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Saint-Sauveur-en-Rue, France

Rinaudo-Gaujous M.,Laboratoire dImmunologie | Talagrand E.,Laboratoire dHematologie | Verhoeven P.O.,Laboratoire Of Bacteriologie | Garraud O.,Jean Monnet University | Flourie F.,EFS Auvergne Loire
Annales de Biologie Clinique | Year: 2013

Pediatric hemolytic uremic syndrome (HUS) is a rare complication of infections usually caused by Escherichia coli; Streptococcus pneumoniae may be a causative agent in 5% of cases and is often more serious in terms of morbidity and mortality. We report a case of pediatric HUS following an infection by a serotype of S. pneumoniae not included in the vaccine administered to the child. Bacterial neuraminidase revealed a T-antigen and a Tk-antigen and red blood cells polyagglutinability in the laboratory test. Transfusion has been reoriented by an indication of secondary preparations: deplasmatisation of red blood cells and platelets and abstention of therapeutic plasma administration. HUS evolved favorably in a few days but the child retains consequences of meningitis cerebral anoxia. Copyright © 2007 John Libbey Eurotext.

Knutson F.,Uppsala University | Osselaer J.,Catholic University of Louvain | Pierelli L.,University of Rome La Sapienza | Lozano M.,CDB | And 15 more authors.
Vox Sanguinis | Year: 2015

Background and Objectives: A photochemical treatment process (PCT) utilizing amotosalen and UVA light (INTERCEPT™ Blood System) has been developed for inactivation of viruses, bacteria, parasites and leucocytes that can contaminate blood components intended for transfusion. The objective of this study was to further characterize the safety profile of INTERCEPT-treated platelet components (PCT-PLT) administered across a broad patient population. Materials and Methods: This open-label, observational haemovigilance programme of PCT-PLT transfusions was conducted in 21 centres in 11 countries. All transfusions were monitored for adverse events within 24 h post-transfusion and for serious adverse events (SAEs) up to 7 days post-transfusion. All adverse events were assessed for severity (Grade 0-4), and causal relationship to PCT-PLT transfusion. Results: Over the course of 7 years in the study centres, 4067 patients received 19 175 PCT-PLT transfusions. Adverse events were infrequent, and most were of Grade 1 severity. On a per-transfusion basis, 123 (0·6%) were classified an acute transfusion reaction (ATR) defined as an adverse event related to the transfusion. Among these ATRs, the most common were chills (77, 0·4%) and urticaria (41, 0·2%). Fourteen SAEs were reported, of which 2 were attributed to platelet transfusion (<0·1%). No case of transfusion-related acute lung injury, transfusion-associated graft-versus-host disease, transfusion-transmitted infection or death was attributed to the transfusion of PCT-PLT. Conclusion: This longitudinal haemovigilance safety programme to monitor PCT-PLT transfusions demonstrated a low rate of ATRs, and a safety profile consistent with that previously reported for conventional platelet components. © 2015 International Society of Blood Transfusion.

Nguyen K.A.,Jean Monnet University | Hamzeh-Cognasse H.,Jean Monnet University | Palle S.,CNRS Hubert Curien Laboratory | Anselme-Bertrand I.,Jean Monnet University | And 5 more authors.
PLoS ONE | Year: 2014

Background: Platelets participate in tissue repair and innate immune responses. Sialic acid-binding immunoglobulin-like lectins (Siglecs) are well-characterized I-type lectins, which control apoptosis.Methodology/Principal Findings: We characterized the expression of Siglec-7 in human platelets isolated from healthy volunteers using flow cytometry and confocal microscopy. Siglec-7 is primarily expressed on a granular membranes and colocalized with CD62P. Siglec-7 expression was increased upon platelet activation and correlated closely with CD62P expression. Cross-linking Siglec-7 with its ligand, ganglioside, resulted in platelet apoptosis without any significant effects on activation, aggregation, cell morphology by electron microscopy analysis or secretion. We show that ganglioside triggered four key pathways leading to apoptosis in human platelets: (i) mitochondrial inner transmembrane potential (ΔΨm) depolarization; (ii) elevated expression of pro-apoptotic Bax and Bak proteins with reduced expression of antiapoptotic Bcl-2 protein; (iii) phosphatidylserine exposure and (iv), microparticle formation. Inhibition of NAPDH oxidase, PI3K, or PKC rescued platelets from apoptosis induced by Siglec-7 recruitment, suggesting that the platelet receptors P2Y1 and GPIIbIIIa are essential for ganglioside-induced platelet apoptosis.Conclusions/Significance: The present work characterizes the role of Siglec-7 and platelet receptors in regulating apoptosis and death. Because some platelet pathology involves apoptosis (idiopathic thrombocytopenic purpura and possibly storage lesions), Siglec-7 might be a molecular target for therapeutic intervention/prevention. © 2014 PLOS ONE.

Berthet J.,Jean Monnet University | Damien P.,Jean Monnet University | Hamzeh-Cognasse H.,Jean Monnet University | Arthaud C.-A.,EFS Auvergne Loire | And 7 more authors.
Clinical Immunology | Year: 2012

Platelets are currently acknowledged as cells of innate immunity and inflammation and play a complex role in sepsis. We examined whether different types of LPS have different effects on the release of soluble signaling/effective molecules from platelets. We used platelet-rich plasma from healthy volunteers and LPS from two strains of gram-negative bacteria with disparate LPS structures. We combined LPS-stimulated platelet supernatants with reporter cells and measured the PBMC cytokine secretion profiles. Upon stimulation of platelets with both Escherichia coli O111 and Salmonella minnesota LPS, the platelet LPS::TLR4 interaction activated pathways to trigger the production of a large number of molecules. The different platelet supernatants caused differential PBMC secretion of IL-6, TNFα, and IL-8. Our data demonstrate that platelets have the capacity to sense external signals differentially through a single type of pathogen recognition receptor and adjust the innate immune response appropriately for pathogens exhibiting different types of 'danger' signals. © 2012 Elsevier Inc.

Nguyen K.A.,Jean Monnet University | Hamzeh-Cognasse H.,Jean Monnet University | Sebban M.,CNRS Hubert Curien Laboratory | Fromont E.,CNRS Hubert Curien Laboratory | And 5 more authors.
PLoS ONE | Year: 2014

Background: Platelet component (PC) transfusion leads occasionally to inflammatory hazards. Certain BRMs that are secreted by the platelets themselves during storage may have some responsibility. Methodology/Principal Findings: First, we identified non-stochastic arrangements of platelet-secreted BRMs in platelet components that led to acute transfusion reactions (ATRs). These data provide formal clinical evidence that platelets generate secretion profiles under both sterile activation and pathological conditions. We next aimed to predict the risk of hazardous outcomes by establishing statistical models based on the associations of BRMs within the incriminated platelet components and using decision trees. We investigated a large (n = 65) series of ATRs after platelet component transfusions reported through a very homogenous system at one university hospital. Herein, we used a combination of clinical observations, ex vivo and in vitro investigations, and mathematical modeling systems. We calculated the statistical association of a large variety (n = 17) of cytokines, chemokines, and physiologically likely factors with acute inflammatory potential in patients presenting with severe hazards. We then generated an accident prediction model that proved to be dependent on the level (amount) of a given cytokine-like platelet product within the indicated component, e.g., soluble CD40-ligand (>289.5 pg/109 platelets), or the presence of another secreted factor (IL-13, >0). We further modeled the risk of the patient presenting either a febrile non-hemolytic transfusion reaction or an atypical allergic transfusion reaction, depending on the amount of the chemokine MIP-1α (<20.4 or >20.4 pg/109 platelets, respectively). Conclusions/Significance: This allows the modeling of a policy of risk prevention for severe inflammatory outcomes in PC transfusion. © 2014 Nguyen et al.

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