Transfusion and Apheresis Science

Editorial board/Publication information

2010-02-01

Editorial

Gail Rock — 2010-02-01

In this issue of Transfusion and Apheresis Science we have an outstanding Theme Section edited by Dr. Vassallo from Philadelphia. The theme deals with new developments in platelet storage and transfusion and presents five papers dealing with current aspects of platelet transfusion. Dr. Wagner has dealt with the maintenance of platelet properties at room temperature storage, van der Meer and coworkers address the very important aspect of in vivo recovery and survival of platelets, and Rumjantseva et al. address aspects related to clearance mechanisms of cold platelets. Many will recall that it was previously the practice to store platelets at low temperatures and the assessment of the mechanisms involved with the in vivo clearance of these platelets is important to understand. Bacterial contamination has been a major problem related to current methods of platelet storage which involve temperatures (22°) conducive to bacterial proliferation; these issues are admirably presented by Palavecino and coworkers. Finally, in this series is a paper by Josephson et al. who address the issue of mismatch platelet transfusions and outline strategies to consider. We are delighted to have this assemblage of papers and I’m sure that you, the readers, will find this a very comprehensive overview of the issues related to platelet transfusion.

The first results demonstrating efficiency and safety of a double-column whole blood method of LDL-apheresis

2010-02-01

Abstract: LDL-apheresis is a treatment for familial hypercholesterolemia in addition to diet and drug therapy. In the past, LDL-apheresis techniques consisted in separating plasma from blood and adsorbing plasma LDL-C whereas recent methods remove LDL-C directly from whole blood. The whole blood system developed by Kaneka consists of a single-column (Liposorber DL-75) treatment (SCWB) but a double-column whole blood (DCWB) method has recently been developed (Liposorber DL-50×2).When 1.6 blood volumes (plus 1l) were processed, acute reductions of total cholesterol and LDL-C were 67.9±6% and 80.2±4.5%, respectively. The performances of the DCWB method were compared to other LDL-apheresis methods. Assessed in 10 patients, the DCWB method is more efficient than the SCWB method with higher reduction rates of LDL-C (79.7±4.9 vs. 68.2±5.0% p<0.0001) and apolipoprotein-B (79.5±5.4 vs. 67.4±5.4% p<0.0001). In a sub group of five patients having the highest LDL-C baseline levels, the LDL-C reduction rates obtained by the DCWB method are equivalent to those obtained by the conventional LDL-apheresis method consisting of preliminary plasma separation followed by plasma LDL-C adsorption and used as first line apheresis therapy (80.5±4.5 vs. 79.0±5.9%). The safety of DCWB was demonstrated in 12 patients with only a low frequency of mild and transient adverse effects (4%).In conclusion, the DCWB LDL-apheresis method provides efficient removal of LDL-C, a low level of adverse effects, and a shortened duration of the procedure.

CFSE flow cytometric quantification of lymphocytic proliferation in extracorporeal photopheresis: Use for quality control

2010-02-01

Abstract: Quality control is essential to validate extracorporeal photopheresis (ECP) processes. There is just one protocol based on PHA-induced proliferation. Since it involves the use of radioactive thymidine, we developed another technique using CFSE labeling. We compared the two tests in a paired series including 18 procedures. The thymidine test was valid. Once proliferation was obtained (10 patients out of 13), the CFSE test was in close agreement with it. In particular, two cases of residual proliferation after ECP were simultaneously detected by both techniques. Only the CFSE test allows targeted analysis of lymphocytes, thus identifying a surviving lymphocytic sub-population.

Treatment of symptomatic hyperLp(a)lipidemia with LDL-apheresis vs. usual care

2010-02-01

Abstract: Background/aims: To assess LDL-apheresis efficacy to lower Lp(a) and to compare the effects of Usual Medical Care (UMC) a 12-months study was carried out. The incidence of new coronary artery disease (CAD) events/need of revascularization, was also monitored.Methods: Twenty-one patients with hyperLp(a)lipidemia and angiographically documented CAD were randomly assigned to LDL-apheresis every week, or the UMC.Results: LDL-apheresis group, averaged an Lp(a) reduction of 57.8±9.5% vs. basal values (P<0.001). In the UMC group Lp(a) increased in 1year to 14.7±36.5% (P=0.66). Stepwise multivariate regression analysis for predictors of Lp(a) including: type of treatment, smoking, hypertension, age, age at first cardiovascular event, initial Lp(a), LDL, and BMI values, was performed. Only the type of treatment was co-related (P<0.001): Lp(a) variation (beta)=0.863. The model has R2 adjusted relative risk of 0.725.Conclusion: LDL-apheresis could be the first line treatment of isolated hyperLp(a)lipidemia when CAD is established. New CAD events/cardiac interventions were not observed.

From bloodletting to apheresis in Japan

Toshio Mazda, Paul J. Schmidt — 2010-02-01

Abstract: The ancient therapy of bloodletting that was universal in the West traveled to Japan 500years ago on the trading vessels that carried physicians and barber-surgeons to care for the body and Christian missionaries to care for the soul. Then bloodletting was replaced by blood transfusion in the 19th century, only to return less than 50years ago as apheresis. An understanding of those transitions can be gained from the story of the introduction of Western medicine to Japan and the events that have led to the practice of apheresis there today.

Activation of fibrinolysis by reinfusion of unwashed salvaged blood after total knee arthroplasty

2010-02-01

Abstract: In 19 patients with RA and 20 with OA who underwent autotransfusion with unwashed salvaged blood (USB) after total knee arthroplasty, we performed serial measurement of D-dimer, FgDP, t-PA, and PIC in the plasma and salvaged blood. The PIC level at the completion of salvaged blood transfusion was closely correlated with the volume of USB reinfused in the RA group (p<0.001). The t-PA level of salvaged blood showed a significant positive correlation with the total volume of postoperative drainage in both the RA and OA groups (p<0.05). The increase of total postoperative drainage associated with reinfusion of USB is largely caused by an increase of t-PA in the salvaged blood.

Thrombotic thrombocytopenic purpura as the first manifestation of metastatic adenocarcinoma in a young woman

2010-02-01

Abstract: Thrombotic microangiopathy occurs in 5–10% of patients with mucin-producing disseminated adenocarcinoma. A 28-year-old woman complained of fatigue, bone pain, and weight loss. There were pallor, icterus, and tenderness in the bones on physical examination. Microangiopathic hemolytic anemia, leukoerythroblastic picture, thrombocytopenia, and normal coagulation tests were detected. Thrombotic thrombocytopenic purpura (TTP) was diagnosed and therapeutic plasma exchange was performed on the patient. On day 5 a laparotomy had to be performed because of acute abdomen due to the rupture of a corpus hemorrhagicum follicle of an ovary. Signet ring cell adenocarcinoma stained with cytokeratin 7 and mucicarmine was seen on ovaries and bone marrow, after the pathological examination. The primary site of tumor could not be investigated, because of the patient’s refusal. Although chemotherapy including cis-platinum, infusional 5-flourouracil, and calcium leucovorin were administered in two courses, she died from respiratory failure. In conclusion, malignancy and bone marrow involvement should be considered when associated with leukoerythroblastic picture and TTP.

Theme section: Current topics in platelet storage and transfusion

Ralph R. Vassallo — 2010-02-01

The current theme section extends and expands upon Volume 41.2’s coverage of platelet transfusion therapy. Five contributions from internationally-renowned Transfusion Medicine experts describe cutting-edge issues in platelet storage, evaluation and unit selection for transfusion.

The maintenance of platelet properties during 20–24°C storage after periods of shipment or interrupted agitation

Stephen J. Wagner — 2010-02-01

Abstract: Platelet components are continuously agitated during storage to maintain platelet quality. During shipment, it is not practical to agitate platelets. Numerous studies have investigated the influence of various periods without agitation on the in vitro and in vivo properties of platelet products. This review will examine the outcomes of these studies and consider new developments in platelet storage which might improve platelet quality after interruptions of agitation which occur during platelet shipment.

In vivo tracking of transfused platelets for recovery and survival studies: An appraisal of labeling methods

Pieter F. van der Meer, Bert Tomson, Anneke Brand — 2010-02-01

Abstract: The measurement of recovery and survival of platelets is an important decisive factor when ‘new’ platelet products have been developed. Recovery and survival measurements are mostly performed with radioactive-labeled platelets in healthy volunteers. This approach is required by the FDA for acceptance of platelet products that differ substantially in production or storage conditions from standard methods. However, due to regulatory obstacles, such radiolabeling studies are only carried out in designated institutes. Many countries do not require radioactive labeling studies in volunteers prior to accepting new products, and rather rely on surrogate tests. Also, the European guide to the preparation of blood components does not require this step. This paper reviews alternative, non-radioactive methods, which includes biotinylation of platelets, and discrimination of transfused platelets based on HLA discrepancy. The benefits and disadvantages of these methods will be discussed.

Novel and unexpected clearance mechanisms for cold platelets

Viktoria Rumjantseva, Karin M. Hoffmeister — 2010-02-01

Abstract: Storage at room temperature is limited to 5days because of the risk of bacterial growth and loss of platelet functionality. Platelet refrigeration remains impossible, because once chilled, platelets are rapidly removed from circulation. Chilling platelets (<4h) clusters glycoprotein (GP) Ibα receptors, and β2 integrins on hepatic macrophages recognize clustered βGlcNAc residues leading to rapid clearance of acutely chilled platelets. Prolonged refrigeration increases the exposure of galactose residues such that, unexpectedly, hepatocytes remove platelets using their asialoglycoprotein receptors. Here we review current knowledge of the mechanisms of platelet removal, the existing knowledge of refrigerated platelet function, and methods to preserve platelet concentrates long-term for transfusion.

Bacterial contamination of platelets

Elizabeth L. Palavecino, Roslyn A. Yomtovian, Michael R. Jacobs — 2010-02-01

Abstract: Bacterial contamination of platelet products, both single donor apheresis platelet units and whole blood-derived platelet pools, continues to occur despite preventive measures. While some advances have been made in decreasing the rate of bacterial contamination of platelet units, particularly through diversion methods and early culture, a great deal remains to be done to eliminate the problem. Diversion methods have decreased contamination rates associated with skin commensal organisms. Culture methods are now widely used and many at-issue detection methods have been developed or are undergoing development. This article reviews the current developments and the challenges that remain to minimize and detect bacterial contamination of platelet products.

ABO-mismatched platelet transfusions: Strategies to mitigate patient exposure to naturally occurring hemolytic antibodies

2010-02-01

Abstract: Clinically significant hemolysis is a rare but potentially severe complication of administering an ABO-mismatched platelet transfusion. Platelet products from Group O donors, particularly single donor platelets (SDP) are most commonly implicated in these reactions. This is due to the presence of unusually high titers of anti-A which can be found in the plasma of some Group O donors and the large plasma volume of SDPs. These products can cause significant hemolysis when infused into a Group A or AB recipient. Random donor platelets from Group O donors have also been implicated.In practice, platelets are frequently transfused across ABO barriers though, ideally, in order to prevent or mitigate these reactions, platelet transfusions that are matched for ABO should be administered. However, limited availability of donor platelets as well as an abundance of Group O donors makes this a difficult standard to adhere to since often out-of group products are the only ones available.Methods to improve the safety of Group O products have focused on defining a safe level of isohemagglutinins so that the risk of hemolysis is alleviated when mismatched products are transfused. Determining the critical titer which defines a level above which a mismatched product should not be administered has been challenging. Non-standardized methods of isohemagglutinin titering and varying reports in the literature where products with a wide range of titers have been implicated in acute hemolytic transfusion reactions have made it difficult to determine a cut-off for labeling a product as high titer and thereby restricting its use to O recipients. Standards in the US place the responsibility for designing and implementing policies for the use of mismatched platelet products on each individual hospital transfusion service. Compliance requires only that there be an existing written policy which addresses the transfusion of products containing incompatible ABO antibodies but no specific procedures are required. In sharp contrast, European strategies have defined the low-end titer for which an out-of-group transfusion should not be given to an ABO-incompatible recipient. This testing is performed centrally at the Blood Centers who then make the determination on the status of a “dangerous donor”. The progress in this European strategy may serve the US to stimulate a re-examination of its practices and policies for the advancement of platelet transfusion safety.

SCOTBLOOD 2009: The Quest for Understanding vCJD; Claudia’s Trachea Implantation; Transfusion Triggers; Scottish Histocompatibility and Immunogenetics Network; and Islet Cell Transplantation

Hagop Bessos, Robin Fraser, Jerard Seghatchian — 2010-02-01

Abstract: Scotblood 2009 consisted of a varied combination of leading edge presentations incorporating the past, present and future. Variant CJD was a major feature of the meeting comprising the quest for its understanding and the impact the disease was having on blood donation. The meeting also included the fascinating and groundbreaking story of Claudia’s Trachea transplantation, along with progress in the establishment of the Scottish histocompatibility and immunogenetics network and islet transplantation. The meeting began however with a talk on facilities for the future, outlining major modernization of SNBTS in order to meet future challenges.

Circulating endothelial cells in whole blood donations and the effect of leucodepletion

A. Al-Malki, S. Newton, S.E. Francis, K. El-Ghariani — 2010-02-01

The existence of circulating endothelial cells (CECs) in human peripheral blood was first described in patients with vascular injury and following the novel identification of endothelial progenitor cells, EPCs , special consideration has been directed towards these types of cells and their role in angiogenesis, postnatal vasculogenesis, restoration of the damaged endothelium and malignant growth .

Upcoming events

2010-02-01