ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420749.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420750.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:The pooling of human plasma from many donors for the purpose of manufacturing therapeutic proteins increases the risk of exposing recipients of these proteins to pathogens that may contaminate 1 or a few units included in the pool.Study Design and Methods:This risk is estimated for a range of manufacturing scales that would derive material from a varied number of donors and for a number of hypothetical infectious agents that may exist in the donor population over a wide range of prevalence. Risk is also calculated both for recipients of single doses of a plasma protein and for those who depend on long‐term treatment with plasma derivatives.Results:Risk of exposure increases with pool size and the prevalence of the agent in question and accumulates with repeated treatments with material manufactured from different pools.Conclusion:Reducing pool size would at best decrease this risk in proportion to the reduction in manufacturing scale. However, for individuals requiring repeated or continuous treatments, the risk of exposure to all but the rarest infectious agents would be only minimally affected, even by large reductions in manufacturing scal

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420751.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non‐B, non‐C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti‐HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients.Study Design and Methods:Data on blood donors and recipients enrolled in the Transfusion‐Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti‐HBc testing of donors and anti‐HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients.Results:For HCV cases, donor ALT alone (at ≥ 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti‐HBc alone (at ≥ 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected].Conclusion:The indirect tests proved to be equal in sensitivity to the first‐generation anti‐HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti‐HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepat

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420752.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:It is important to compare the incidence of bacterial contamination of components collected from the peripheral blood or bone marrow (BM), as well as of components processed with or without cell selection or depletion, and to evaluate the sequelae of such contamination.Study Design and Methods:Bacterial contamination rates were compared in 1380 untreated autologous peripheral blood progenitor cells (PBPCs), 291 untreated autologous BM samples, 916 monoclonal antibody (MoAb)‐treated autologous and allogeneic BM samples, and in 45 autologous PBPC components from which the CD34+ cells were selected. Bacterial cultures were performed at sequential time points during the processing of MoAb‐treated BM.Results:Bacterial contamination was documented in 44 of 2632 components from 1593 patients (1.67% of components, 2.76% of patients) before cryopreservation. Although only 0.65% of untreated PBPCs were contaminated before cryopreservation, each patient was more likely to have given a contaminated PBPC component than a contaminated BM component (2.41% vs. 0%, p<0.01). Bacterial contamination of MoAb‐treated BM was greater during or after manipulation than it was before (2.33% vs. 0.77%, p<0.05). At thawing, contamination was documented in 42 (1.97%) of 2136 components cultured. Ten (13.7%) of 73 patients who received hematopoietic progenitor cells that were contaminated before cryopreservation or at thawing developed fever or positive blood cultures within 48 hours of transfusion. Fever was associated with bacteremia in two cases, but no irreversible clinical sequelae were noted.Conclusion:These studies suggest that, despite careful attention to sterile procedures, low‐level contamination of hematopoietic stem cell components can be introduced before or during manipulation as well as at thawing, and that standards for monitoring of the procedures for collection, processing, cryopreservation, thawing, and transfusion of hematopoietic progenitor cells are ne

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420753.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:Peripheral blood progenitor cells (PBPCs) rather than bone marrow are used increasingly to provide hematologic reconstitution when transfused after marrow‐ablative chemotherapy. PBPCs often are collected via central venous catheters that have remained in place for long periods of time and that may become infected.Study Design and Methods:The investigators reviewed their 5‐year experience in collecting PBPCs for the prevalence of bacterial contamination. Except for cotrimoxazole therapy given to preventPneumocystis cariinipneumonia, patients were not given antibiotic prophylaxis.Results:Each patient underwent a median of 7 (range, 2–21) PBPC collections; 0.2 percent (3/1040 collections) were culture positive for bacteria (two collections contained coagulase‐negative staphylococci and one containedSerratia marcescens). All culture‐positive collections were discarded; no PBPCs were culture positive at the time of thawing and transfusion.Conclusion:This contamination rate is below that previously reported for bone marrow harvests and platelet concentrate collections. Obtaining PBPCs through large‐bore central venous catheters has not added to the risk of infection in transplant patients. A program of screening in vitro cultures and strict adherence to sterility techniques can result in very low microbiologic contamination and thus obviates the need for prophylactic antimicrobials in the PBPCs and in

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420754.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:Cryopreservation of hematopoietic cells with the rate‐controlled method is used in the majority of centers. In recent years, there has been a trend toward the simplification of the process.Study Design and Methods:A simplified method for cryopreservation was developed with 5‐percent dimethyl sulfoxide (DMSO) as the sole cryoprotectant without rate‐controlled freezing. Experiments were done with progressive concentrations of DMSO, ranging from 0 to 10 percent. With DMSO concentrations from 5‐ to 10‐percent, the best recovery and viability for hematopoietic progenitor cells were observed. Hematopoietic progenitor cells with plasma and 5‐percent DMSO were frozen and stored in a −80° C mechanical freezer. Ten patients with solid and hematologic malignancies underwent transplantation with autologous hematopoietic progenitor cells.Results:The median number of transfused mononuclear cells and CD34+ cells was 3.70 (3.1–8.2) × 108per kg and 1.70 (0.8‐6.5) × 106per kg, respectively. The median number of transfused colony‐forming units‐granulocyte‐macrophage was 12.45 (3.4–55.3) × 104per kg. All patients showed rapid and sustained engraftment. The mean times to reach a neutrophil count of 0.5 × 109per L and a platelet count of 50 × 109per L were 11.50 ± 1.70 and 13.90 ± 3.98 days, respectively. All patients are alive and without transfusion requirements in complete remission 2 to 8 months after transplantation.Conclusion:This simplified cryopreservation technique will be useful for institutions without rate‐controlled freezing facilities. Moreover, this method diminishes the amount of DMSO infused t

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420755.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:Peripheral blood progenitor cell (PBPC) collection by hemapheresis has become widely used in recent years. For anticoagulation during cytapheresis, citrate solutions, commonly ACD‐A, are used, at a recommended anticoagulant‐to‐whole blood ratio of 1:11 to 1:12. Although the apheresis procedure is generally well tolerated, the most common patient complaints are attributable to transient hypocalcemia, which is a side effect of the citrate anticoagulant. Patients experiencing discomfort due to hypocalcemia are sometimes managed by a decrease in the flow rate of the anticoagulant.Case Reports:Two cases are reported in which seemingly minor reductions in the anticoagulant: whole blood ratio appeared to cause gelation of freezing solution prepared from plasma that was collected in addition to PBPCs for use in the cryopreservation of cells. In both cases, the final ratio of citrate anticoagulant to whole blood was less than 1:12. Gelation occurred when plasma collected under these conditions was used to prepare freezing solution.Conclusion:The addition of heparin to this plasma, or the addition of ACD‐A to correct the anticoagulant:whole blood ratio, prevented the gelation of freezing solution, which suggests that coagulation activation in the autologous plasma specimen was implicated in the subsequent gelation. During cytapheresis for PBPC collection, citrate‐containing anticoagulants should be used at the recommended ratio of 1:12, or with more anticoagulant than usual. Tolerance for a reduced concentration of citrate may be more limited than is generally appreciated. When plasma is collected in addition to PBPCs, heparin should be added to both the cells and the plasma as soon as possible after the collection. Patients undergoing PBPC and stem cell collection should be given supplemental calcium, rather than less anticoagulant, to alleviate the discomfort associated wit

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420756.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:It is known that some “warm”‐reactive autoantibodies are directed against epitopes on the red cell anion exchanger, protein band 3. Some such antibodies (but not all) recognize Wrb. It is also known that Diaand Dibrepresent an amino acid polymorphism of band 3.Study Design and Methods:Autoantibodies from 119 patients were tested against Di(b‐) red cells. Seventy‐four of these autoantibodies were subsequently absorbed with Di(b‐) red cells.Results:All 119 autoantibodies initially reacted with the Di(b‐) red cells, which showed that none contained only anti‐Dib. Among the 74 adsorbed with Di(b‐) red cells, two were found to contain an unadsorbed anti‐Dibcomponent.Conclusion:No example of autoanti‐Dibas the only autoantibody present was found among the 119 samples tested. However, 2 (2.7%) of 74 autoantibodies subjected to adsorption with Di(b‐) red cells were seen to contain an anti‐Dibcomponent. This low incidence of autoanti‐Dibis in marked contrast to the high incidence of autoanti‐Wrb, although both antibodies define epitopes associated with the red

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420757.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Background:Alloantibodies to HPA‐1a (PlA1) are the major cause of neonatal alloimmune thrombocytopenia and posttransfusion purpura and have been implicated in refractoriness to random‐donor platelet transfusions. However, most assays used to phenotype platelets are cumbersome or time‐consuming for large numbers of samples.Study Design and Methods:A simple, competitive (inhibition) enzyme‐linked immunosorbent assay for HPA‐1a phenotyping of donor platelets was developed. A segment from the donor platelet unit transfer line was sealed to obtain a small aliquot of platelets. These platelets were washed once and added to a predetermined dilution of serum containing alloantibodies to HPA‐1a. Residual anti‐HPA‐1a binding to the glycoprotein IIb/IIIa purified by lectin and high‐performance liquid chromatography and coated on microtiter wells was detected with a conjugated antihuman IgG. A lack of inhibition equivalent to control (no platelets) was used to determine that the platelets were HPA‐1b/b.Results:Of the 557 platelet units tested, 14 (2.5%) were found to be HPA‐1a negative, and they were confirmed to beHPA‐1b/bby DNA genotyping. Two of the 14HPA‐1b/bunits were alsoHPA‐3b/b(approx. 0.35% of the random population). Use of the microtiter format allows 100 to 200 samples to be processed per day.Conclusion:This simple and inexpensive assay is useful for identifying HPA‐1b/b units for platelet‐compatible transfusions or for p

ISSN:0041-1132    

DOI:10.1046/j.1537-2995.1996.36996420758.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY