bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct immunomagnetic method for CD34+ cell selection from cryopreserved cord blood grafts for ex vivo expansion protocols
Authors: Querol S. , Capmany G. , Azqueta C. , Gabarró M. , Fornas O. , Martín‐Henao G.A. , García J. 
Published: March 2003

BACKGROUND: Cord blood is a useful source of HPCs for allogeneic transplantation. HPC ex vivo expansion of a cord blood graft has been proposed as a way to increase the speed of engraftment and thus to reduce the occurrence of transplantation‐related complications.OBJECTIVE: The purpose of this study was to optimize a method for CD34+ cell selection of thawed cord blood grafts under clinical grade conditions, intended for application in a static, serum‐free expansion culture.MATERIAL AND METHODS: Twelve samples were thawed and washed with dextran, albumin, and rHu‐deoxyribo‐nuclease I (RHu‐DNase) to avoid clumping. CD34+ cells were selected by using a sensitized immunomagnetic bead and 9C5 MoAb complex. A buffer containing rHu‐DNase, citrate, albumin, and immunoglobulin in PBS was used during the procedure. CD34+ cells were eluted and detached by using an immunomagnetic cell selection device. Cells from the enriched fraction were cultured for 6 days in serum‐free medium supplemented with rHu‐SCF, rHu‐IL‐3, rHu fetal liver tyrosine kinase 3 ligand, and rHu thrombopoietin (50 ng/mL each). Cells were expanded in well plates and in two semipermeable bags.RESULTS: A mean of 1.94 × 106 (± 1.55) CD34+ cells was obtained, yielding a CD34+ cell recovery of 52 ± 12 percent. Nonspecific loss of CD34+ cells was 32 ± 10 percent. CFU–GM and BFU–E/CFU‐Mixed recoveries were 33 ± 15 percent and 27 ± 12 percent, respectively. CD34+ cells obtained were functionally comparable with fresh CD34+ cells selected for clonogenic potential. The capacity for expansion was not significantly different in the two types of bags studied. HPCs in wells were expanded 33 ± 14‐fold for CD34+ cells and 42 ± 19‐fold for overall colonies. The expansion rates observed in wells were significantly superior to those obtained in bags.CONCLUSION: The feasibility of a clinical‐scale cord blood selection procedure based on a direct immunomagnetic method after thawing, followed by an ex vivo expansion culture using semipermeable bags, is shown. After 6 days of expansion, it was possible to generate a 9‐fold increase in CD34+ cells, a 6‐fold increase in CFU–GM and a 13‐fold increase in BFU–E/CFU–Mixed colonies.
Acute intravascular hemolysis secondaryto out‐of‐group platelet transfusion
Authors: Larsson L.G. , Welsh V.J. , Ladd D.J. 
Published: March 2003

BACKGROUND: Acute intravascular hemolysis is rarely associated with platelet transfusion. Out‐of‐group single‐donor platelets may cause hemolysis if the donor has high‐titer ABO hemagglutinins.CASE REPORT: A 44‐year‐old woman, blood group A, was recently diagnosed with acute myeloid leukemia and was receiving chemotherapy. After the transfusion of apheresis platelets from a group O donor, back pain, hemoglobinuria, and hemoglobinemia developed, and her Hb dropped by 2.3 g per dL, despite the transfusion of 2 units of RBCs.RESULTS: Investigation revealed acute intravascular hemolysis with a positive DAT due to anti‐A1 on her RBCs. The donor's titer of anti‐A1 was greater than 16,000.CONCLUSION: Review of published cases raises the possibility that hemolytic reactions to out‐of‐group platelets may be more frequent since the use of apheresis platelets has increased.
Hepatitis B virions isolated with antibodies to the pre‐S1 domain reveal occult viremia by PCR in Alaska Native HBV carriers who have seroconverted
Authors: Gandhi M.J. , Yang G.G. , McMahon B.J. , Vyas G.N. 
Published: March 2003

BACKGROUND: Occult viremia occurring before the appearance of HBsAg or after the disappearance of HBsAg is detectable by gene amplification technologies whose efficiency depends on nucleic acid preparation.STUDY DESIGN AND METHODS: To isolate HBV DNA from viremic plasma, immunoaffinity capture (IAC) of intact HBV with biotinylated pre‐S1 antibodies coupled to streptavidin‐coated magnetic beads was evaluated. IAC was compared with a silica‐gel method (Qiagen [QSG]) and its two modifications wherein the samples were heated with lysis buffer at 60oC for 10 minutes (QSG‐60) or at 58°C for 60 minutes with proteinase‐K (QSG‐PK). Each HBV DNA sample was tested by heminested PCR amplification of the HBV gene sequences. A total of 36 coded serum samples were tested, including three HBsAg‐positive controls and 33 former chronic HBV carriers who had seroconverted (developed antibody to HBsAg [anti‐HBs]). Commercially available seroconversion panels (PHM 907, 911, and 922) were similarly tested for window‐period viremia.RESULTS: In the 33 former chronic HBV carriers who had seroconverted, IAC revealed HBV DNA in 17 samples, whereas it was revealed in only 11 samples by QSG‐PK (p = 0.031), 10 by QSG‐60 (p = 0.016), and 9 by QSG (p = 0.0078). However, HBV DNA was not amplified from the 17 samples at 1‐in‐10 dilutions; thus, they were considered to have low‐level viremia. IAC revealed HBV DNA as early as or earlier than the other methods in PHM 907, 911, and 922 panels.CONCLUSION: IAC is apparently an optimal method of sample preparation for amplification of HBV DNA in patients in the pre‐HBsAg window period, and for detecting low‐level viremia persistent in several individuals who were former chronic HBV carriers who had seroconverted (developed anti‐HBs).
Performance of second‐ and third‐generationRIBAs for confirmation of third‐generationHCV EIA‐reactive blood donations
Authors: Tobler L.H. , Lee S.R. , Stramer S.L. , Peterson J. , Kochesky R. , Watanabe K. , Quan S. , Polito A. , Busch M.P. ,   for the Retrovirus Epidemiology Donor Study
Published: March 2003

BACKGROUND: Licensure of an enhanced HCV screening assay (HCV 3.0 EIA) without concurrent licensure of a complementary supplemental assay (i.e., RIBA HCV 3.0 strip immunoblot assay [RIBA‐3]) decoupled screening and supplemental testing. In March 1998, the FDA Center for Biologics Evaluation and Research (CBER) recommended the use of RIBA‐3 on RIBA HCV 2.0 strip immunoblot assay (RIBA‐2)‐indeterminate units screened with HCV EIA 3.0.STUDY DESIGN AND METHODS: The sensitivity of RIBA‐2 and RIBA‐3 was compared in tests on HCV 3.0 EIA‐repeatably reactive (RR) units identified immediately after the implementation of HCV 3.0 EIA screening. Two protocols were evaluated: parallel testing of HCV 3.0 EIA‐RR units by RIBA‐2 and RIBA‐3 and reflex testing of HCV 3.0 EIA‐RR and RIBA‐3‐confirmed‐positive units by RIBA‐2. All specimens with discordant RIBA‐2 and RIBA‐3 results and a representative sampling with concordant RIBA results were tested by PCR.RESULTS: In the parallel testing protocol, 99,777 donations were screened, with 245 HCV 3.0 EIA‐RR specimens included in the study. Of 166 RIBA‐2‐positive samples, 165 tested positive in RIBA‐3 (1 sample reacted to the control superoxide dismutase antigen in RIBA‐3). Thirty‐two (74%) of 43 RIBA‐2‐indeterminate specimens and 4 (11%) of 36 RIBA‐2‐negative specimens tested positive in RIBA‐3. HCV RNA was identified in 5 (16%) of 32 RIBA‐2‐indeterminate/RIBA‐3‐positive donations, as well as in 26 (70%) of 37 concordant RIBA‐2/RIBA‐3‐positive donations. In the reflex testing protocol, 292,459 donations were screened, with 709 HCV 3.0 EIA‐RR specimens included in the study. RIBA‐3 testing yielded 517 (73%) positive specimens, of which 50 (9.7%) tested indeterminate and 15 (2.9%) tested negative in RIBA‐2. Among the RIBA‐discordant specimens, 10 (20%) RIBA‐2‐indeterminate specimens and 1 (7%) RIBA‐2‐negative specimens tested positive in PCR; in comparison, 60 (77%) of 78 concordant RIBA‐2/RIBA‐3‐positive units tested positive in PCR.CONCLUSIONS: RIBA‐3 is significantly more sensitive than RIBA‐2 in testing of HCV 3.0 EIA‐screened donations. During the review process of this manuscript, the FDA licensed the RIBA‐3 test.
Description of serologic features in autoimmune lymphoproliferative syndrome
Authors: Carter L.B. , Procter J.L. , Dale J.K. , Straus S.E. , Cantilena C.C. 
Published: March 2003

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a recently recognized and rare disorder associated with inherited defects in the Fas gene or other regulators of lymphocyte apoptosis. It is characterized by massive lymphadenopathy; splenomegaly; autoimmunity including episodes of immune hemolytic anemia, thrombocytopenia, and neutropenia.1 The serologic basis for immune cytopenias associated with ALPS has not been previously characterized.STUDY DESIGN AND METHODS: RBC, granulocyte, and platelet serologies for ALPS patients and hepatitis C patients were assessed. Medical records were reviewed for clinical, immunologic, serologic, and transfusion history. Testing included: DAT; serum screening for antibodies to RBCs, granulocytes, platelets, cardiolipin, penicillin‐coated RBCs, and human leukocyte antigens; antibody identification and IgG subclass; RBC phenotype.RESULTS: In a cohort of 11 patients with apoptosis defects (eight with heterozygous Fas gene mutations); many had histories of hemolytic anemia (7), thrombocytopenia (4), and/or leukopenia (11); nine received steroid therapy, seven underwent splenectomy; five had been remotely transfused. On the basis of serologic testing even when they were clinically stable, nine had positive DATs; two had alloantibodies; 6 had IgG and/or IgM antibodies to cardiolipin; seven had platelet‐directed antibodies; three had granulocyte‐directed antibodies; none had HLA antibodies.CONCLUSIONS: Nearly all ALPS patients have antibodies directed against one or more hematopoietic cell lineages. Serologic testing is critical in the evaluation of these individuals and when transfusion is indicated, red cells that are matched for clinically significant C, E, and K antigens should be considered.
Evaluation of the effectiveness of targeted lookback for HCV infection in the United States—interim results
Authors: Culver David H. , Alter Miriam J. , Mullan Robert J. , Margolis Harold S. 
Published: March 2003

BACKGROUND: As part of a nationwide program to identify persons at increased risk for HCV infection, persons who received blood from donors who later tested positive for anti‐HCV are being directly notified.STUDY DESIGN AND METHODS: In December 1999, all 198 blood collection establishments (BCEs) and 5442 hospital transfusion services (TSs) in the United States were surveyed by mailed questionnaire to evaluate their progress in carrying out this notification.RESULTS: Eighty‐one percent of the BCEs and 64 percent of the TSs responded. After correcting for nonresponse, an estimated 98,484 components at potential risk for transmitting HCV, according to previous testing of multiantigen‐screened donors, were identified nationwide, of which 85 percent had been transfused to recipients. Lookback for these recipients was completed for 80 percent, of whom 69 percent had died. Of those living, 78 percent were successfully notified. An estimated 49.5 percent of those notified were tested; 18.9 percent of those tested were anti‐HCV positive, and 32 percent of that group knew they were positive before notification. On the basis of an 85.5 percent reported completion rate for component notifications back through 1988, an estimated 1520 persons will have been newly identified as anti‐HCV‐positive when lookback related to multiantigen screening of donors is completed.CONCLUSION: Targeted lookback related to previous multiantigen screening of donors will identify <1 percent of the estimated 300,000 HCV‐positive persons in the United States who may have acquired their infection via blood transfusion.
Growth of bacteria in inoculated platelets: implications for bacteria detection and the extension of platelet storage
Authors: Brecher Mark E. , Holland Paul V. , Pineda Alvaro A. , Tegtmeier Gary E. , Yomtovian Roslyn 
Published: March 2003

BACKGROUND: Recent reports from Europe have advocated the use of bacterial culturing of platelets on Day 2 or 3 of storage to extend the shelf life of platelets to 7 days, thereby reducing the outdating of platelets and preserving a limited medical resource. To assess the optimal timing, the necessary sensitivity, and the possible efficacy of bacterial detection, the bacterial growth characteristics were reviewed in 165 platelet units, each inoculated on the day of collection with one of the following organisms: Bacillus cereus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia marcescens, Staphylococcus aureus, and Staphylococcus epidermidis from four previously published studies.STUDY DESIGN AND METHODS: Quantitative culture data from inoculated platelet concentrates from five sites and four studies were combined into one database and analyzed for bacterial concentration thresholds (≥101, ≥102, ≥103, ≥104, ≥105 CFU/mL) by day of storage.RESULTS: All examples of B. cereus, P. aeruginosa, K. pneumoniae, S. marcescens, and S. aureus had concentrations ≥102 CFU per mL by Day 3 after inoculation. By Day 4, all units with these organisms contained ≥105 CFU per mL. Units contaminated with S. epidermidis showed slower and more varied growth. By Day 3 after inoculation, 81.3 percent had 102 CFU per mL. By Day 4 after inoculation, 46 (95.8%) of 48 units had concentrations ≥102 CFU per mL.CONCLUSION: These experiments suggest that an assay capable of detecting 102 CFU per mL on Day 3 of storage would detect the vast majority of bacterially contaminated platelet units, prevent many cases of platelet‐associated bacterial sepsis, and provide a scientific basis for the extension of the current platelet storage time. It would be expected that a rare, slow‐growing organism could escape such a detection scheme.
RBC autoantibodies in autoimmune lymphoproliferative syndrome
Authors: Stroncek David F. , Carter Laura B. , Procter Jo L. , Dale Janet K. , Straus Stephen E. 
Published: March 2003

BACKGROUND: Patients with autoimmune lymphoproliferative syndrome (ALPS) have an autosomal dominant genetic defect that affects lymphocyte apoptosis and is associated with chronic nonmalignant lymphadenopathy, splenomegaly, and autoimmunity, particularly affecting RBCs, WBCs, and platelets.STUDY DESIGN AND METHODS: DATs were performed on 34 consecutive patients with ALPS and 37 of their clinically unaffected relatives. The effects of age, sex, race, and immunoglobulin levels on the incidence of autoantibodies and clinical hemolysis were assessed.RESULTS: The DAT was positive in 21 (62%) of ALPS patients but in only 1 (3%) of their relatives (p = 0.001). The DAT reacted because of IgG alone in 43 percent, complement alone in 5 percent, and IgG plus complement in 19 percent; 33 percent of the patients′ cells had a positive reaction with polyspecific reagent only. All 10 ALPS patients with a history of hemolytic anemia had a positive DAT. Sixty percent of them had only IgG on their cells, 30 percent had IgG and complement, and 10 percent reacted only with polyspecific reagent. Of the 11 patients with a positive DAT and no history of hemolytic anemia, IgG alone was present in 27 percent, complement alone in 9%, and IgG plus complement in 9 percent; 55 percent had positive DATs only with polyspecific reagent. Among ALPS patients, those with a positive DAT had greater quantities of cells with increased α and β T‐cell receptors that phenotyped as CD4–CD8– and higher IgG levels.CONCLUSIONS: The DAT results in ALPS patients are most similar to those found in warm autoimmune hemolytic anemia. The DAT is useful to distinguish affected and unaffected persons within an ALPS family.
Infectivity of blood from PCR‐positive, HBsAg‐negative, anti‐HBs‐positive cases of resolved hepatitis B infection
Authors: Prince Alfred M. , Lee Dong‐Hun , Brotman Betsy 
Published: March 2003

BACKGROUND: Numerous reports have noted the existence of sera, particularly from resolving cases of HBV infection, that are positive for HBV DNA by PCR, despite being negative for HBsAg and IgM anti‐HBc. If such blood is infective and detectable by HBV NAT screening, it seems desirable to introduce such screening for transfused blood.STUDY DESIGN AND METHODS: Three chimpanzees were inoculated with serum and lymphocytes from three patients who were HBV DNA PCR positive, but HBsAg negative. The animals were tested over a period of 15 months for HBsAg, anti‐HBs, anti‐HBc, and HBV DNA by PCR.RESULTS: All animals remained uninfected.CONCLUSION: Small amounts of plasma and MNCs from HBV DNA‐positive HBsAg‐negative blood do not appear to be infectious; however, further studies with larger volumes of inoculum should be conducted.
Accuracy of predonation Hct sampling affects donor safety, eligibility, and deferral rates
Authors: Wood Erica M. , Kim Debora M. , Miller John P. 
Published: March 2003

BACKGROUND: Safe blood donation depends upon reliable predonation Hct screening. Earstick (ES) capillary samples are frequently used, but they may not be accurate.STUDY DESIGN AND METHODS: Predonation ES and fingerstick (FS) and postdonation venous Hct results were compared in 1960 whole‐blood and 210 apheresis donors. The validity of using postdonation venous samples to evaluate predonation ES and FS Hct was assessed in 20 whole‐blood donors. The impact of Hct screening method on donor Hct deferrals was examined during periods when either ES or FS sampling was used exclusively.RESULTS: All donors were eligible to donate on the basis of a predonation capillary Hct of ≥38 percent. In venous samples obtained immediately after donation, 36 percent of whole‐blood donors had a Hct <38 percent. With correction for a decrease of approximately 2 Hct units during donation, 20 percent of these donors had a predonation Hct <38 percent. The lowest venous Hct was 23.1 percent. FS samples showed better correlation with venous Hct. Hct discrepancies were similar for apheresis donors. Hct deferrals were significantly higher with FS sampling, especially among women.CONCLUSION: Hct determinations from ES samples overestimate venous Hct. Fingerstick samples are more sensitive in detecting anemia. The accuracy of predona‐tion Hct sampling has implications for donor safety, eligibility, and deferral rates.
Inverse expression of Pk and Luke blood group antigens on human RBCs
Authors: Cooling Laura L. , Kelly Kathleen 
Published: March 2003

BACKGROUND: Luke (LKE) is a high‐frequency RBC antigen, related to the P blood group system. A LKE‐negative phenotype is found in 1 to 2 percent of donors and may be associated with increased Pk. Because Pk and similar glycolipids are receptors for shiga toxin on cell membranes, a LKE‐negative phenotype could have implications for infections by Shigella dysenteriae and enterohemorrhagic Escherichia coli.STUDY DESIGN AND METHODS: Volunteer donors (n = 257) were serologically typed for LKE with a LKE MoAb, MC813‐70. LKE‐strong‐positive, LKE‐weak‐positive and LKE‐negative RBCs were analyzed for Pk, P, LKE, and shiga toxin binding by immunofluorescence flow cytometry, high‐performance thin‐layer chromatography, scanning densitometry, and high‐performance thin‐layer chromatography immunostaining.RESULTS: Among Iowa donors, 78.6 percent were LKE‐strong‐positive, 20.2 percent were LKE‐weak‐positive, and 1.2 percent were LKE‐negative. There was an inverse expression of Pk and LKE on RBCs. Pk expression was increased on LKE‐negative RBCs and was associated with increased shiga toxin binding. A LKE‐active glycolipid was identified in the ganglioside fraction of LKE‐strong‐positive RBCs.CONCLUSION: A LKE‐negative phenotype is associated with increased expression of Pk on RBCs. Differences in Pk and LKE expression may play a role in host susceptibility to infection with S. dysenteriae and E. coli.
Comparison of the sensitivity of NAT using pooled donor samples for HBV and that of a serologic HBsAg assay
Authors: Sato Shinichiro , Ohhashi Wataru , Ihara Hiromi , Sakaya Shinichi , Kato Toshiaki , Ikeda Hisami 
Published: March 2003

BACKGROUND : Studies were conducted using samples from early and late‐stage HBV‐infected persons to determine the pool size at which PCR had better sensitivity than a sensitive HBsAg chemoluminescence immunoassay (CLIA‐HBsAg).STUDY DESIGN AND METHODS: HBV seroconversion panels were tested for HBsAg by CLIA and for HBV DNA by nested PCR (95% hit rate: 100 copies/mL); PCR was carried out at various dilutions. HBV serologically positive samples that were detected from the simultaneous screening of 540,161 routine whole‐blood donations using CLIA‐HBsAg and agglutination assays were also characterized for additional markers of HBV infection.RESULTS: In 9 of 10 HBV seroconversion panels, PCR had better sensitivity than CLIA‐HBsAg at dilutions of 1‐in‐25 or lower. Of 65 CLIA‐only confirmed‐positive donor samples (agglutination assay‐negative), 8 represented early infection, 2 of which were PCR positive at a 1‐in‐50 dilution but negative at a 1‐in‐100 dilution. Only 2 of 47 samples from probable late‐stage HBV infection that were positive on CLIA only were PCR positive with 0.1‐mL sample volume and the S‐region primer; the remaining 45 samples required a 1.0‐mL sample input and C‐region primer for increased PCR positivity. The remaining 10 CLIA‐only confirmed‐positive donor samples were from HBV vaccine recipients. None of the 12 CLIA‐ and HBsAg‐negative donor samples that were strongly anti‐HBc reactive could be detected by PCR at any dilution; all 12 were PCR positive when undiluted, but 4 required a 1.0‐mL input volume for PCR positivity.CONCLUSION: For the detection of samples representing early‐stage HBV infection, PCR at dilutions of 1‐in‐25 or lower (equivalent to a pool of ≤25 members) had greater sensitivity than CLIA‐HBsAg. In contrast, samples from late‐stage HBV infection were detected by PCR only with undiluted samples (0.1‐mL or 1.0‐mL input volumes), regardless of CLIA‐HBsAg reactivity. Therefore, although NAT using minipools of 25 donations or less may be effective for the detection of early‐stage HBV infection, it may not be effective for the detection of persistent HBV infection.