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Dive into the research topics where Jérémy Magalon is active.

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Featured researches published by Jérémy Magalon.


Arthroscopy | 2014

Characterization and Comparison of 5 Platelet-Rich Plasma Preparations in a Single-Donor Model

Jérémy Magalon; Olivier Bausset; Nicolas Serratrice; Laurent Giraudo; Houssein Aboudou; Julie Véran; Guy Magalon; Françoise Dignat-Georges; Florence Sabatier

PURPOSEnThe purpose of this study was to compare the biological characteristics of platelet-rich plasma (PRP) obtained from 4 medical devices and a preparation developed in our laboratory using a single-donor model.nnnMETHODSnTen healthy persons donated blood that was processed to produce PRP by use of 4 commercial preparation systems and a protocol developed in our laboratory. Volumes and platelet, white blood cell (WBC), and red blood cell concentrations were recorded. The platelet activation status was assessed by flow cytometry. Enzyme-linked immunosorbent assay was used to determine the concentrations of vascular endothelial growth factor, platelet-derived growth factor AB, epidermal growth factor, and transforming growth factor β1. We calculated platelet capture efficiency, relative composition, and increase factors from whole blood in platelets and WBC, as well as platelet and growth factor (GF) doses, provided from each preparation.nnnRESULTSnLeukocyte-rich PRP was obtained with RegenPRP (RegenLab, Le Mont-sur-Lausanne, Switzerland) and the Mini GPS III System (Biomet Biology, Warsaw, IN) and provides PRP with higher proportions of red blood cells, WBCs, and neutrophils than leukocyte-poor PRP obtained with the Selphyl System (Selphyl, Bethlehem, PA), Arthrex ACP (Arthrex, Naples, FL), and the preparation developed in our laboratory. The highest platelet and GF concentrations and doses were obtained with the Mini GPS III System and the preparation developed in our laboratory. Different centrifugation protocols did not show differences in the percentages of activated platelets. Finally, a positive correlation between platelet doses and all the GFs studied was found, whereas a positive correlation between WBC doses and GFs was found only for vascular endothelial growth factor and epidermal growth factor.nnnCONCLUSIONSnIn a single-donor model, significant biological variations in PRP obtained from different preparation systems were highlighted. The observed differences suggest different results for treated tissue and could explain the large variability in the clinical benefit of PRP reported in the literature.nnnCLINICAL RELEVANCEnOur findings will help clinicians to choose a system that meets their specific needs for a given indication.


BioResearch Open Access | 2012

Formulation and Storage of Platelet-Rich Plasma Homemade Product

Olivier Bausset; Laurent Giraudo; Julie Veran; Jérémy Magalon; Jean-Marie Coudreuse; G. Magalon; Christophe Dubois; Nicolas Serratrice; Françoise Dignat-George; Florence Sabatier

Abstract The platelet-rich plasma (PRP) is an autologous biotherapy based on platelet-healing properties. Here, we developed a simple and reproducible PRP purification protocol based on two successive centrifugations. We evaluated different centrifugation speeds and time-storage durations on the platelet quantity and quality. Sterility and stability of our PRP homemade product were also performed. We prepared PRP from 54 healthy volunteers. We tested activation state, reactivity, and stability of platelets by flow cytometry using basal and adenosine diphosphate (ADP)-induced P-selectin expression markers; growth factor release after platelet activation by an enzyme-linked immunosorbent assay (ELISA); platelet aggregation capacity by aggregrometry assays; clot formation and retraction by thromboelastography; and platelet morphology by ultrastructural analysis. About 130 and 250 g successive speed centrifugations further concentrated platelets while preserving their bioactivity during 6u2009h (after that, platelet functions were significantly altered). In these conditions, we obtained a highly concentrated pure PRP product (with a low leukocyte count) suitable to study platelet properties. To avoid the loss of efficacy, we recommend injecting PRP under 3u2009h after preparation.


BMJ open sport and exercise medicine | 2016

DEPA classification: a proposal for standardising PRP use and a retrospective application of available devices

Jérémy Magalon; A L Chateau; B Bertrand; M L Louis; A Silvestre; L Giraudo; J Veran; Florence Sabatier

Background/aim Significant biological differences in platelet-rich plasma (PRP) preparations have been highlighted and could explain the large variability in the clinical benefit of PRP reported in the literature. The scientific community now recommends the use of classification for PRP injection; however, these classifications are focused on platelet and leucocyte concentrations. This presents the disadvantages of (1) not taking into account the final volume of the preparation; (2) omitting the presence of red blood cells in PRP and (3) not assessing the efficiency of production. Methods On the basis of standards classically used in the Cell Therapy field, we propose the DEPA (Dose of injected platelets, Efficiency of production, Purity of the PRP, Activation of the PRP) classification to extend the characterisation of the injected PRP preparation. We retrospectively applied this classification on 20 PRP preparations for which biological characteristics were available in the literature. Results Dose of injected platelets varies from 0.21 to 5.43 billion, corresponding to a 25-fold increase. Only a Magellan device was able to obtain an A score for this parameter. Assessments of the efficiency of production reveal that no device is able to recover more than 90% of platelets from the blood. Purity of the preparation reveals that a majority of the preparations are contaminated by red blood cells as only three devices reach an A score for this parameter, corresponding to a percentage of platelets compared with red blood cells and leucocytes over 90%. Conclusions These findings should provide significant help to clinicians in selecting a system that meets their specific needs for a given indication.


Stem Cell Research & Therapy | 2014

New fat-derived products for treating skin-induced lesions of scleroderma in nude mice

Nicolas Serratrice; Laurie Bruzzese; Jérémy Magalon; Julie Veran; Laurent Giraudo; Houssein Aboudou; Djaffar Ould-Ali; Pierre Sébastien Nguyen; Olivier Bausset; Aurélie Daumas; D. Casanova; B. Granel; Lucile Andrac-Meyer; Florence Sabatier; G. Magalon

IntroductionScleroderma is characterized by cutaneous manifestations that mainly affect the hands, arms and face. As of today, there is no treatment for fibrotic skin lesions of scleroderma. Previously we generated and validated a model of scleroderma-like skin sclerosis in nude mice, appropriate to inject human derived products. We showed that the subcutaneous injection of micro-fat (MF), purified and injected using small caliber cannulas, have anti-fibrotic and pro-angiogenic effects and appears more suitable for the treatment of skin lesions of scleroderma compared to the gold standard (Coleman’s technique or macro-fat). Here we compared the long-term efficacy of micro-fat “enriched” with other therapeutic products including the stromal vascular fraction (SVF) of fat and platelet-rich plasma (PRP) from blood in our murine model of scleroderma.MethodsWe used 72 nude mice in this study. We formed six experimental groups: Macro-fat, MF, SVF, PRP, MFu2009+u2009SVF, MFu2009+u2009PRP. This project has three phases: i) Induction of skin sclerosis by daily subcutaneous injections of bleomycin (BLM) for 4 weeks in nude mice; ii) Purification and injection of the different cell therapy products; iii) Histological analyses done 8 weeks post-injections.ResultsMFu2009+u2009SVF and MFu2009+u2009PRP significantly reversed dermal and epidermal sclerosis (P <0.01). Macro-fat, SVF, PRP only corrected the dermal sclerosis (P <0.05). Epidermal sclerosis was reduced in treatments containing MF (P <0.01). MF was more stable. Products containing the SVF were associated with a significant increase of the local vascularization (P <0.01).ConclusionsAll tested substances were effective in treating skin-induced lesions of scleroderma with different levels of fibrosis and vascular improvement; MF derived products are more stable and SVF demonstrated better pro-angiogenic effects. The observed efficacy of this combination of products in the animal model provides a rationale for potential clinical applications to treat human disease.


Current Research in Translational Medicine | 2017

Long-term follow-up after autologous adipose-derived stromal vascular fraction injection into fingers in systemic sclerosis patients

Aurélie Daumas; Jérémy Magalon; Elisabeth Jouve; Romain Truillet; D. Casanova; L. Giraudo; Julie Véran; A. Benyamine; Françoise Dignat-George; Guy Magalon; Florence Sabatier; Brigitte Granel

INTRODUCTIONnHand involvement confers a substantial handicap in work and daily activities in patients with Systemic sclerosis (SSc). Autologous adipose-derived stromal vascular fraction is as an easily accessible source of cells with regenerative effects. We previously performed a phase I open-label clinical trial (NTC01813279) assessing the safety of subcutaneous injection of autologous adipose-derived stromal vascular fraction. Six and 12-month data have been reported. As patients were followed in our medical centre, we report their longer-term outcome beyond the end of the trial.nnnPATIENTS AND METHODnTwelve females, mean age 54.5±10.3 years, initially enrolled in the clinical trial were assessed during a scheduled medical care, which took place between 22 and 30months after treatment.nnnRESULTSnMultiple patient-reported outcomes showed sustained improvement, in comparison with the assessment performed just before surgery: 62.5% in the Cochin Hand Function Scale, 51.1% in the Scleroderma Health Assessment Questionnaire, 33.1% in hand pain, and 88.3% in the Raynaud Condition Score. A decrease in the number of digital ulcers number was noted. Mobility, strength and fibrosis of the hand also showed improvement. None of the 8 patients who had previously received iloprost infusion required new infusion.nnnCONCLUSIONnDespite the limits of an open label study, the data are in favour of the long-term safety of the adipose-derived stromal vascular fraction injection. Two randomized double blind, placebo-controlled trials of this therapeutic agent are ongoing in the USA (NCT02396238) and in France (NCT02558543) and will help determine the place of this innovative therapy for SSc patients.


PLOS ONE | 2015

Banking or Bankrupting: Strategies for Sustaining the Economic Future of Public Cord Blood Banks

Jérémy Magalon; Martin Maiers; Joanne Kurtzberg; Cristina Navarrete; Pablo Rubinstein; Colin Brown; Catherine Schramm; Jérôme Larghero; Sandrine Katsahian; Christian Chabannon; Christophe Picard; Alexander Platz; Alexander H. Schmidt; Gregory Katz

Background Cord blood is an important source of stem cells. However, nearly 90% of public cord blood banks have declared that they are struggling to maintain their financial sustainability and avoid bankruptcy. The objective of this study is to evaluate how characteristics of cord blood units influence their utilization, then use this information to model the economic viability and therapeutic value of different banking strategies. Methods Retrospective analysis of cord blood data registered between January 1st, 2009 and December 31st, 2011 in Bone Marrow Donor Worldwide. Data were collected from four public banks in France, Germany and the USA. Samples were eligible for inclusion in the analysis if data on cord blood and maternal HLA typing and biological characteristics after processing were available (total nucleated and CD34+ cell counts). 9,396 banked cord blood units were analyzed, of which 5,815 were Caucasian in origin. A multivariate logistic regression model assessed the influence of three parameters on the CBU utilization rate: ethnic background, total nucleated and CD34+ cell counts. From this model, we elaborated a Utilization Score reflecting the probability of transplantation for each cord blood unit. We stratified three Utilization Score thresholds representing four different banking strategies, from the least selective (scenario A) to the most selective (scenario D). We measured the cost-effectiveness ratio for each strategy by comparing performance in terms of number of transplanted cord blood units and level of financial deficit. Results When comparing inputs and outputs over three years, Scenario A represented the most extreme case as it delivered the highest therapeutic value for patients (284 CBUs transplanted) along with the highest financial deficit (USD 5.89 million). We found that scenario C resulted in 219 CBUs transplanted with a limited deficit (USD 0.98 million) that charities and public health could realistically finance over the long term. We also found that using a pre-freezing level of 18 x 108 TNC would be the most cost-effective strategy for a public bank. Conclusion Our study shows that a swift transition from strategy A to C can play a vital role in preventing public cord blood banks worldwide from collapsing.


Arthroscopy | 2018

Growth Factors Levels Determine Efficacy of Platelets Rich Plasma Injection in Knee Osteoarthritis: A Randomized Double Blind Noninferiority Trial Compared With Viscosupplementation

Marie Laure Louis; Jérémy Magalon; Elizabeth Jouve; Charles Eric Bornet; Jean Camille Mattei; C. Chagnaud; Alexandre Rochwerger; Julie Veran; Florence Sabatier

PURPOSEnTo assess the noninferiority of a single platelet-rich plasma (PRP) injection compared with hyaluronic acid (HA), to alleviate pain and enhance functional capacity in knee osteoarthritis, and identify biological characteristics of PRP that may affect their efficacy.nnnMETHODSnFifty-four patients with symptomatic knee osteoarthritis received a single injection of either PRP (26 patients) or HA (28 patients). They were assessed at baseline and at 1, 3, and 6xa0months. The primary endpoint was the change in Western Ontario and McMaster Universities Arthritis Index (WOMAC) score at 3xa0months, and secondary endpoints were responders rate (improvement of at least 5 points or 40% of WOMAC total score at 3xa0months) of pain evaluation and patients subjective satisfaction. Cell counts and the contents of vascular endothelial growth factor (VEGF), platelet-derived growth factor-AB (PDGF-AB), transforming growth factor beta 1 (TGF-β1) content of injected PRP were assessed to analyze their relationship with clinical outcome.nnnRESULTSnBoth treatments proved their improvement in knee functional status and symptom relief, with a significant decrease observed at 1xa0month on all scores except for pain VAS in PRP group and WOMAC function score in the HA group. No difference between groups regarding WOMAC and VAS scores was observed. A higher percentage of responders was observed in the PRP group (72.7%) than in the HA group (45.8%) without significance (Pxa0= .064). The quantity of injected PDGF-AB and TGF-β1 correlated with the change in WOMAC scores at 3xa0months and was lower in responders than in nonresponders (Pxa0= .009 and Pxa0= .003, respectively).nnnCONCLUSIONSnCurrent results indicated that a single injection of very pure PRP offers a significant clinical improvement in the management of knee osteoarthritis, equivalent to a single HA injection in this patient population. Moreover, a significant correlation between the doses of TGF-β1 and PDGF-AB and the worsening of WOMAC score 3xa0months after the procedure was found.nnnLEVEL OF EVIDENCEnLevel II, randomized double blind controlled trial.


Plastic and reconstructive surgery. Global open | 2016

Efficacy of Autologous Microfat Graft on Facial Handicap in Systemic Sclerosis Patients

Nolwenn Sautereau; Aurélie Daumas; Romain Truillet; Elisabeth Jouve; Jérémy Magalon; Julie Veran; D. Casanova; Yves Frances; G. Magalon; Brigitte Granel

Background: Autologous adipose tissue injection is used in plastic surgery for correction of localized tissue atrophy and has also been successfully offered for treatment of localized scleroderma. We aimed to evaluate whether patients with systemic sclerosis (SSc) and facial handicap could also benefit from this therapy. Methods: We included 14 patients (mean age of 53.8 ± 9.6 years) suffering from SSc with facial handicap defined by Mouth Handicap in Systemic Sclerosis Scale (MHISS) score more than or equal to 20, a Rodnan skin score on the face more than or equal to 1, and maximal mouth opening of less than 55 mm. Autologous adipose tissue injection was performed under local anesthesia using the technique of subcutaneous microinjection. The main objective of this study was an improvement of the MHISS score 6 months after the surgical treatment. Results: The procedure was well tolerated. We observed a mean decrease in the MHISS score of 10.7 points (±5.1; P < 0.0001) at 6 months (35% improvement). Secondary efficacy parameters assessing perioral skin sclerosis, maximum mouth opening, sicca syndrome, and facial pain significantly improved at 3 and 6 months postsurgery. At a 6-month follow-up, 75% of patients were satisfied or very satisfied of the adipose tissue microinjection therapy. Conclusions: Our study suggests that subcutaneous perioral microfat injection in patients with SSc is beneficial in the treatment of facial handicap, skin sclerosis, mouth opening limitation, sicca syndrome, and facial pain. Thus, this minimally invasive approach offers a new hope for face therapy for patients with SSc.


European Annals of Otorhinolaryngology, Head and Neck Diseases | 2017

Cell therapy and vocal fold scarring

A. Mattei; Jérémy Magalon; B. Bertrand; C. Philandrianos; Julie Veran; Antoine Giovanni

Vocal fold microstructure is complex and can be affected by laryngeal microsurgery, inducing scarring that prevents mechanical uncoupling of epithelium and muscle, leading to vibration disorder and disabling dysphonia. Treatment options presently are few, and often without efficacy for vibration, having only an impact on volume to reduce glottal closure defect. The present review of the literature had two aims: (i) to report the current state of the literature on cell therapy in vocal fold scarring; and (ii) to analyze the therapeutic interest of the adipose-derived stromal vascular fraction in the existing therapeutic armamentarium. A PubMed® search conducted in September 2016 retrieved English or French-language original articles on the use of stem cells to treat vocal fold scarring. Twenty-seven articles published between 2003 and 2016 met the study selection criteria. Mesenchymal stem cells were most widely used, mainly derived from bone marrow or adipose tissue. Four studies were performed in vitro on fibroblasts, and 18 in vivo on animals. End-points comprised: (i) scar analysis (macro- and micro-scopic morphology, viscoelastic properties, extracellular matrix, fibroblasts); and (ii) assessment of stem cell survival and differentiation. The studies testified to the benefit of mesenchymal stem cells, and especially those of adipose derivation. The stromal vascular fraction exhibits properties that might improve results by facilitating production logistics.


Arthritis Research & Therapy | 2017

Increased serum levels of fractalkine and mobilisation of CD34+CD45− endothelial progenitor cells in systemic sclerosis

A. Benyamine; Jérémy Magalon; Sylvie Cointe; Romaric Lacroix; Laurent Arnaud; Nathalie Bardin; Pascal Rossi; Yves Frances; Fanny Bernard-Guervilly; G. Kaplanski; Jean-Robert Harlé; P.J. Weiller; Philippe Berbis; David Braunstein; Elisabeth Jouve; Nathalie Lesavre; Françoise Couranjou; Françoise Dignat-George; Florence Sabatier; Pascale Paul; Brigitte Granel

BackgroundThe disruption of endothelial homeostasis is a major determinant in the pathogenesis of systemic sclerosis (SSc) and is reflected by soluble and cellular markers of activation, injury and repair. We aimed to provide a combined assessment of endothelial markers to delineate specific profiles associated with SSc disease and its severity.MethodsWe conducted an observational, single-centre study comprising 45 patients with SSc and 41 healthy control subjects. Flow cytometry was used to quantify circulating endothelial microparticles (EMPs) and CD34+ progenitor cell subsets. Colony-forming unit-endothelial cells (CFU-ECs) were counted by culture assay. Circulating endothelial cells were enumerated using anti-CD146-based immunomagnetic separation. Blood levels of endothelin-1, vascular endothelial growth factor (VEGF) and soluble fractalkine (s-Fractalkine) were evaluated by enzyme-linked immunosorbent assay. Disease-associated markers were identified using univariate, correlation and multivariate analyses.ResultsEnhanced numbers of EMPs, CFU-ECs and non-haematopoietic CD34+CD45− endothelial progenitor cells (EPCs) were observed in patients with SSc. Patients with SSc also displayed higher serum levels of VEGF, endothelin-1 and s-Fractalkine. s-Fractalkine levels positively correlated with CD34+CD45− EPC numbers. EMPs, s-Fractalkine and endothelin-1 were independent factors associated with SSc. Patients with high CD34+CD45− EPC numbers had lower forced vital capacity values. Elevated s-Fractalkine levels were associated with disease severity, a higher frequency of pulmonary fibrosis and altered carbon monoxide diffusion.ConclusionsThis study identifies the mobilisation of CD34+CD45− EPCs and high levels of s-Fractalkine as specific features of SSc-associated vascular activation and disease severity. This signature may provide novel insights linking endothelial inflammation and defective repair processes in the pathogenesis of SSc.

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Florence Sabatier

French Institute of Health and Medical Research

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G. Magalon

Boston Children's Hospital

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D. Casanova

Boston Children's Hospital

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A. Benyamine

Aix-Marseille University

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A. Mattei

Aix-Marseille University

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