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Dive into the research topics where F. Bellier-Waast is active.

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Featured researches published by F. Bellier-Waast.


Journal of Immunology | 2016

Functional Langerinhigh-Expressing Langerhans-like Cells Can Arise from CD14highCD16− Human Blood Monocytes in Serum-Free Condition

Gaëlle Picarda; Coraline Chéneau; Jean-Marc Humbert; Gaëlle Bériou; Paul Pilet; Jérôme C. Martin; Franck Duteille; Pierre Perrot; F. Bellier-Waast; Michèle Heslan; Fabienne Haspot; Fabien Guillon; Régis Josien; Franck Halary

Langerhans cells (LCs) are epithelial APCs that sense danger signals and in turn trigger specific immune responses. In steady-state, they participate in the maintenance of peripheral tolerance to self-antigens whereas under inflammation LCs efficiently trigger immune responses in secondary lymphoid organs. It has been demonstrated in mice that LC-deprived epithelia are rapidly replenished by short half-life langerin-expressing monocyte-derived LCs (MDLCs). These surrogate LCs are thought to be progressively replaced by langerinhigh LCs arising from self-renewing epithelial precursors of hematopoietic origin. How LCs arise from blood monocytes is not fully understood. Hence, we sought to characterize key factors that induce differentiation of langerinhigh-expressing monocyte-derived Langerhans-like cells. We identified GM-CSF and TGF-β1 as key cytokines to generate langerinhigh-expressing cells but only in serum-free conditions. These cells were shown to express the LC-specific TROP-2 and Axl surface markers and contained Birbeck granules. Surprisingly, E-cadherin was not spontaneously expressed by these cells but required a direct contact with keratinocytes to be stably induced. MDLCs induced stronger allogeneic T cell proliferations but released low amounts of inflammatory cytokines upon TLR stimulation compared with donor-paired monocyte-derived dendritic cells. Immature langerinhigh MDLCs were responsive to MIP-3β/CCL20 and CTAC/CCL27 chemokine stimulations. Finally, we demonstrated that those cells behaved as bona fide LCs when inserted in a three-dimensional rebuilt epithelium by becoming activated upon TLR or UV light stimulations. Collectively, these results prompt us to propose these langerinhigh MDLCs as a relevant model to address LC biology–related questions.


Spinal Cord | 2015

Sepsis of the hip due to pressure sore in spinal cord injured patients: advocacy for a one-stage surgical procedure

M Le Fort; J. Rome-Saulnier; F. Lejeune; F. Bellier-Waast; Sophie Touchais; P. Kieny; F Duteille; B. Perrouin-Verbe

Study design:Retrospective study reporting characteristics and management of septic arthritis of the hip due to pressure sores in spinal cord-injured patients.Objectives:To describe clinical and biological data of septic arthritis of the hip and its treating management.Setting:The database of the regional SCI referral center, Nantes, France.Methods:We retrospectively collected data from 33 cases of septic arthritis of the hip in the medical files of 26 patients.Results:We analyzed 33 cases of septic arthritis of the hip treated in one French referent center for spinal cord-injured patients from January 1988 to December 2009. Most patients had a thoracic complete paraplegia and nearly two-third (17 out of 26) had no systematic follow-up. In 25 out of 33 cases, the septic arthritis of the hip was due to a trochanteric pressure sore. The causal pressure sore was most frequently associated with a persistent drainage. The standard radiological examination led to the diagnosis in 30 cases and, in 7 questionable cases, magnetic resonance imaging was more contributory. Surgery always consisted of a wide carcinological-like excision and of a subtrochanteric proximal femoral resection including both greater and lesser trochanters. A musculocutaneous flap was realized for all cases and the choice of the muscle depended on the localization of the causal pressure sore but also of the remaining choices, as most of the patients had already undergone a prior surgery. An antibiotic treatment was adapted to multiple samples during surgery.Conclusion:We do advocate for a one-stage procedure including a subtrochanteric proximal femoral resection and a musculocutaneous flap.


Annals of Plastic Surgery | 2009

Coverage of clavicular area by a pectoralis minor pedicle flap: anatomical study and description of three clinical cases.

Ludovic Bourdais; F. Bellier-Waast; Pierre Perrot; Jean Delpierre; Michel Pannier; Franck Duteille

As the data in the literature concerning the vascularization of the pectoralis minor were conflicting, we conducted a new anatomic study on cadavers preliminary to clinical application of a pedicle flap for clavicular coverage in 3 patients. Twenty flaps were dissected, yielding numerous anatomic variations. In all cases, the principal arteries penetrated the muscle in its upper part, either posteriorly or posterolaterally.This anatomic study justified the use of the pectoralis minor as a pedicle flap, with turnover just below the coracoid process. Accordingly, 3 cases of clavicular defects were treated successfully.Reports in the literature propose an adipofascial turnover flap or a pectoralis major flap for clavicular coverage. The pectoralis minor pedicle flap is easy to dissect and reproducible, involving minor esthetic sequelae and no functional complications. This flap, which has never been described in this application, would appear to be suitable for first-line treatment in this indication.


Frontiers in Immunology | 2018

Ex Vivo Expanded Human Non-Cytotoxic CD8+CD45RClow/− Tregs Efficiently Delay Skin Graft Rejection and GVHD in Humanized Mice

Séverine Bézie; Dimitri Meistermann; Laetitia Boucault; Stéphanie Kilens; Johanna Zoppi; Elodie Autrusseau; Audrey Donnart; Véronique Nerrière-Daguin; F. Bellier-Waast; Eric Charpentier; Franck Duteille; Laurent David; Ignacio Anegon; Carole Guillonneau

Both CD4+ and CD8+ Tregs play a critical role in the control of immune responses and immune tolerance; however, our understanding of CD8+ Tregs is limited while they are particularly promising for therapeutic application. We report here existence of highly suppressive human CD8+CD45RClow/− Tregs expressing Foxp3 and producing IFNγ, IL-10, IL-34, and TGFβ to mediate their suppressive activity. We demonstrate that total CD8+CD45RClow/− Tregs can be efficiently expanded in the presence of anti-CD3/28 mAbs, high-dose IL-2 and IL-15 and that such expanded Tregs efficiently delay GVHD and human skin transplantation rejection in immune humanized mice. Robustly expanded CD8+ Tregs displayed a specific gene signature, upregulated cytokines and expansion in the presence of rapamycin greatly improved proliferation and suppression. We show that CD8+CD45RClow/− Tregs are equivalent to canonical CD4+CD25highCD127low/− Tregs for suppression of allogeneic immune responses in vitro. Altogether, our results open new perspectives to tolerogenic strategies in human solid organ transplantation and GVHD.


Annales De Chirurgie Plastique Esthetique | 2015

Brûlures des mains de l’enfant et gants Aquacel® Burn, une alternative aux hospitalisations prolongées. À propos de 20 cas

P. Ridel; Pierre Perrot; M.-V. Truffandier; F. Bellier-Waast; Franck Duteille

AIM OF THE STUDY Occlusive dressings for second-degree hand burns in children must prevent infection and promote healing. For good management of analgesia, these treatments often require children to be hospitalized. Our goal was to find an alternative to conventional care protocol that would reduce the number of dressings and therefore the length of hospitalization. We report our experience with the use of Aquacel(®) Burn. PATIENTS AND METHOD Non-randomized monocentric prospective study was conducted from 2012 to 2014. The glove was used in the operating room within 72hours after the burn in children younger than 15 years old with isolated superficial to deep 2nd degree hand burns. Once the glove was perfectly stuck to the burn, the children could go back home. We saw them 10 to 12 days after the accident to be sure there was no indication of skin graft. RESULTS Twenty gloves were used in 16 children aged from 16 months to 13 years. The average length of stay (ALOS) was five days to put the glove on and one day to remove it. Four hands were grafted. CONCLUSION Once we get used to the product, Aquacel(®) Burn gloves have reduced the ALOS before skin graft in cases of isolated hand burns in children.


Transplantation | 2018

Rapamycin-Based Expansion of Natural CD8+Tregs for Cell Therapy

Séverine Bézie; Véronique Daguin; F. Bellier-Waast; Franck Duteille; Ignacio Anegon; Carole Guillonneau

Introduction We identified a subset of natural regulatory CD8+ T cells in peripheral blood of healthy volunteers characterized by the low expression of CD45RC surface molecule. These CD8+Tregs can inhibit allogeneic T cell proliferation in vitro through secretion of IFNg, IL-10, TGFbeta and IL-34. To date, there is no clinical study using CD8+Tregs as a cell-based therapy. Considering their potential for cellular therapy, we set up a process to expand these CD8+Tregs in a short term culture. Materials and Methods Tregs were expanded for 14 days with anti-CD3/CD28 mAbs or allogeneic APCs in presence of 1000U/ml IL-2, 10ng/ml IL-15, and with or without cyclosporine A (45ng/ml), rapamycin (45ng/ml), methylprednisolone (500pg/ml), tacrolimus (2ng/ml) or mycophenolate mofetil (1&mgr;g/ml). Suppressive function of CD8+Tregs was assessed in vitro on syngeneic CD4+CD25-T cells stimulated by alloAPCs, and in vivo into NSG mice infused with PBMCs and grafted or not with allogeneic human skin for allograft survival and xenogeneic GVHD studies. Results We demonstrated that natural CD8+Tregs can be efficiently expanded until 2000 fold in 14 days, when stimulated with either allogeneic APCs or anti-CD3 and anti-CD28 mAbs. High dose of IL-2 and IL-15 were required to maintain CD8+Tregs survival. After expansion, CD8+Tregs suppressive capacity was preserved and even increased in vitro, in accordance with their higher expression of immunoregulatory cytokines, while they displayed no cytotoxic activity. Furthermore, transfer of ex-vivo expanded CD8+Tregs allowed to delay GVHD development and allogeneic skin graft rejection in humanized mice models. As usually administered to patients after transplantation, we analyzed the impact of culture medium supplementation with immunosuppressive drugs during expansion. Interestingly, addition of rapamycin improved both CD8+Tregs expansion yield and suppressive activity by 16 and 1.6 fold respectively. Conclusions We demonstrated that natural CD8+Tregs can be greatly expanded while improved in their suppressive function particularly when cultured in presence of rapamycin, proving their relevance for cell therapy.


Journal of Plastic Reconstructive and Aesthetic Surgery | 2018

Ten years of myocutaneous flaps for pressure ulcers in patients with spinal lesions: Analysis of complications in the framework of a specialised medical-surgical pathway

Chloë Lefèvre; F. Bellier-Waast; Florence Lejeune; Franck Duteille; Pierre Kieny; Marc Le Fort; B. Perrouin-Verbe

INTRODUCTION The objective of the study is to analyse complications associated with surgery for pelvic pressure ulcers in terms of their frequency, nature and rate of surgical revisions. The secondary aims are to analyse the rate of recurrence, length of stay and time to healing, and to determine factors associated with complications and recurrence. METHODS It is a single-centre, retrospective cohort study with a 10-year follow-up setting in Nantes University Hospital, France, a specialist centre for spinal cord injury (SCI). All patients who were admitted to the Neurological Physical Medicine and Rehabilitation (PMR) department for surgery (flap coverage) for pelvic pressure ulcers between 1st of January 2004 and 30th September 2014 were included. The main outcome measures were the rate of complications, rate of recurrence, length of stay and time to healing, as well as factors associated with complications and recurrence. RESULTS One hundred and sixty-six patients underwent 252 flap procedures in 239 operations. The majority of patients had SCI (78.3%). The ulcer sites were mainly ischial (67%), sacral (20%) and trochanteric (12%). Gluteus maximus was used most often (75.3% of flaps) (ischial and sacral ulcers), followed by tensor fascia lata (16.2%) (trochanteric ulcers). The rate of complications that delayed return to wheelchair at 6 weeks was 34.5%. The factors associated with complications were more than one surgical ulcer and drainage time greater than 10 days. The rate of recurrence was 20.04%. The factors related to recurrence were young age, scoliosis and an oblique pelvis. CONCLUSIONS Management within a specialised medical-surgical pathway limited post-operative complications and recurrences in this sample of subjects who mostly had SCI.


Annals of Physical and Rehabilitation Medicine | 2015

Verrucous carcinoma on a chronic sacral pressure ulcer in a patient with meningomyelocele. Case report and review of the literature.

C. Lefèvre; O. Hamel; G. Gadbled; F. Lejeune; F. Bellier-Waast; E. Cassagnau; B. Perrouin-Verbe

Mr G. was born in 1977 with meningomyelocele, operated in 1978, and presented complete AIS A T12 paraplegia and hydrocephalus with moderate mental retardation. His surgical antecedents were: ventriculoperitoneal shunt, augmentation enterocystoplasty and anti-reflux surgery in 1990, Salter pelvic osteotomy + Sharrard psoas muscle transfer in 1994. In 2004 we managed the patient for the first time, for a sacral pressure ulcer, in the form of a cryptic and keratotic lesion. It was already a recurrence. In 2005, purulent discharge makes us practice an MRI, showing subcutaneous infiltration involving the sacrum (sacral osteomyelitis is suspected) and a cryptic zone in contact with the rectal wall. A first musculocutaneous flap permitted a first biopsy of the sacral lesion in June 2005. Histological examination revealed chronic ulceration compatible with a diagnosis of pressure ulcer. The initial postoperative course was favourable, but at the beginning of 2006, purulent discharge on sacrum recurred, explained at MRI by persistence of a blind perineal fistula along the levator ani muscles and another fistula extending towards the coccyx (no signs of intestinal fistula). After two flap revisions in 2006 and 2007 allowing evacuation of large infected haematoma, closure of fistulas and after adapted dual-agent antibiotic therapy (against always the same germ: Proteus mirabilis), the patient has healed and regained his autonomy. All histological examinations were compatible with a chronic wound with no sign of malignancy. No complication was observed during a 3-year period of outpatient follow-up. An annual follow-up CT urography incidentally revealed a sacral mass (Fig. 1). MRI confirmed the presence of an infiltration with a paraspinal collection extending from L3 to the sacrum associated with sacral bone destruction, suggesting an infectious process (Fig. 2). The patient was admitted to hospital for a infected stage 3 sacral pressure ulcer and new fistulas. He was malnourished, had chronic anemia and signs of sepsis. In a multidisciplinary consultation meeting (MCM), we decided to practice excision of the pressure ulcer and exploration of the fistulas (no intestinal fistula founded), one on the right hip. Histological examination revealed the presence of epidermal cysts with no histological signs of malignancy. Triple agent antibiotic therapy was initiated. An MRI performed in February 2011 showed no improvement, so the patient was reoperated for an oncologic-like resection including: sacrum, right sacro-iliac joint and the right Sharrard psoas muscle transfer and resection of the head and neck of the


Annales De Chirurgie Plastique Esthetique | 2011

Microchirurgie et séquelles de brûlures : quelles applications pratiques ?Microsurgery and burn sequelae: What kind of indication?

Franck Duteille; F. Bellier-Waast; Pierre Perrot

Resume Des la naissance de la microchirurgie, des applications dans la prise en charge des brulures ont ete rapportees, tant au stade aigu que de sequelles. En effet, des 1975, Sharzer et al. rapportent une serie de lambeaux libres realises avec succes dans ce contexte. Au fil des ans, la litterature s’est etoffee, demontrant l’interet des procedures microchirurgicales pour traiter certaines sequelles de brulures, mais egalement leurs difficultes techniques en partie liees a la disponibilite de vaisseaux receveurs de qualite. Depuis, de nouvelles technologies comme l’expansion tissulaire et les dermes artificiels se sont ajoutes a l’arsenal therapeutique. Il est donc legitime de se poser la question de la place actuelle de la microchirurgie dans le traitement des sequelles de brulure.The use of microsurgery in the management of burn sequelae is not a new idea and free flaps have been used in this context since the 1970s. New technologies like negative pressure treatment and skin substitute have certainly decreased the indication of free flaps. The authors with their experience combined to a review of the literature, try to clarify these indications for each anatomical location. From a technical point of view, they find that realizing a free flap for these patients is more complicated (venous damage, lack of donor site who has been burned…). Despite this, microsurgery must still belong in the decision tree and there are some irreplaceable indication specially for hand reconstruction.


Annales De Chirurgie Plastique Esthetique | 2011

Microchirurgie et séquelles de brûlures : quelles applications pratiques ?

Franck Duteille; F. Bellier-Waast; Pierre Perrot

Resume Des la naissance de la microchirurgie, des applications dans la prise en charge des brulures ont ete rapportees, tant au stade aigu que de sequelles. En effet, des 1975, Sharzer et al. rapportent une serie de lambeaux libres realises avec succes dans ce contexte. Au fil des ans, la litterature s’est etoffee, demontrant l’interet des procedures microchirurgicales pour traiter certaines sequelles de brulures, mais egalement leurs difficultes techniques en partie liees a la disponibilite de vaisseaux receveurs de qualite. Depuis, de nouvelles technologies comme l’expansion tissulaire et les dermes artificiels se sont ajoutes a l’arsenal therapeutique. Il est donc legitime de se poser la question de la place actuelle de la microchirurgie dans le traitement des sequelles de brulure.The use of microsurgery in the management of burn sequelae is not a new idea and free flaps have been used in this context since the 1970s. New technologies like negative pressure treatment and skin substitute have certainly decreased the indication of free flaps. The authors with their experience combined to a review of the literature, try to clarify these indications for each anatomical location. From a technical point of view, they find that realizing a free flap for these patients is more complicated (venous damage, lack of donor site who has been burned…). Despite this, microsurgery must still belong in the decision tree and there are some irreplaceable indication specially for hand reconstruction.

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Franck Duteille

French Institute of Health and Medical Research

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Gaëlle Picarda

La Jolla Institute for Allergy and Immunology

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