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Purpose: Today, haematopoietic stem cell graft from placental blood concerns more than 15 % of allogeneic grafts. An inter-laboratory study of the quality control of defrosted cord blood units has been coordinated by the French society for cell and tissue bioengineering (SFBCT), with the cord blood bank of Bourgogne Franche-Comté and controlled by the French health products safety agency (Afssaps). The aim of this study is to ensure the inter-laboratory reproducibility of the quality controls practised by the banks during defrosting. The cellular outputs were analyzed according to the defrosting techniques, according to the method used in flow cytometry: single-platform (SP) versus double-platform (DP), or the product nature, i.e. in total blood or miniaturized., Methods: Forty-two units of placental blood (USP), which were out of range were provided for defrosting to 14 participating sites. USP were defrosted and controlled according to the procedures of each bank. Once the USP is defrosted, a part of the product was controlled by the site and the other part by Afssaps. Following controls were carried out: numeration of the total nucleated cells (TNC) and of CD34+ cells (made by a SP method in Afssaps) and functional assay., Results: Concerning TNC, the defrosting sites obtained a cellular output of 94 %+/-28 in day 0 compared with an output of 72 %+/-24 in Afssaps showing a rather good stability of the USP transmitted with an average deviation of 23 %+/-22. The freezing process with or without reduction of volume does not affect this variation. Concerning the numeration of CD34+ cells, the average deviation between the participating sites and Afssaps was 29 %+/-23 compared with 21 %+/-16 for the sites using a SP method against 47 %+/-25 for those using a DP method. The CD34+ outputs are equal to 82 % +/- 60 in day 0 for the participating sites against 52 %+/-20 for Afssaps. For the sites using a DP method, it is stressed that this output is particularly high with a rate of 126 %+/-90 (n=15) whereas it is 62 %+/-20 (n=32) for the sites using a SP method., Conclusion: These results underline a good stability of viable CD34+ cells and a greater reliability of the SP methods for the CD34+ cell numeration for these defrosted USP. Lastly, the results of the functional assay regarding the average clonogenicities (equal to 15 %) reinforce the conclusions on the quality of the defrosted products., (Copyright 2010 Elsevier Masson SAS. All rights reserved.)

Photopheresis or extracorporeal photochemotherapy (ECP) is a cellular therapy which combines a leukapheresis followed by ex vivo treatment using psoralen and ultraviolet A irradiation before reinfusion into the patient. Its mechanisms of action remain unclear and selective photodestruction of leukocytes cannot explain the long-lasting immunomodulatory effects. Recent studies demonstrated that ECP down regulates the immune response and induces tolerance through the maturation of dendritic cells and the production of regulatory T cells. Based on these effects, ECP is mainly used for treatment of Sezary syndrome, graft-versus-host disease, organ graft rejection and autoimmune diseases. However, it is still not clear how ECP both activates tumor immunity against cutaneous T-cell lymphoma and induces tolerance in autoreactive disorders. In addition, the use of adjuvant therapies, the long-term effects and various treatment protocols remain to be investigated along with the specific indications.

A cord blood graft is now frequently used in the context of allogeneic hematopoietic transplantation. In 2007, 27% of unrelated allotransplantations performed in France used a cord blood graft. In comparison to other sources of hematopoietic grafts, cord blood has a number of advantages (immediate availability of the graft, possibility of a lesser HLA compatibility between donor and recipient...) and inconveniences (a limited number of stem cells, increased risk of infectious complications...). Recently, the possibility of combining two cord blood grafts has been demonstrated. In 2007, 55% of unrelated cord blood grafts transplantation were performed as such. Results of multicentric studies published as of now, as well as considerable potential associated with cord blood transplantation requires important efforts to increase both the quantity and quality of cord blood grafts made available for transplantation.

Bacterial contamination of blood components remains the highest infectious risk in blood transfusion, the risk is particularly high when it affects platelet concentrates (PC). In France, the residual risk of transfusion reaction due to bacterial contamination of PC has been decreasing slowly since 1994 but for all severity 1 case occurs with about 25,000 distributed PC and one death occurs with 200,000 distributed units. This reduction of the risk may be due to the measures which were implemented during the last 10 years in order to prevent contamination during donation. Improving strategies for reducing the risks of bacterial contamination is one of the priorities of the French National Blood Transfusion Service (l'Etablissement Français du sang - EFS). The main target remains PC. Bacterial detection or pathogens inactivation are now available and are able to reduce (for detection) or prevent (for inactivation) the occurrence of reaction due to bacterial contamination of PC. Up to now, the choice is in favour of bacterial detection. A national study was carried out in seven regional EFS at the end of 2004. It aims at confirming the feasibility of a systematic bacterial screening of PC before their delivery. The first conclusions show that this screening can be implemented with acceptable modifications in term of platelets availability. We can expect in a next future that new pathogens reduction technique and/or new detection systems will be available, certainly more efficient to prevent reaction due to bacterial contamination. Implementation of actual detection methods is probably a temporary solution.

Initial hemovigilance data confirm the incidence and severity of transfusion reactions due to the bacterial contamination of blood components (TRBC). With 18 deaths reported through the French hemovigilance network over the past 5 years, bacterial risks represent one of the major immediate complications of blood components (BC) transfusion. BC contamination may lead to more or less severe TRBC, depending on their origin: bacteria growth, the BC itself or unknown origin. Although the rate of donated blood or BC contamination is known (0.5% and 0.05%, respectively) it is still difficult to assess the actual incidence of TRBC, as it is difficult to identify them and relate them to transfusion. Likewise, better knowledge of bacteria, symptoms and outcome is required to improve prevention methods. Better prevention can reduce BC contamination and proliferation of bacteria at each stage of blood transfusion. Methods to detect BC contamination are still under investigation. Through continuous education of hemovigilance actors in identifying and dealing with TRBC, as well as drawing up procedures to perform inquiries and specific bacterial analyses, case reporting can be further improved in order to achieve more efficient prevention.

Initial hemovigilance data confirm the incidence and severity of transfusion reactions due to the bacterial contamination of blood components (TRBCs). With 18 deaths reported through the French hemovigilance network over the past five years, bacterial risks represent one of the major immediate complications of BC transfusion. BC contamination may lead to more or less severe TRBCs, depending on their origin: bacteria growth, the BC itself or unknown origin. Although the rate of donated blood or BC contamination is known (0.5% and 0.05%, respectively), it is still difficult to assess the actual incidence of TRBCs, as it is difficult to identify and relate them to transfusion. Likewise, a better knowledge of bacteria, symptoms, and outcome is required to improve prevention methods. Better prevention can reduce BC contamination and proliferation of bacteria at each stage of blood transfusion. Methods of detecting BC contamination are still under investigation. Through continuous education of hemovigilance participants in identifying and dealing with TRBCs, as well as drawing up procedures to perform inquiries and specific bacterial analyses, case reporting can be further improved, in order to achieve more efficient prevention.