bluuebunny/crossref_metadata_2025 huggingface dataset:
A multicenter inspection of the swirling phenomenon in platelet concentrates prepared in routine practice
Authors: Bertolini F. , Murphy S. ,   Biomedical Excellence for Safer Transfusion (BEST) Working Party of the International Society of Blood Transfusion
Published: March 2003

BACKGROUND: In a previous multicenter study, the absence of the swirling phenomenon correlated well with platelet disc‐to‐sphere transformation, a morphology feature associated in the past with poor platelet viability.

STUDY DESIGN and METHODS: In 13 centers, 5366 platelet concentrates (PCs) were prepared and stored under routine conditions and evaluated for the presence of swirling. PCs found not to have swirling were evaluated for pH and platelet and white cell counts in parallel with an equal number of PCs with swirling that were studied as controls.

RESULTS: In 13 participating centers, swirling was reported to be absent after 3 and 5 days of storage in 0 to 3.8 percent and in 0 to 18 percent of PCs, respectively. In 94 percent of units with swirling, pH was 6.7 to 7.5; this is a range of values associated with adequate in vivo survival. In 69 percent of PCs without swirling, pH was lower than 6.4 or higher than 7.6; these values are associated with reduced platelet viability. Three‐quarters of the cases in which the absence of swirling was associated with pH values between 6.7 and 7.5 were reported from 2 out of the 13 participating centers.

CONCLUSION: In PCs prepared and stored under routine conditions, the presence of swirling correlated well with pH values associated with adequate platelet in vivo viability. In about 20 percent of PCs without swirling, this was not due to a low or high pH value, and it would be useful to investigate whether this lack of swirling is associated with poor platelet viability. These data support the possibility that the evaluation of swirling by visual inspection might replace invasive and more cumbersome assays currently used for routine PC quality control.
Factors influencing white cell removal from red cell concentrates by filtration
Authors: Ledent E. , Berlin G.
Published: March 2003

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 × 10(6) for 5 mL [p = 0.006] and 14.9 × 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 × 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 × 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 × 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.
Preoperative red cell production in patients undergoing weekly autologous blood donation
Authors: Kasper S. M. , Gerlich W. , Buzello W.
Published: March 2003

BACKGROUND: Modest autologous blood donation programs involving weekly phlebotomy and threshold hematocrits for blood donation higher than 33 percent are frequently used in patients scheduled for elective cardiac surgery. This study was performed to determine the gain in red cells (RBCs) obtained with such a program. STUDY DESIGN AND METHODS: The blood bank and medical records of 225 adult patients (194 men, 31 women; mean age, 57 years [range, 18–77]) who donated blood for autologous use in elective cardiac surgery during a 3‐year period were reviewed. Preoperative RBC production was estimated by the total volume of RBCs donated minus the change in circulating RBC volume between the first donation and the day before surgery. RESULTS: A total of 604 blood units were donated (2.7 units/patient; range, 1–3). The mean volume of RBCs donated was 522 mL (range, 171–732). Mean RBC production (over baseline RBC production) was 351 mL (range, 9–719), or 19 percent (range, 0.5–40) of the circulating RBC volume at baseline. CONCLUSION: A modest autologous blood donation program using three phlebotomies at weekly intervals and a threshold hematocrit for blood donation of 36 percent yields an average of 351 mL (range, 9–719) of RBCs. This is equivalent to 2 units (range, 0.5‐4) of allogeneic packed RBCs at 180 mL per unit.
Removal of anaphylatoxins C3a and C5a and chemokines interleukin 8 and RANTES by polyester white cell‐reduction and plasma filters
Authors: Geiger T.L. , Perrotta P.L. , Davenport R. , Baril L. , Snyder E.L.
Published: March 2003

BACKGROUND: A few bedside polyester white cell (WBC)‐reduction filters have been shown to scavenge C3a anaphylatoxin from stored blood components. One has been shown to remove the chemokines interleukin (IL)‐8 and RANTES, but not the proinflammatory cytokines IL‐1, IL‐6, and tumor necrosis factor alpha. Removal by any filter of the anaphylatoxin C5a or the soluble membrane attack complex (SC5b‐9) has not been studied. Further, the ability of other filters to scavenge these biologic response modifiers (BRM) is not known. Four WBC‐ reduction filters and one plasma filter were studied for their ability to remove IL‐8, RANTES, IL‐1 beta, C3a, C5a, and SC5b‐9. STUDY DESIGN AND METHODS: Plasma was obtained either as freshly thawed fresh‐frozen plasma, fresh‐frozen plasma thawed and stored for 5 days, or platelet‐ poor supernatant. Cell‐poor plasma was obtained and samples were taken before and after filtration through the various filters Levels of IL‐1 beta, IL‐8, RANTES, C3a, and SC5b9 were quantitated by enzyme immunoassay. To evaluate filter scavenging of C5a, an in vitro model was developed to generate high levels of C5a in plasma by activating plasma with zymosan. RESULTS: Levels of C3a, C5a, IL‐8, and RANTES were reduced by filtration through two bedside platelet WBC‐reduction filters, a plasma filter, and a prestorage red cell WBC‐reduction filter, but not following filtration through a prestorage platelet WBC‐ reduction filter. For some BRMs and filters, however, evidence of filter saturation was seen. IL‐1 beta was not removed by any of the filters tested. CONCLUSION: Some, but not all, bedside polyester filters and prestorage polyester filters can remove IL‐8, RANTES, C3a, and C5a from units of plasma or platelets. Improved biomaterial engineering of these and other filters could maximize scavenging of BRMs and potentially diminish the adverse reactions associated with their infusion during transfusion.
Addition of L‐carnitine to additive solution‐suspended red cells stored at 4 degrees C reduces in vitro hemolysis and improves in vivo viability
Authors: Arduini A. , Holme S. , Sweeney J.D. , Dottori S. , Sciarroni A.F. , Calvani M.
Published: March 2003

BACKGROUND: The role of L‐carnitine (LC) as the requisite carrier of long‐chain fatty acids into mitochondria is well established. Human red cells (RBCs), which lack mitochondria, possess a substantial amount of LC and its esters. In addition, carnitine palmitoyl transferase, an enzyme that catalyzes the reversible transfer of the acyl moiety from acyl‐coenzyme A to LC is found in RBCs. It has recently been shown that LC and carnitine palmitoyl transferase play a major role in modulating the pathway for the turnover of membrane phospholipid fatty acids in intact human RBCs, and that LC improved the membrane stability of RBCs subjected to high shear stress. RBC membrane lesions occur during storage at 4 degrees C; this study investigated whether the addition of LC (5 mM) to a standard RBC preservative solution (AS‐3) affected cellular integrity with 42 days' storage. STUDY DESIGN AND METHODS: A paired (n = 10) crossover design was used for RBCs stored in AS‐3 with and without LC. Both in vitro RBC properties reflective of metabolic and membrane integrity and in vivo measures of cell viability (24‐hour percentage of recovery and circulating lifespan) were measured at the end of the storage. In addition, the turnover of membrane phospholipid and long‐chain acylcarnitine fatty acids and the carnitine content of control and LC‐stored RBCs were measured. RESULTS: It was shown that LC was irreversibly taken up by RBCs during storage, with a fourfold increase at 42 days. Furthermore, as found by the use of radiolabeled palmitate, the stored RBCs were capable of generating long‐chain acylcarnitine. The uptake of LC during storage was associated with less hemolysis and higher RBC ATP levels and by a significantly greater in vivo viability for LC‐stored RBCs than for control‐stored RBCs: a mean 24‐hour percentage of recovery of 83.9 +/− 5.0 vs. 80.1 +/− 6.0 percent and a mean lifespan of 96 +/− 11 vs. 86 +/− 14 days, respectively (p < 0.05). CONCLUSION: A beneficial effect of the addition of LC to RBCs stored at 4 degrees C was evident. This effect may be related to both biophysical and metabolic actions on the cell membrane.
Transmission of human immunodeficiency virus through blood transfusion: the use of lookback and traceback approaches to optimize recipient identification in a regional population
Authors: Gill M.J. , Towns D. , Allaire S. , Meyers G.
Published: March 2003

BACKGROUND: The purpose of this study was to define the epidemiologic features of the transmission of human immunodeficiency virus (HIV) by blood transfusion in a region of Canada between 1980 and 1985 and the results of intensive recipient‐identification practices.

STUDY DESIGN AND METHODS: Lookback (notification of all recipients of blood from an HIV‐infected donor) and traceback (identification of the HIV‐infected source donor, after an HIV‐infected recipient of blood cites transfusion as a risk for infection) programs were established linking (with patient consent) a transfusion service and an HIV clinic to identify HIV‐infected donors and the recipients of their blood.

RESULTS: Twenty‐two cases of documented HIV infection and 26 cases of presumed infection were found in local blood recipients. Twenty‐eight recipients have died of causes unrelated to HIV. Twelve recipients have developed AIDS. Six of the seven living recipients have yet to develop an AIDS condition. These 48 infections have been linked to 11 donors who have subsequently tested positive for HIV infection. Six donors were found on subsequent blood donation. Five donors were found by traceback.

CONCLUSION: Forty‐eight recipients of blood from donors who subsequently tested positive for HIV were identified in a low‐ prevalence area. Active lookback and traceback programs linking a transfusion service and an HIV clinic were successful in identifying infected recipients.
Relationship of the time of storage and transfusion reactions to platelet concentrates from buffy coats
Authors: Riccardi D. , Raspollini E. , Rebulla P. , Pappalettera M. , Marangoni F. , Greppi N. , Sirchia G.
Published: March 2003

BACKGROUND: Transfusion reactions to platelet concentrates prepared from buffy coats (BC‐PCs) were reviewed to determine the effect of some variables of BC‐PC preparation and storage: time of BC storage before BC‐PC preparation (1–2 days); time of BC‐PC storage before transfusion (1–5 days); no white cell reduction versus laboratory and bedside BC‐PC white cell reduction.

STUDY DESIGN AND METHODS: A multiple linear logistic regression model was used by which the relative effect of one variable is expressed as the relative risk of transfusion reaction against a baseline level (1‐day storage, no white cell reduction).

RESULTS: During the 14 months of study, a total of 2707 BC‐PC transfusions were given to 192 patients; 37 reactions (1.4%) were reported in 25 patients (13%). The transfusion reactions were febrile, nonhemolytic in 23 cases; allergic in 5; febrile and allergic in 2; and other in 7. The relative risk of transfusion reaction to BC‐PCs prepared from BCs stored for 2 days was 1.98 times that to BC‐PCs prepared from BCs stored for 1 day (p = 0.07). The relative risk of transfusion reaction of 5‐day‐old BC‐PCs was 10.7 times that of 1‐day‐ old BC‐PCs (p = 0.001). The relative risk of transfusion reactions of BC‐PCs white cell‐reduced in the laboratory and at the bedside were 0.65 (p = 0.3) and 1.87 (p = 0.1) times, respectively, that of non‐ white cell‐reduced BC‐PCs.

CONCLUSION: Time of storage seems to be an important variable associated with BC‐PC transfusion reaction.
Risk of iatrogenic human immunodeficiency virus infection through transfusion of blood tested by inappropriately stored or expired rapid antibody assays in a Zambian hospital
Authors: Consten E.C.J. , van der Meer J.T.M. , de Wolf F. , Heij H.A. , Henny P.C. , van Lanschot J.J. B.
Published: March 2003

BACKGROUND: The purpose of this study was to estimate the risk of human immunodeficiency virus (HIV) infection via the transfusion of blood tested by inappropriately stored or expired rapid antibody assays in Zambia. STUDY DESIGN AND METHODS: Surgical patients (n = 370) were tested with antibody assays (HIV‐spot and HIV 1+2) that had expired 3 to 6 months previously. Blood donors (n = 211) were tested by inappropriately stored but non‐expired HIV‐spot assay. Serum samples from both groups were retested with enzyme immunoassays, and the seropositivity of samples was confirmed by immunoblotting. RESULTS: Seroprevalence in surgical patients and blood donors was 19.8 and 11.6 percent, respectively. Sensitivity and specificity of HIV‐spot (expired) were 88.2 and 98.1 percent; those of HIV 1+2 (expired) were 82.1 and 94.7 percent; and those of HIV‐spot (non‐expired) were 91.7 and 98.8 percent, respectively. The risk of HIV infection via the transfusion of blood tested by HIV‐spot (expired), HIV‐spot (nonexpired), or HIV 1+2 (expired) was calculated to be 1.4, 1.0, and 3.2 percent, respectively. CONCLUSION: Manufacturers of the HIV‐spot and HIV 1+2 assays claim sensitivity and specificity of 98.8 and 100 percent and 100 and 99.5 percent, respectively. In this study, sensitivity and specificity were 11 to 18 percent lower. Moreover, in‐ date reagents also performed less well than the manufacturers claimed, but the worst results were with expired or improperly stored reagents. According to the manufacturers of HIV‐spot and HIV 1+2, the risk of HIV infection would be 0.2 and 0 percent, respectively. However, the risk of contracting HIV through transfusion is at least six times higher than expected.
New hepatitis B virus mutant form in a blood donor that is undetectable in several hepatitis B surface antigen screening assays
Authors: Jongerius J.M. , Wester M. , Cuypers H. T.M , van Oostendorp W.R. , Lelie P.N. , van der Poel C.L. , van Leeuwen E.F.
Published: March 2003

BACKGROUND: Envelope mutant forms of hepatitis B virus (HBV), impairing HBV antibody recognition, have been reported with mutations in single or multiple sites of the hepatitis B surface antigen (HBsAg) group‐ specific “a” determinant. Blood donors infected with such an HBsAg mutant form of HBV may escape detection by HBsAg screening assays and therefore may affect the safety of the blood supply. CASE REPORT: A repeat blood donor became HBsAg‐reactive in an enzyme immunoassay. Confirmatory testing yielded negative results for HBsAg in a radioimmunoassay and in four enzyme immunoassays used in blood donor screening. The specificity of the HBsAg reactivity in the first enzyme immunoassay was confirmed by HBsAg neutralization with antibody to HBsAg. Additional HBV confirmatory test results were positive for antibody to hepatitis B core antigen and antibody to hepatitis B e antigen; negative for antibody to HBsAg and for hepatitis B e antigen; and positive for HBV DNA. DNA sequence analysis of the “a” determinant region of HBsAg revealed amino acid substitutions from Q (Gln) to R (Arg) at codon 129 and from M (Met) to T (Thr) at codon 133. CONCLUSION: This case illustrates the presence of HBsAg mutant forms of HBV in a West European blood donor population that were undetected by several HBsAg screening assays. Adaptation of HBsAg screening is indicated to overcome deficiencies in sensitivity in detecting HBsAg mutant forms of HBV. Screening for antibody to hepatitis B core antigen or HBV DNA may also detect blood donors infected with HBsAg mutant forms of HBV
Hemodilution and intravenous perflubron emulsion as an alternative to blood transfusion: effects on tissue oxygenation during profound hemodilution in anesthetized dogs
Authors: Habler O.P. , Kleen M.S. , Hutter J.W. , Podtschaske A.H. , Tiede M. , Kemming G.I. , Welte M.V. , Corso C.O. , Batra S. , Keipert P.E. , Faithfull N.S. , Messmer K.F.W.
Published: March 2003

BACKGROUND: Intravenously administered perfluorocarbon (PFC) emulsions increase oxygen solubility in plasma. PFC might therefore temporarily replace red cells (RBCs) lost during intraoperative hemorrhage. In patients who have undergone hemodilution, the return of autologous blood may be delayed by the administration of PFC, and autologous RBCs may be saved for transfusion after surgical bleeding is stopped and PFC is cleared by the reticuloendothelial system. STUDY DESIGN AND METHODS: In 22 anesthetized, hemodiluted dogs (hemoglobin [Hb] 7 g/dL) breathing 100‐percent O2, an intraoperative volume‐compensated blood loss was simulated. The efficacy of three therapeutic regimens in maintaining tissue oxygenation was compared: 1) RBC group (n = 7): maintenance of a Hb > 7 g per dL by transfusion of autologous RBCs; 2) PFC group (n = 7): bolus application of a second‐generation PFC emulsion (60% wt/vol perflubron) and further acute normovolemic hemodilution (ANH) to a Hb of 3 g per dL; and 3) control group (n = 7): further ANH alone to a Hb of 3 g per dL. Systemic and myocardial oxygenation status and tissue oxygenation were assessed. RESULTS: Autologous RBCs transfused to maintain a Hb of 7 g per dL preserved hemodynamics and tissue oxygenation during blood loss. In the PFC and control groups, heart rate and cardiac index increased significantly in response to further ANH. Tissue oxygenation was not different in the PFC and the RBC groups. Direct comparison of the PFC and control groups revealed better tissue oxygenation in the PFC group, as reflected by significantly higher mixed venous, coronary venous, and local tissue pO2 on liver and skeletal muscle. CONCLUSION: Bolus intravenous administration of 60‐ percent (wt/vol) perflubron emulsion and further hemodilution from a Hb of 7 g per dL to one of 3 g per dL were as effective as autologous RBC transfusion in maintaining tissue oxygenation during volume‐compensated blood loss designed to mimic surgical bleeding.
An enzyme‐linked immunosorbent assay for the quantitation of IgG anti‐D and IgG subclasses in the sera of alloimmunized patients
Authors: Lambin P. , Ahaded A. , Debbia M. , Lauroua P. , Rouger P.
Published: March 2003

BACKGROUND: IgG subclass composition of maternal alloantibodies to the D antigen seems to play a role in the severity of hemolytic disease of the newborn. The subclassing of IgG anti‐D is usually performed by hemagglutination techniques, but the results are not quantitative and sometimes are difficult to interpret. Thus, there is a need for quantitative methods. STUDY DESIGN AND METHODS: The aim of this study was to develop an enzyme‐linked immunosorbent assay (ELISA) for the quantitation of specific IgG anti‐D and IgG subclasses in the sera of alloimmunized patients. Group O R1R2 red cells were sensitized with anti‐D. Red cell membranes were solubilized with nonionic detergent. IgG and IgG subclasses were measured by a sensitive and reproducible immunocapture ELISA. A serum calibrated for its IgG subclass content was used as a reference, and the anti‐D preparation 68/419 was used as an internal control. Optimal conditions for the detection of IgG anti‐D and IgG subclasses by ELISA were studied. The absolute concentration and the proportions of IgG subclasses were determined in the sera of 14 pregnant women. RESULTS: A close parallelism was observed between dilutions of the IgG reference serum and the IgG anti‐D solubilized from sensitized RBCs. The sum of IgG anti‐D subclass concentrations, determined by the ELISA, correlated well with other quantitative methods. CONCLUSION: The method described is sensitive and can be used routinely for the quantitative determination of specific IgG anti‐D and IgG subclasses in sera.
Thrombotic thrombocytopenic purpura that is refractory to therapeutic plasma exchange in two patients with occult infection
Authors: Creager A.J. , Brecher M. E. , Bandarenko N.
Published: March 2003

BACKGROUND: The etiology of thrombotic thrombocytopenic purpura (TTP) remains undetermined. TTP has been associated with a number of secondary causes including infections, drugs, menses, pregnancy, autoimmune diseases, and bone marrow transplantation. Regardless of the inciting factors, it is widely accepted that endothelial injury and platelet aggregation are integral components. The morbidity and mortality have been significantly reduced with the use of plasmapheresis. However, refractory forms of TTP remain a clinical management challenge. Refractory TTP has not previously been associated with occult bacterial infection.

CASE REPORT: Two patients had classic TTP that was refractory to daily plasma exchange with fresh‐frozen plasma. Multiple attempts over a period of months to wean these patients off plasma exchange resulted in exacerbations of disease activity, as indicated by increased schistocytosis, decreased hematocrit, increased serum lactate dehydrogenase, and decreased platelet counts. Both patients were empirically treated for infections during hospitalization, although microbial cultures failed to isolate an organism. Discontinuation of antimicrobial therapy on multiple occasions in one patient was associated with recurrence of disease. In the other patient, dental extraction with drainage of an occult periodontal abscess resulted in sustained remission of disease.

CONCLUSION: Occult bacterial infection may play a role in triggering and sustaining TTP that is refractory to conventional treatment. A careful search for such an infection and appropriate antimicrobial therapy should be considered in the management of these patients.
The transfusion needs of an autologous bonemarrow transplant patient with IgA deficiency
Authors: Meena‐Leist C.E. , Fleming D.R. , Heye M. , Herzig R.H.
Published: March 2003

BACKGROUND: Transfusion management of the patient who is undergoing a marrow or peripheral blood stem and progenitor cell transplantation is often challenging. The situation is further complicated when the patient is IgA deficient with circulating anti‐IgA.

CASE REPORT: This report describes an approach to transfusion therapy primarily using red cells washed by automated techniques and cryopreserved autologous plateletpheresis components. Additional platelet support was provided with manually washed allogeneic plateletpheresis components. Autologous fresh‐frozen plasma was collected concurrently, and IgA‐deficient allogeneic units were ordered and kept in storage, but they were not needed during transplantation. The patient experienced no transfusion sequelae as a result of the IgA deficiency.

CONCLUSION: With this approach, the transfusion needs of an IgA‐deficient patient were adequately met during bone marrow transplantation.
Storage of whole blood before separation: the effect of temperature on red cell 2,3 DPG and the accumulation of  lactate
Authors: Högman C.F. , Knutson F. , Lööf H.
Published: March 2003

BACKGROUND: Although whole blood intended for component preparation is commonly left to cool at ambient temperature, knowledge is insufficient as to the effects this may have on red cell quality, in particular after a prolonged hold.

STUDY DESIGN AND METHODS: Whole blood collected in ACD‐A (7% wt/wt) and CPD (12% wt/wt) was incubated at 4, 10, 15, 20, 25, and 30°C for 24 hours. Blood gases, pH, bicarbonate, glucose, lactate, and red cell 2,3 DPG were investigated.

RESULTS: When the blood was stored at 30°C, the 2,3 DPG concentration decreased within 4 hours from 858 ± 106 to 316 ± 172 mmol per mol of hemoglobin (a 63% decrease); 99 percent was lost within 18 hours. At 25°C, 46 percent was lost within 4 hours and 94 percent within 18 hours; at 20°C, the decrease at 18 hours was 62 percent and that at 15°C was 24 percent. No loss of 2,3 DPG was observed at 4°C and 10°C storage. No difference was attributable to the anticoagulant used. After 24 hours, the lactate concentration at 15°C was 2.9 times the original, that at 20°C was 3.8 times the original, that at 25°C was 7.0 times, and that at 30°C was 9.2 times.

CONCLUSIONS: With current anticoagulants, storage of whole blood at temperatures of 25 to 30°C before separation causes a great and rapid loss of 2,3 DPG and an accumulation of acid metabolites. In a hold of blood for >4 hours, rapid cooling is desirable to avoid initial loss of 2,3 DPG.
Comparative evaluation of 14 immunoassays for detection of antibodies to the human T‐lymphotropic virus types I and II using panels of sera from Sweden and West Africa
Authors: Andersson S. , Thorstensson R. , Ramirez K. Godoy , Krook A. , Von Sydow M. , Dias F. , Biberfeld G.
Published: March 2003

BACKGROUND: A new generation of assays for the detection of human T‐lymphotropic virus types I and II (HTLV‐I/II) antibodies has been released. These assays incorporate HTLV‐I‐ and HTLV‐II‐specific antigens, and some are based on new assay principles. Comparative evaluation data that include these new as well as previous assays are limited.

STUDY DESIGN AND METHODS: Fourteen HTLV antibody assays were evaluated by using well‐characterized panels of sera from Guinea‐Bissau, West Africa, and Sweden. The sera included 127 HTLV‐I‐positive and 62 HTLV‐II‐positive specimens, as well as 919 consecutive negative samples.

RESULTS: The sensitivity for HTLV‐I was 100 percent for all assays, except one, which repeatedly missed one sample. The sensitivity for HTLV‐II varied between 86 percent and 100 percent. In general, new‐generation assays incorporating HTLV‐II‐specific antigens, and some of which are based on new assay principles, had a higher sensitivity for HTLV‐II than previous assays, which mainly are based on HTLV‐I antigens. The specificity was generally higher for new assays than for the previous versions. Testing of Swedish blood donor sera gave higher specificities (94‐100%) than did that of African specimens (90‐99.7%). Most assays had low delta values (DVs), although there was a tendency toward increased DVs for the new generation of assays. Only two of the new generation of assays came close to a combination of high sensitivity for both HTLV‐I and HTLV‐II, high specificity, positive and negative predictive values, and high DVs.

CONCLUSION: The sensitivity for HTLV‐I was generally high and appears to have improved for HTLV‐II with the introduction of a new generation of assays incorporating HTLV‐II‐specific antigens. However, some assays still give false‐negative results on HTLV‐II‐positive specimens. The specificities and the DVs were generally higher for the new assays than for the previous versions.
Reduction of blood loss by infusion of human platelets in a rabbit kidney injury model
Authors: Krishnamurti C. , Maglasang P. , Rothwell S.W.
Published: March 2003

BACKGROUND: As a first step toward testing the efficacy of stored platelets or platelet substitutes in vivo, a kidney injury model was developed to assess the hemostatic properties of human platelets in normal and thrombocytopenic rabbits.

STUDY DESIGN AND METHODS: New Zealand white rabbits were made thrombocytopenic by two consecutive injections of busulfan. Two weeks later, human platelets were transfused to animals whose reticuloendothelial systems were inhibited by the administration of ethyl palmitate. The left kidney was exposed and a slice excised from the anterior pole. The blood was contained in a parafilm boat and absorbed by preweighed gauze to assess blood loss. The percentage of human platelets transfused to the rabbit was determined by flow cytometry on blood collected from the cut site using anti‐CD42a (marker for human platelets). The degree of activation of the human platelets was determined using anti‐CD62a (marker specific for human p‐selectin).

RESULTS: Blood loss was similar in normal animals treated with saline alone (35.4 ± 5.8 g; n = 4); ethyl palmitate and saline (42.5 ± 5.7 g; n = 6, p = 0.4); or ethyl palmitate and fresh human platelets (45.7 ± 7.9 g; n = 6, p = 0.3). Bleeding in thrombocytopenic rabbits infused with saline was increased (75.6 ± 3.9 g; n = 7) as compared with nonthrombocytopenic animals. A significant reduction in blood loss was noted in thrombocytopenic rabbits given fresh human platelets (51.6 ± 4.5 g; n = 6, p = 0.0023). Transfusion of human platelets to rabbits did not cause activation of the platelets. Furthermore, transfusion of thrombin‐activated platelets (60‐98% activated) to thrombocytopenic rabbits reduced blood loss (54 ± 7.3 g; n = 7) to the same extent as fresh platelets.

CONCLUSIONS: This is the first report describing a kidney injury model developed to assess the efficacy of fresh and activated human platelets in reducing blood loss in thrombocytopenic rabbits. This model could monitor the efficacy of human platelets prepared by various preservation protocols in suppressing bleeding in rabbits.
A prospective, randomized, sequential, crossover trial of large‐volume versus normal‐volume leukapheresis procedures: effect on progenitor cells and engraftment
Authors: Humpe A. , Riggert J. , Munzel U. , Repas‐Humpe L.M. , Vehmeyer K. , Brunner E. , Wörmann B. , Köhler M.
Published: March 2003

BACKGROUND: The influence of leukapheresis size on the number of harvested peripheral blood progenitor cells is still unclear. A prospective randomized crossover trial was thus performed, to evaluate the effect of large‐volume leukapheresis (LVL) versus normal‐volume leukapheresis (NVL) on progenitor cells and engraftment in 26 patients with breast cancer and 15 patients with non‐Hodgkin–s lymphoma who were eligible for peripheral blood progenitor cell transplantation.

STUDY DESIGN AND METHODS: Patients were randomly assigned to undergo either LVL on Day 1 and on Day 2 or vice versa. The number of progenitor cells was evaluated in the harvest and before and after leukapheresis in the peripheral blood.

RESULTS: The number of harvested CD34+ cells (4.8 × 106 vs. 3.4 × 106/kg body weight, p<0.001) and colony‐forming units–granulocyte‐macrophage (3.1 × 105 vs. 2.4 × 105/kg body weight, p = 0.0026) was significantly higher for LVL procedures than for NVL procedures. The median extraction efficacy, defined as the difference between the yield in the harvest and the decrease in the total number of CD34+ cells in peripheral blood during leukapheresis, was significantly (p<0.0001) higher for LVL than for NVL (2.6 × 108 and 8 × 107, respectively). In patients with breast cancer, the median amount of CD34+ cells in the harvest and the median extraction efficacy were higher for LVL than for NVL (p<0.0001). This was not found for patients with non‐Hodgkin's lymphoma.

CONCLUSION: LVL results in a higher yield of CD34+ cells and colony‐forming units–granulocyte‐macrophage than NVL, but only in patients with breast cancer and with high numbers of CD34+ cells in the peripheral blood before leukapheresis.
Febrile and allergic transfusion reactions after the transfusion of white cell‐poor platelet preparations
Authors: Klüter H. , Bubel S. , Kirchner H. , Wilhelm D.
Published: March 2003

BACKGROUND: Nonhemolytic transfusion reactions (NHTRs) frequently occur after platelet transfusions. White cell (WBC)‐derived inflammatory cytokines can cause these reactions, but they are rarely found in WBC‐poor platelet preparations. Transfusion reactions were investigated with regard to the residual WBC content in the stored platelet concentrate in two consecutive study periods.

STUDY DESIGN AND METHODS: In the first study period, platelet concentrates were WBC‐reduced by bedside filtration. In the second period, all platelet concentrates were filtered before storage. Recipients who experienced transfusion reactions were examined with regard to their main clinical symptoms during and after transfusion. In the supernatant of the involved platelet concentrates, concentrations of interleukin (IL)‐1β, IL‐6, IL‐8, tumor necrosis factor (TNF)α, macrophage inflammatory protein 1α, and RANTES were analyzed.

RESULTS: The incidence of transfusion reactions remained steady when the transfusion regimen was changed from bedside filtration to prestorage WBC filtration (1.63% and 1.56%; p = 0.84). In both periods, NHTRs were predominantly of allergic origin. Inflammatory mediators IL‐1β, IL‐6, IL‐8, and TNFα were detectable in only a minority of platelet components involved in NHTRs. Platelet concentrates involved in allergic reactions contained high concentrations of RANTES (668 ± 223 ng/mL).

CONCLUSIONS: Prestorage WBC filtration did not reduce the incidence of these reactions, and inflammatory cytokines were of minor relevance. The proinflammatory platelet‐derived chemokine RANTES, which accumulates even in WBC‐reduced platelet concentrates, was associated with allergic transfusion reactions. Platelet‐derived mediators may be a key to understanding NHTRs.
High platelet contamination in progenitor cell concentrates results in significantly lower CD34+ yield after immunoselection
Authors: Reiser M. , Draube A. , Scheid C. , Fuchs M. , Josting A. , Diehl V. , Söhngen D.
Published: March 2003

BACKGROUND: Selection of CD34+ cells by specific immunoselection leads to a significant loss of those cells. The factors influencing the yield and purity are not well identified. The results of CD34+ selection from peripheral blood progenitor cells (PBPCs) with high and low platelet contamination that are harvested with two different cell separators are reported.

STUDY DESIGN AND METHODS: A progenitor cell concentrator (Ceprate SC, CellPro) was used to select CD34+ cells from 41 PBPC concentrates from 23 consecutive patients with relapsed non‐Hodgkin's lymphoma (n = 3), breast cancer (n = 17), and multiple myeloma (n = 3). PBPC collection was performed by using two cell separators (CS3000 Plus, Fenwal: Group A, n = 11; and Spectra, COBE: Group B, n = 9). To reduce platelet contamination in the Spectra PBPC concentrates, an additional low‐speed centrifugation was performed before CD34+ cell selection (Group C, n = 3). Leukapheresis components were stored overnight at 4°C and combined with the next day's collection before the CD34+ selection procedure in 19 patients.

RESULTS: A median of 1.5 leukapheresis procedures per patient were performed. Pooled PBPC concentrates showed no statistical difference in median numbers of white cells and CD34+ cells in Groups A and B: 3.2 (0.8‐9.2) versus 4.4 (1.6‐8.3) × 1010 white cells per kg and 15.0 (4.7‐24.0) versus 12.0 (5.6‐34.0) × 106 CD34+ cells per kg. Platelet contamination was significantly higher in Group B: 0.67 (0.15‐2.4) versus 2.3 (0.5‐7.1) × 1011 (p = 0.0273). After the selection process, there was a significantly greater loss of CD34+ cells in Group B than in Group A: 39.1 versus 63.2 percent (p = 0.0070), with a median purity of 78.0 percent versus 81.0 percent. An additional low‐speed centrifugation before CD34+ cell selection seemed to reduce CD34+ cell loss in Group C with 16.9, 31.9, and 37.5 percent, respectively.

CONCLUSION: CD34+ cell selection from PBPC concentrates resulted in an increased loss of CD34+ cells in concentrates with a higher platelet content. To improve CD34+ yield, PBPC concentrates with an initially low platelet contamination should be used, or additional low‐speed centrifugation should be performed.
A fully automated blood typing system forhospital transfusion services
Authors: Sandler S.G. , Langeberg A. , Avery N. , Mintz P.D. ,   for the ABS2000 Study Group
Published: March 2003

BACKGROUND: The results of routine blood bank testing by a fully automated blood typing system (ABS2000) were compared with those obtained by standard manual methods in six hospital transfusion services.

STUDY DESIGN AND METHODS: The ABS2000 system uses microtiter plates for determining ABO and D types, solid‐phase red cell adherence (SPRCA) assays for antibody detection, and modified SPRCA plates for IgG crossmatches. The transfusion services used their standard manual test tube methods.

RESULTS: Of 3779 donors' samples tested for ABO types (red cell typings only), 3.0 percent could not be interpreted by the ABS2000 system's neural network, because of clots, hemolysis, or lipemic samples. The results for ABO types were concordant for 99.8 percent of the remaining samples. Of 3779 donors' samples tested for D types, the results were concordant for 98.7 percent. Of 7580 patients' samples tested for ABO types (red cell and plasma typings), 5.8 percent could not be interpreted by the ABS2000 system. There was 100‐percent concordance of ABO typing results for the remaining 7140 samples. There was 99.7‐percent concordance of results for patients' D types. The results of 96.7 percent of antibody detection tests and 98.8 percent of crossmatches were concordant. Neither method failed to detect a serologically incompatible crossmatch that was associated with a specific, clinically significant alloantibody. The ABS2000 system performed 45 confirmatory donor ABO and D types in 115 minutes, 22 antibody detection tests in 116 minutes, 16 patients' ABO/D types in 149 minutes, and 40 crossmatches in 140 minutes.

CONCLUSION: The ABS2000 blood typing system automates routine blood bank tests with accuracy comparable to that of hospital transfusion services' standard manual methods.
Prevalence of the newly described human circovirus, TTV, in United States blood donors
Authors: Handa A. , Dickstein B. , Young N.S. , Brown K.E.
Published: March 2003

BACKGROUND: A novel nonenveloped single‐stranded circular DNA virus (TTV) was recently identified. The prevalence of TTV in blood donors in the United States is, however, still unclear.

STUDY DESIGN AND METHODS: Viral DNA was detected in US blood donors from five cities by using two sets of TTV primers: NG059/NG061/NG063 primers, which amplified the conserved region of strains 1 and 2, and T801/T935 primers, which amplified the 5' end region of the TTV sequence. A TTV antibody assay system was based on the detection of the truncated open reading frame (ORF)‐1 (amino acids 1‐411) from type 1b. The truncated ORF‐1 was expressed as a fusion protein in Escherichia coli, and the fusion protein was used as the antigen in the antibody assay system.

RESULTS: Viremia was detected in 21 (8.4%) of 250 donors by use of NG059/NG061/NG063 primers and 104 (41.6%) of 250 by use of T801/T935 primers. There was little correlation among the assays, which suggests the preferential detection of different strains with the different primers. TTV antibody was detected in 38 of 100 donors: 32 (84%) of 38 with concurrent TTV viremia and 6 (16%) of 38 without TTV viremia. TTV viremia and/or TTV antibody‐positive samples were detected in 52 (52%) of 100 of US blood donors.

CONCLUSION: Evidence of infection or exposure to TTV appears to be common among blood donors in United States.
Functional characteristics of neutrophils collected and stored after administration of G–CSF
Authors: Leavey P.J. , Thurman G. , Ambruso D.R.
Published: March 2003

BACKGROUND: Granulocyte transfusion may be used in neutropenic patients with severe bacterial or fungal infections that are unresponsive to antibiotic therapy. However, the inability to store granulocyte concentrates limits their clinical usefulness.

STUDY DESIGN AND METHODS: Neutrophil chemotaxis and NADPH oxidase activity and the integrity of the neutrophil NADPH oxidase system were examined after apheresis collection and during storage to 48 hours. Neutrophils were mobilized in vivo by G–CSF, collected by apheresis techniques, and stored in apheresis bags in the presence and absence of additional G–CSF. For all experiments, cells were further purified by standard techniques of dextran sedimentation and hypotonic RBC lysis.

RESULTS: Neutrophil chemotaxis was preserved to 24 hours of storage but was not affected by the G–CSF added to storage units. The NADPH oxidase system was also preserved as a functioning complex, and both cytosolic proteins and membrane‐associated proteins were normal to 48 hours. However, there were divergent responses by intact cells to activating stimuli and reduced oxidase activity in the cell‐free system. G–CSF did not appear to significantly affect NADPH oxidase activity or NADPH oxidase system integrity during storage.

CONCLUSION: Neutrophils collected after the administration of G–CSF retained functional and biochemical characteristics for at least 24 hours of storage, which suggests additional effects of G–CSF mobilization beyond enhancing PMN yields and the possibility of storage of these components after collection.
Absence of evidence of infection with divergent primate T‐lymphotropic viruses in United States blood donors who have seroindeterminate HTLV test results
Authors: Busch M.P. , Switzer W.M. , Murphy E.L. , Thomson R. , Heneine W. ,   for the Retrovirus Epidemiology Donor Study
Published: March 2003

BACKGROUND: Recent identification of divergent simian or primate T‐lymphotropic viruses (STLVs; PTLVs) in bonobos (formerly called pygmy chimpanzees; Pan paniscus; viruses: STLVpan‐p and STLVpp1664) and a baboon (Papio hamadryas; viruses: STLVph969 or PTLV‐L) have raised the possibility of human infection with these viruses. Divergent PTLV‐infected primate sera show p24 bands on HTLV‐I Western blots (WBs). It was investigated whether infection by divergent PTLV‐like viruses could explain a subset of United States blood donors who reacted on HTLV‐I EIAs and had indeterminate HTLV‐I WBs with p24 bands.

STUDY DESIGN AND METHODS: Epidemiologic characteristics of 1889 donors with HTLV‐I‐indeterminate WBs were compared to those of donors with confirmed retrovirus infections (393 with HIV, 201 with HTLV‐I, 513 with HTLV‐II) and 1.6 million donors with nonreactive screening tests. To directly probe for infection with divergent PTLVs, 2 HTLV‐I‐indeterminate donors born in Africa and 269 representative non‐African‐born donors with p24 bands on HTLV‐I WBs (previously shown to be negative for HTLV‐I and ‐II DNA by PCR) were selected for PTLV PCR analysis. DNA from peripheral blood MNC samples was tested for a proviral tax sequence by PCR using generic primers that amplify HTLV‐I, HTLV‐II, and the divergent PTLVs. Amplified tax sequences were detected by Southern blot hybridization to a 32P‐labeled generic PTLV probe. PCR‐positive samples could then be typed by hybridization with virus‐specific internal probes that differentiate HTLV‐I, HTLV‐II, PTLV‐L, and STLVpan‐p.

RESULTS: In the epidemiologic analysis, HTLV‐indeterminate status was independently associated with age of at least 25 years (OR = 2.19; 95% CI, 1.93‐2.49), black (OR = 3.27; 95% CI, 2.90‐3.67) or Hispanic (OR = 1.82; 95% CI, 1.52‐2.16) race or ethnicity, and donation at one blood center (Baltimore) (OR = 1.30; 95% CI, 1.11‐1.53). None of the 271 HTLV‐I WB‐indeterminate samples tested positive by generic PTLV PCR analysis.

CONCLUSION: Although the epidemiologic data suggest the possibility of undiagnosed HTLV‐I, HTLV‐II, or a cross‐reactive virus such as PTLV among older, black, and Hispanic blood donors, the PCR data do not support the presence of divergent PTLV infection among US blood donors with HTLV‐I‐indeterminate results.¤
Mother‐to‐infant transmission of GB virus type C/HGV
Authors: Ohto H. , Ujiie N. , Sato A. , Okamoto H. , Mayumi M. ,   for the Vertical Transmission of Hepatitis Viruses Collaborative Study Group
Published: March 2003

BACKGROUND: The potentially hepatotropic flavivirus‐like virus, GB virus type C (GBV‐C)/HGV, has been detected in a few patients with acute and chronic hepatitis and in a certain proportion of blood donors and recipients of blood or blood components.

STUDY DESIGN AND METHODS: Sera from 2979 pregnant Japanese women were examined for the presence of GBV‐C/HGV RNA by nested RT‐PCR. Mothers who were positive for viral RNA and their 34 infants were followed and tested for infection.

RESULTS: Of the 2979 women, 32 (1.1%) were positive for GBV‐C/HGV RNA. Twenty‐six (76.5%) of 34 babies born to these women were positive for the virus when first tested. A significantly higher titer of viral RNA was observed in mothers whose infants were infected than in those whose infants were uninfected (mean ± SD, 106.3 ± 0.9 vs. 104.6 ± 0.9/mL; p<0.001). Twenty‐three (96%) of 24 babies born to mothers whose serum viral titers were 106 mL or more were infected with the virus. Infants delivered by elective caesarean section had a lower risk (OR, 0.13; 95% CI, 0.02‐0.82) than those delivered vaginally or by emergency caesarean section. No other risk factors for mother‐to‐infant transmission were confirmed.

CONCLUSIONS: GBV‐C/HGV is frequently transmitted from mothers to infants in the general population. The most critical factor is the titer of viral RNA in the maternal serum. By the use of elective caesarean section in women with high titers of viral RNA, vertical transmission of the virus may be lessened.