinylation. BIRMA‐1 monoclonal anti‐A and polyclonal anti‐A from sera did not agglutinate the biotinylated B red cells.CONCLUSION: Biotinylation of human red cells specifically modified their antigenicity, as measured by standard hemagglutination assays.
Preoperative autologous blood donation by 1073 elderly patients undergoing elective surgery: a safe and effective practice
Authors: Gandini Giorgio , Franchini Massimo , Bertuzzo Daniela , Olzer Daniela , Crocco Isabella , De Gironcoli Marzia , Aprili Giuseppe 
Published: March 2003

BACKGROUND: Preoperative autologous blood donation (PABD) aims at avoiding the risks associated with exposure to allogeneic blood. While its use is extremely common among adult patients in connection with elective surgery, it is still uncommon in elderly patients, because of a series of coexisting pathologies.STUDY DESIGN AND METHODS: A retrospective study was made of 1073 consecutive elderly patients at a city hospital from 1990 to 1996. Their responses to the PABD program were evaluated by analysis of the incidence of complications and the demand for allogeneic blood.RESULTS: The PABD program was interrupted in 79 (7.4%) of 1073 patients because of the onset of anemia, vasovagal reactions, lack of accessible superficial veins, or cardiovascular complications. Seven hundred eightyfour (73.1%) of 1073 patients were given autologous blood; 151 (14.1%) patients also required allogeneic blood.CONCLUSION: The onset of anemia (6.5%) was the main contraindication for continuing the PABD program: incidence increased with age. PABD in connection with elective surgery is both feasible and effective in a high percentage of elderly patients.
Genomic characterization of the Kidd blood group gene:different molecular basis of the Jk(a–b–) phenotypein Polynesians and Finns
Authors: Irshaid N.M. , Henry S.M. , Olsson M.L. 
Published: March 2003

BACKGROUND: The clinically important Kidd (JK) blood group antigens are carried by the urea transporter in red cells. The rare Jk(a–b–) phenotype can be caused by homozygosity at the JK locus for a silent allele, Jk. This phenotype has been recorded in many ethnic groups, but it is most abundant among people originating from the Polynesian Islands and Finland. The molecular basis for Jk(a–b–) is unknown in these populations.STUDY DESIGN AND METHODS: Blood samples from individuals of Swedish, Polynesian, and Finnish origin were collected and characterized by routine JK blood group serology and JK genotyping. Genomic DNA covering the exons and intervening introns of the JK gene coding region was amplified by polymerase chain reaction, and fragments were directly sequenced.RESULTS: Exon and partial intron sequences in the coding region of the JK gene were determined. Finnish and Polynesian Jk alleles were analyzed; the only deviations from consensus were a splice‐site mutation (G→A) in Polynesians, causing skipping of exon 6, and a T871C substitution predicted to disrupt a potential N‐glyco‐sylation motif (NSS→NSP) in Finns. Methods for rapid detection of silent Jk alleles were developed for clinical application.CONCLUSION: Polynesians and Finns have two different molecular alterations in their Jk alleles, both of which can now be determined by polymerase chain reaction.
White cell apoptosis in platelet concentrates
Authors: Frabetti F. , Tazzari P.L. , Musiani D. , Bontadini A. , Matteini C. , Roseti L. , Tassi C. , Viggiani M. , Marini M. , Conte R. 
Published: March 2003

BACKGROUND: The aim of the present study was the evaluation of the apoptosis in residual white cells (WBCs) contained in platelet concentrates (PCs) and of the relationship of this apoptosis with the concentration of inflammatory cytokines in the medium and with platelet activation.STUDY DESIGN AND METHODS: Three independent methods were used to evaluated apoptosis in WBCs present in 9 PCs, either from single donors by apheresis (SD‐PCs) or from pooled buffy coats (BC‐PCs). All PCs were divided in two parts, one of which was irradiated. PCs were stored up to 4 days at room temperature, and samples were withdrawn daily for analysis of apoptosis, of platelet activation (surface and soluble CD62P), and of cytokine concentration (interleukin [IL]‐1α, IL‐1β, IL‐6, IL‐8, and tumor necrosis factor α).RESULTS: Apoptosis was found to occur with storage in both irradiated and nonirradiated units. Platelet activation increased with storage time and was higher in BC‐PCs. The amount of released cytokines was rather variable among PC units. Only IL‐8 was consistently found to increase with storage time.CONCLUSIONS: Apoptosis of residual WBCs occurred in PC units as a function of storage time. The amount and the time course of apoptosis seem to correlate with IL‐8 release rather than with platelet activation or with the occurrence of febrile nonhemolytic transfusion reactions.
Molecular mechanisms that lead to reduced expression of Duffy antigens
Authors: Yazdanbakhsh K. , Rios M. , Storry J.R. , Kosower N. , Parasol N. , Chaudhuri A. , Reid M.E. 
Published: March 2003

BACKGROUND: In the Duffy blood group system, the null phenotype Fy(a–b–) has been classically associated with a mutated GATA box, while the Fyx phenotype weak Fyb is associated with Arg89Cys and Ala100Thr mutations. This report assesses the prevalence of the Duffy GATA box and the Fyx‐associated mutations in white and African American (black) donors and investigates the molecular mechanism underlying the Fyx phenotype.STUDY DESIGN AND METHODS: PCR RFLP Duffy genotyping was performed on blood samples from blacks and whites. Duffy antigen expression (Fya, Fyb, Fy6, Fy3) on RBCs was measured by flow cytometry. By site‐directed mutagenesis, the relevance of each Fyx‐associated mutation to Duffy (mRNA, antigen, and protein) expression was analyzed in transfectants by Northern blotting, flow cytometry, and immunoblotting.RESULTS: The mutated GATA box occurred at a high allele frequency (0.8) in blacks and was rare among whites. Conversely, the Fyx‐associated mutations were absent in blacks, but present in 3.5 percent of whites. By flow cytometry, Duffy antigens (Fya or Fyb, Fy6 and Fy3) showed a dosage effect in RBC samples that were transcriptionally silenced by the GATA box mutation in one allele. By contrast, the reduced (10%) Duffy protein in Fyx RBCs was shown by heterologous expression analysis not to be due to reduced RNA levels, but to protein instability caused by Arg89Cys.CONCLUSIONS: R educed Duffy expression can result from mutations affecting transcription (mutated GATA box in one allele) or instability of the translated protein (Arg89Cys). The frequencies of these mutations vary among populations.
Identification of a novel hybrid glycophorin gene encoding GP.Hop
Authors: Storry J.R. , Poole J. , Condon J. , Reid M.E. 
Published: March 2003

BACKGROUND: The GP.Hop (Mi.IV) phenotype expresses the MNS low‐incidence antigens Mur, Hop, TSEN, MINY, and MUT. Because serologically similar MNS phenotypes expressing some or all of these antigens were shown to be carried by hybrid GP(B‐A‐B) proteins, it was proposed that a similar protein would be found for GP.Hop. The identification of a second GP.Hop propositus (ES) initiated a study to determine the molecular basis of this phenotype.STUDY DESIGN AND METHODS: Serologic tests and immunoblotting analysis with glycophorin‐specific antibodies were performed. GYPB, the gene encoding the GPB protein, was cloned and sequenced after reverse transcription PCR amplification of total RNA isolated from ES. GYPB‐specific primers encompassing GYPB pseudoexon 3, intron 3, and exon 4 were also used to clone and sequence genomic DNA from ES and MH, the original GP.Hop proband.RESULTS: Serologic and immunochemical data confirmed that ES's RBCs carried antigens associated with the GP.Hop phenotype. Sequencing of ES's cDNA demonstrated the presence of genes predicted to encode s‐specific GPB and an S‐specific GP(B‐A‐B) hybrid in which the 3′ end of GYPB pseudoexon 3 had been replaced by a short nucleotide sequence from exon 3 of the GPA gene (GYPA). The hybrid nucleotide sequence contained sequence motifs previously shown to be required for the expression of the Mur, Hop, TSEN, MINY, and MUT, which is consistent with their presence as detected serologically. Genomic DNA analysis found that the crossover point in GYPB pseudoexon 3 was identical in ES and MH.CONCLUSIONS: The GP.Hop phenotype is produced by a hybrid GP(B‐A‐B) protein caused by a DNA insertion of GYPA into GYPB. The composition of the hybrid protein is GPB(1‐26)‐GPψB(27‐50)‐GPA(51‐58)‐GPBS(59‐103).
Compodock, a new device for sterile docking
Authors: Van Der Meer P.F. , Biekart F.T. , Pietersz R.N.I. , Rebers S.P.H. , Reesink H.W. 
Published: March 2003

BACKGROUND: A new device for sterile docking, the Compodock (Fresenius NPBI Transfusion Technology), was developed for connecting PVC tubing for medical use while maintaining sterility.STUDY DESIGN AND METHODS: Sterility of the connections was assessed by welding tubing with a heavy exterior contamination with Bacillus subtilis spores and also by welding in an environment contaminated with aerosols of B. subtilis. Tubing was either dry or liquid‐filled (“wet”) and had various diameters. Bacterial culture medium was flushed through the welded area and subsequently cultured. Tensile strength was measured, and, under semi‐routine conditions, Compodock was tested for user friendliness and speed.RESULTS: None of the cultures of welded tubing with exterior contamination showed growth, neither the dry‐dry (n = 434) nor the wet‐wet connections (n = 622). Cultures were also negative for welds made in the contaminated environment (dry‐dry, 67; wet‐wet, 55). Tensile strength complied fully with ISO 3826 standards (that is, a force of 20 newtons [N] for 15 sec), with a mean maximal strength ranging from 73 to 100 N, depending on diameter and content of the tubing. The semi‐routine handling was regarded as good: welds were easily opened; there were clear instructions and error warnings; and the processing time averaged 52 seconds.CONCLUSION: The Compodock is able to maintain a functionally closed system, with maintenance of sterility, despite heavy exterior bacterial contamination; tensile strength conformed to ISO standards. Compodock is suitable for routine implementation in the blood bank.
Investigation of porcine parvovirus among persons with hemophilia receiving Hyate:C porcine factor VIII concentrate
Authors: Soucie J.M. , Erdman D.D. , Evatt B.L. , Anderson L.J. , Török T.J. , El‐Jamil M. , Barnhart E. , Tepper M. , Burrill H.N. , Pickett A.M. , Mengeling W.L. 
Published: March 2003

BACKGROUND: Porcine clotting factor has been used for more than 15 years to treat severe bleeding episodes in persons with hemophilia who have antibodies to human clotting factor. In 1996, QC procedures revealed for the first time the presence of porcine parvovirus (PPV) in the product. This report describes an investigation to determine the extent of product contamination and to evaluate past recipients of porcine clotting factor (Hyate:C, Speywood Biopharm) for evidence of PPV infection.STUDY DESIGN AND METHODS: Stored specimens from 22 lots of previously released Hyate:C were tested for the presence of PPV DNA by PCR and nested PCR assays. Serum specimens from 98 recipients of Hyate:C and 24 controls who did not receive Hyate:C were tested for PPV antibodies by an immunofluorescence assay.RESULTS: PPV DNA was detected in product from 21 of the 22 lots of Hyate:C, primarily by nested PCR testing. In contrast, none of the serum specimens from the 98 Hyate:C recipients tested positive for PPV IgG antibodies.CONCLUSION: The risk of human disease from percutaneous exposure to low levels of PPV seems to be low. Nevertheless, the theoretical risk of human infection with PPV has led to manufacturing changes, including PCR screening of all porcine plasma, which are designed to eliminate this risk.
RBC transfusion and postoperative length of stay in the hospital or the intensive care unit among patients undergoing coronary artery bypass graft surgery: the effects of confounding factors
Authors: Vamvakas E.C. , Carven J.H. 
Published: March 2003

BACKROUND: Data on the independent association between perioperative allogeneic blood transfusion (ABT) and postoperative length of stay at the hospital or in the intensive care unit (ICU) are sparse.STUDY DESIGN AND METHODS: The records of 421 consecutive patients undergoing coronary artery bypass graft (CABG) operations at the Massachusetts General Hospital were reviewed. The effect of perioperative ABT in explaining the variation in the postoperative length of stay (LOS) at the hospital or in the ICU was calculated after adjustment for the effects of 20 confounding factors that pertained to severity of illness, difficulty of operation, and risk of postoperative wound infection or pneumonia.RESULTS: Postoperative LOS averaged (mean ± SE) 8.0 ± 0.3 days in the hospital and 50.0 ± 4.1 hours in the ICU. After adjustment for the effects of confounding factors, the postoperative length of hospitalization increased by 0.837 percent (95% CI, 0.249‐1.425%) per RBC unit transfused (p<0.001), and the postoperative length of stay in the ICU increased by 0.873 percent (95% CI, −0.068‐1.814%) per RBC unit transfused (p<0.10).CONCLUSION: Allogeneic blood transfusion was independently associated with longer postoperative stays in the hospital or the ICU, but the observed independent association is perhaps too small to be clinically relevant. This independent association may be due to a relationship between ABT and a higher incidence of septic complications of surgery, or it may reflect the function of blood transfusion as a surrogate marker for severity of illness.
Detection of HLA antibodies by using flow cytometry and latex beads coated with HLA antigens
Authors: Moses L.A. , Stroncek D.F. , Cipolone K.M. , Marincola F.M. 
Published: March 2003

BACKGROUND: Detection of HLA class I antibodies in sera is needed in various clinical situations. The standard method for detecting HLA class I antibodies is the complement‐dependent lymphocytotoxicity (CDC) assay, but solid‐phase assays are now available.STUDY DESIGN AND METHODS: This study assessed the ability of a flow cytometric assay using latex beads coated with HLA class I antigens to detect HLA class I‐specific antibodies. The CDC assay was compared with the pooled‐bead assay for the detection of HLA class I antibodies. Thirty‐one randomly selected serum samples previously tested by CDC assay were tested with pooled beads and analyzed by flow cytometry. Twenty‐seven additional serum samples, chosen by clinical criteria and CDC assay results, were tested against the pooled beads. Next, samples from six patients from whom three or more serum samples were drawn on consecutive days were tested with both methods. Finally, serum samples that were proved positive by both methods were tested with selected beads coated with antigens from a single person.RESULTS: Among the randomly selected serum samples, there was 90‐percent agreement between the two assays. There was 96‐percent agreement between the two assays of the 27 samples that were selected by clinical criteria and CDC assay results. Testing the sera with individual beads suggested that the HLA class I antibodies react with beads expressing the corresponding HLA antigen and beads expressing antigens in the same cross‐reactive group.CONCLUSION: The pooled‐bead assay can be used as an alternative method for detecting HLA class I antibodies. However, if the specificity of the HLA class I antibody is required, another assay must be used.
Differential expression of the Duffy antigen receptor for chemokines according to RBC age and FY genotype
Authors: Woolley I.J. , Hotmire K.A. , Sramkoski R.M. , Zimmerman P.A. , Kazura J.W. 
Published: March 2003

BACKGROUND: The Duffy (Fy) blood group (also known as Duffy antigen receptor for chemokines, or DARC) may be involved in regulation of the level of circulating proinflammatory chemokines, and it is an obligatory receptor on RBCs for the human malaria parasite Plasmodium vivax.STUDY DESIGN AND METHODS: Because quantification of Fy expression by using RBCs of various ages will not detect acute changes associated with inflammatory states, and because P. vivax exclusively invades reticulocytes, a flow cytometric method was developed to measure the level of surface expression of Fy. Reticulocytes and mature RBCs from persons with different genotypes (GATA‐1 T→C promoter mutation at nt –46; FY*A and FY*B in the ORF) were used.RESULTS: Expression of the Fy6 epitope, which is required for P. vivax invasion, was 49 ± 19 percent higher on reticulocytes than on mature RBCs, regardless of donor genotype (p<0.0001). Fy6 levels were approximately 50 percent lower in persons who were heterozygous for the GATA‐1 promoter mutation and were significantly lower on reticulocytes and mature RBCs of the FY*B/FY*B genotype than on those of the FY*A/FY*A or FY*A/FY*B genotype.CONCLUSION: Fy has greater expression on reticulocytes than on mature RBCs in flow cytometry. This method may be useful in further studies of this antigen, such as characterization of reticulocytes and RBC phenotypes across populations, in response to chemokine regulation, and in the context of susceptibility to P. vivax and other parasites.