Tips and tricks for flow cytometry-based analysis and counting of microparticles.

Submicron-sized extra-cellular vesicles generated by budding from the external cell membranes, microparticles (MPs) are important actors in transfusion as well as in other medical specialties. After briefly positioning their role in the characterization of labile blood products, this technically oriented chapter aims to review practical points that need to be considered when trying to use flow cytometry for the analysis, characterization and absolute counting of MP subsets. Subjects of active discussions relative to instrumentation will include the choice of the trigger parameter, possible standardization approaches requiring instrument quality-control, origin and control of non-specific background and of coincidence artifacts, choice of the type of electronic signals, optimal sheath fluid and sample speed. Questions related to reagents will cover target antigens and receptors, multi-color reagents, negative controls, enumeration of MPs and limiting artifacts due to unexpected (micro-) coagulation of plasma samples. Newly detected problems are generating innovative solutions and flow cytometry will continue to remain the technology of choice for the analysis of MPs, in the domain of transfusion as well as in many diverse specialties.

Biomarker analysis of stored blood products: emphasis on pre-analytical issues.

Millions of blood products are transfused every year; many lives are thus directly concerned by transfusion. The three main labile blood products used in transfusion are erythrocyte concentrates, platelet concentrates and fresh frozen plasma. Each of these products has to be stored according to its particular components. However, during storage, modifications or degradation of those components may occur, and are known as storage lesions. Thus, biomarker discovery of in vivo blood aging as well as in vitro labile blood products storage lesions is of high interest for the transfusion medicine community. Pre-analytical issues are of major importance in analyzing the various blood products during storage conditions as well as according to various protocols that are currently used in blood banks for their preparations. This paper will review key elements that have to be taken into account in the context of proteomic-based biomarker discovery applied to blood banking.

[Recipients adverse reactions in the Ibn Sina Hospital of Rabat: State 1999-2013]. / Effets indésirables receveurs à l'hôpital Ibn Sina de Rabat : bilan 1999­2013.

PURPOSE OF STUDY: The declaration of the recipients adverse reactions (RAR) is one of the field haemovigilance activities. It provides an evaluation of transfusion side effects and thus prevents their appearance. The aim of this study is to analyze, over 14 years, the RAR supports reported in Rabat Ibn Sina hospital. PATIENTS AND METHODS: All of the RAR supports sending to the blood transfusion service were analyzed. The data collected from these supports are: clinical characteristics of the patient, type of incident observed and type of labile blood products (LBP) transfused. RESULTS: A total of 353 RAR were declared with a mean cumulative incidence of 1.7/1000 LBP delivered. Febrile non-hemolytic transfusion reactions represent 72.8% of the RAR declared. The RAR were classified as grade 1 in 87.1% of cases and were secondary to a transfusion of the red cell concentrates in 81.9%. ABO incompatibility was found in four cases (0.02/1000 LBP delivered). CONCLUSION: The number of RAR reported by Rabat Ibn Sina hospital remains underestimated. Management and traceability RAR and rigorous investigation, under the responsibility of the corresponding haemovigilance contribute to the improvement of transfusion safety.

[Computer assisted prescription of labile blood products: What are we expecting?] / L'apport de la prescription assistée par ordinateur des produits sanguins labiles.

Computer assisted prescription of labile blood products is just at its beginning. Current programs already allow embedding automatically such data as patient's and prescribers' identification or ward details to produce readable prescriptions, also complying with part of Good Practice guidelines. Now prescriptions can also be sent electronically to the Etablissement Francais du Sang, the French blood products services. Usually they are computer programs specialised in transfusion and interfaced with the main patient's file software. Hardly ever the main software is able to manage transfusion itself. Next step would consist in performing checks, calculations or displaying warning or help messages based on academic or local medical recommendations or even tailored to pre-defined individual requirements. But these call for direct access to patient's data such as diagnosis or tests results, that must be accurately classified and coded before use. The main software could provide such functionalities: but actually that would be infrequent and difficult to transpose from one hospital to the other, regarding to the diversity of main software and their settings. Another solution would be to enhance the very few transfusion specialised programs in order to assist prescribers. Data could be prepared and sent by the main software according to a standardised format each time a prescription is to be entered. This standardised format should be independent from software in order to ensure interoperability, whatever the main and specialised programs. The content and format of this data exchange has to be defined, but this would allow hundreds of hospitals to provide a comprehensive tool for prescription of labile blood products, regardless of their main patient's file software.

[Blood representations associated to chronic transfused patients: Symbolic interpretations and ethical perspectives]. / Lectures des représentations du sang chez les receveurs chroniques de produits sanguins labiles : interprétations symboliques et perspectives éthiques.

Since the beginning of the 20th century, major technological developments have been made in blood transfusion. Although numerous sociological studies have been conducted on donors, few have highlighted transfused patients, and in this case, the attention has almost exclusively been focused on transfusion risks in patients. Conversely, blood representations associated with the chronically transfused patients have not really been explored in the literature. Based on interviews conducted among chronically transfused patients (patients with hemoglobinopathy, malignant hemopathy or cancer), this present study enables to understand their needs and their expectations through their symbolic representations and their interpretations of blood transfusion, raising tensions as well ethical perspectives.

[New viral risks in blood transfusion by 2016]. / Nouveaux risques viraux en transfusion sanguine à l'horizon 2016.

Viral safety remains a major concern in transfusion of blood products. Over years, the control measures applied to blood products were made more and more sophisticated; however, the number of infectious agents, and notably of viruses, that can be transmitted by transfusion is increasing continuously. The aim of this review paper is to actualize that published in the same journal by the same authors in 2011 with more details on some of actual vs virtual viral threats that were identified recently in the field of blood transfusion. The main subjects that are covered successively concern the transmission via transfusion of hepatitis E virus, the frequency of transfusion transmitted arboviruses, transfusion at the time of the Ebola epidemics in West Africa, the debated role of Marseillevirus (giant viruses infecting amoebae and suspected to infect human blood latently), and, finally, the recent report of the identification in blood donors of a new member of the Flaviviridae family. The addition of these new viral risks to those already identified-partially controlled or not-pleads for the urgent need to move forward to considering inactivation of infectious agents in blood products.