Laurence Michel

Laurence Michel
French Institute of Health and Medical Research | Inserm · Dermatologie Hôpital Saint-Louis

Bachelor of Pharmacy

About

226
Publications
18,992
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
5,357
Citations
Introduction
Skills and Expertise

Publications

Publications (226)
Article
Crucial for skin homeostasis, synthesis and degradation of extracellular matrix components are orchestrated by dermal fibroblasts. During aging, alterations of component expression, such as collagens and enzymes, lead to reduction of the mechanical cutaneous tension and defects of skin wound healing. The aim of this study was to better understand t...
Article
Full-text available
Healing of complex wounds requires dressings that must, at least, not hinder and should ideally promote the activity of key healing cells, in particular fibroblasts. This in vitro study assessed the effects of three wound‐dressings (a pure Ca ²⁺ alginate: Algostéril®, a Ca ²⁺ alginate + carboxymethylcellulose: Biatain alginate® and a polyacrylate i...
Preprint
Full-text available
Caspase-8 deficiency in the epidermis (caspase-8 EKO ) results in cutaneous inflammation resembling pustular psoriasis, triggered by necroptotic cell death of keratinocytes. Necroptosis is a highly proinflammatory form of programmed necrosis due to the release of intracellular molecules called alarmins, which can act as inflammatory mediators. Howe...
Article
Keloid scars are hypertrophic and proliferating pathological scars extending beyond the initial lesion and without tendency to regression. Usually, keloids are considered and treated as a single entity but clinical observations suggest heterogeneity in keloid morphologies with distinction of superficial/extensive and nodular entities. Within a kelo...
Article
Full-text available
Natural Killer (NK) cells participate in the defense against infection by killing pathogens and infected cells and secreting immuno-modulatory cytokines. Defects in NK cell activity have been reported in obese, diabetic, and elderly patients that are at high risk of developing infected chronic wounds. Calcium alginate dressings are indicated for th...
Article
Background: Advanced-stage cutaneous T-cell lymphomas (CTCLs) are rare, usually refractory, and fatal diseases. Case series have suggested that allogeneic haematopoietic stem cell transplantation (HSCT) might improve the prognosis of advanced-stage CTCLs. The objective of this study was to investigate the effect of allogeneic HSCT compared with no...
Article
Innovative Pickering emulsions co-encapsulating two active pharmaceutical ingredients (API) were formulated for a topical use. An immunosuppressive agent, either cyclosporine A (CysA) or tacrolimus (TAC), was encapsulated at high drug loading in biodegradable and biocompatible poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NP). These NP stabi...
Article
Full-text available
Skin wounds and compromised wound healing are major concerns for the public. Although skin wound healing has been studied for decades, the molecular and cellular mechanisms behind the process are still not completely clear. The systemic responses to trauma involve the body’s inflammatory and immunomodulatory cellular and humoral networks. Studies o...
Article
Background Primary cutaneous lymphomas are a group of T- (CTCL) and B-cell (CBCL) malignancies. These diseases have different clinical presentations and prognosis. Our knowledge on their epidemiology is limited. Aim of this review was to summarise recent findings on the incidence of CTCL and CBCL, how they change over time, and to describe possible...
Article
Cutaneous involvement of chronic graft-versus-host disease (cGVHD) has a wide range of manifestations including a lichenoid form with a currently assumed mixed Th1/Th17 signature and a sclerotic form with Th1 signature. Despite substantial heterogeneity of innate and adaptive immune cells recruited to the skin and of the different clinical manifest...
Article
Introduction La peau au cours de l’âge subit plusieurs changements morphologiques: apparition de rides, perte de tonicité, associés à des problèmes de cicatrisation comme les escarres liés à une altération de la fermeture des plaies. Notre comparaison précédente du protéome de fibroblastes de peaux jeunes et matures avait mis en évidence des différ...
Article
Introduction Cancer-associated fibroblasts (CAFs), a component of tumor microenvironment, play a key role in oncogenesis and promote growth, invasion, metastasis and chemo-resistance of tumor cells. Our previous RNAseq results brought evidence of the contribution of dermal fibroblasts obtained from cutaneous T-cell lymphoma (CTCL) lesions to suppor...
Article
Background Clinical and histological diagnosis of Sézary syndrome (SS) and mycosis fungoides (MF) is challenging in routine. We investigated five blood markers previously described for SS (T‐plastin, Twist, KIR3DL2, NKp46 and Tox) in a prospective validation cohort of patients. Methods The markers were analyzed by RT‐q‐PCR on peripheral blood leuc...
Article
Full-text available
Un des enjeux majeurs de ce XXI e siècle est la lutte contre le vieillissement, défini comme un ensemble de mécanismes physiologiques altérant les capacités physiques et intellectuelles de l’organisme. Le vieillissement de la peau n’est qu’un trait visible de ce processus. Il est associé à des défauts de cicatrisation majeurs liés à l’altération de...
Article
Introduction Le microenvironnement tissulaire joue un rôle clé dans l’oncogenèse et favorise la croissance, l’invasion, les métastases et la résistance à la chimio-prévention des cellules tumorales. Notre objectif est de déterminer quelle est la contribution du microenvironnement cutané mésenchymateux dans les lésions tumorales des lymphomes T cuta...
Article
Full-text available
Introduction Les cellules tueuses naturelles (NK) participent à la réponse immunitaire innée en tuant les cellules infectées ou tumorales. Lors d’une blessure, les cellules NK sont mobilisées sur le site dans les 24 premières heures et persistent pendant 3 à 5 jours. L’activation des cellules NK permet de diminuer localement le risque infectieux et...
Article
Introduction L’alopécie frontale fibrosante (AFF) est une alopécie cicatricielle, caractérisée par une alopécie en bande de la ligne frontale et considérée comme une variante clinique du lichen plan pilaire (LPP), deux pathologies auto-immunes avec une physiopathologie proche et une étiologie inconnue. Si notre étude histologique récente a montré p...
Article
Introduction Les lymphomes cutanés primitifs sont un groupe hétérogène de lymphomes T cutanés (LTC) et de lymphomes B cutanés (LBC). Nous avons peu d́informations sur les caractéristiques des patients atteints de ces maladies et leurs stades initiaux. Malgré plusieurs publications nationales européennes il existe peu de données sur ĺévolution de le...
Article
Full-text available
Background Primary cutaneous lymphomas (PCLs) are a heterogeneous group of T‐cell (CTCL) and B‐cell (CBCL) malignancies. Little is known about their epidemiology at initial presentation in Europe and about potential changes over time. Objectives The aim of this retrospective study was to analyse the frequency of PCLs in the French Cutaneous Lympho...
Article
Full-text available
Ciguatera fish poisoning (CFP) is caused by the consumption of fish contaminated with ciguatoxins (CTXs). The most distressing symptoms are cutaneous sensory disturbances, including cold dysesthesia and itch. CTXs are neurotoxins known to activate voltage-gated sodium channels (Nav) but no specific treatment exists. Peptidergic neurons have been cr...
Article
Full-text available
The prevalence of psychological disorders in patients with common skin diseases was assessed in a large representative sample of the French adult population. General health, as measured by the EQ5D score, was significantly lower if patients reported having rosacea, atopic dermatitis, urticaria, fungal infections, psoriasis or acne. The proportions...
Article
Scleromyxedema is a rare skin and systemic mucinosis that is usually associated with monoclonal gammopathy (MG). In this French, multicenter, retrospective study of 33 patients, we investigated the clinical and therapeutic features of MG-associated scleromyxedema. Skin molecular signatures were analyzed using a transcriptomic approach. Skin symptom...
Article
Introduction Le mycosis fongoïde (MF) et son variant leucémique, le syndrome de Sézary (SS), sont les formes les plus fréquentes des lymphomes T cutanés (LTC). Leur diagnostic clinique et histologique peut être difficile. Notre équipe a décrit quatre marqueurs sanguins prometteurs du SS : Twist, T-plastine, NKp46 et KIR3DL2. De plus Tox a été décri...
Article
Introduction L’AFF est une alopécie cicatricielle lymphocytaire considérée comme un sous-type clinique du LPP. Son incidence augmente de manière significative dans les pays développés depuis sa description en 1994. Les études cas-témoins trouvent de manière répétée chez les patients une surreprésentation des sujets utilisant de manière régulière de...
Article
Introduction L’alopécie frontale fibrosante (AFF) est une alopécie cicatricielle d’incidence croissante, affectant principalement les femmes ménopausées. Elle est caractérisée par une alopécie en bande de la ligne frontale. Son étiologie est inconnue. L‘histologie et la présentation clinique évoquent une forme particulière de lichen plan pilaire (L...
Article
Introduction Dans cette étude, nous avons développé une émulsion de pickering co-encapsulant un médicament immunosuppresseur (ciclosporine A ou tacrolimus) dans des nanoparticules de PLGA (NP) biodégradables et biocompatibles, qui stabilisent la phase huileuse contenant du calcitriol. L’objectif est de quantifier leurs effets biologiques in vitro s...
Article
Introduction La peau avec le temps subit des changements morphologiques et physiologiques, conduisant à des problèmes de cicatrisation souvent difficiles à résoudre dans la population âgée. Afin de comprendre les paramètres moléculaires impliqués dans les défauts de cicatrisation cutanée observés avec l’âge, nous avons étudié l’altération de la pro...
Article
Introduction Le remodelage physiologique du système immunitaire avec l’âge, appelé « immunosénescence », contribue à la susceptibilité des personnes âgées aux infections. L’objectif de cette étude était de caractériser l’immunosénescence des lymphocytes T conventionnels et non conventionnels résidents de la peau chez l’homme. Matériel et méthodes...
Article
Introduction L’objectif de ce travail était d’étudier l’impact psychologique des dermatoses les plus fréquentes à partir des données épidémiologiques de l’enquête Objectifs Peau. Matériel et méthodes Un échantillon de 20 012 individus représentatifs de la population française de plus de 15 ans a été spécifiquement créé selon la méthode habituelle...
Article
Normal aging is associated with an impaired systemic immune response contributing to an increased susceptibility to infectious diseases. The aim of this study was to compare the lymphocyte phenotype in human skin from old and young healthy subjects. Skin samples from donors were used for explant cultures before flow cytometry analysis. Our results...
Article
Full-text available
Objective Hair greying (i.e., canities) is a component of chronological aging and occurs regardless of gender or ethnicity. Canities is directly linked to the loss of melanin and increase in oxidative stress in the hair follicle and shaft. To promote hair pigmentation and reduce the hair greying process, an agonist of α‐melanocyte‐stimulating hormo...
Article
Introduction La maladie de Still de l’adulte (MSA) est une maladie rare associée à une activation macrophagique, neutrophilique et à une sécrétion incontrôlée de cytokines pro-inflammatoires. La présentation dermatologique de la MSA est caractérisée par une éruption cutanée typique évanescente (ECTE), mais de nombreux cas d’éruption cutanée atypiqu...
Article
Full-text available
In human lung fibrotic lesions, fibroblasts were shown to be closely associated with immature dendritic cell (DC) accumulation. The aim of the present pilot study was to characterize the role of pulmonary fibroblasts on DC phenotype and function, using co-culture of lung fibroblasts from patients with idiopathic pulmonary fibrosis (IPF) and from co...
Article
Introduction Le vieillissement de la peau est caractérisé, en partie, par une perte de tissu adipeux sous-cutané, avec modification de la distribution de la graisse corporelle, perte de réponse à l’insuline et de capacité de stockage des lipides. Les capacités de différenciation des pré-adipocytes en adipocytes sont également altérées avec l’âge, c...
Article
Background Qualitative research is often used in the field of general medicine. Our objective was to evaluate the quality of published qualitative studies conducted using individual interviews or focus groups centred on patients monitored in general practice. Methods We have undertaken a review of the literature in the PubMed and Embase databases...
Article
Full-text available
Maintenance and regeneration of adult tissues are dependent of stem/progenitor cells through their self-renewal and differentiation potential. Mesenchymal stem cells (MSCs) promote tissue regeneration such as adipose one through their differentiation potential into adipocytes(1) . Although MSCs were first isolated from bone marrow (BM), other sourc...
Article
Sézary syndrome (Sz) is a malignancy of skin-homing CD4(+) memory T-cells, clinically characterized by erythroderma, lymphadenopathy and blood involvement. Distinction of Sz from erythroderma secondary to inflammatory skin diseases (EID) is often challenging. Recent studies identified recurrent mutations in epigenetic enzymes involved in DNA modifi...
Article
Full-text available
Systemic sclerosis (SSc) is a heterogeneous autoimmune disease characterized by auto-Ab production and predominant T-cell infiltration, resulting in excessive fibrosis within the skin and internal organs.¹ The various cytokines and chemokines produced by the activated T cells contribute to recruiting additional inflammatory cells and to fibroblast...
Article
Background: KIR3DL2, an inhibitory receptor expressed by NK-cells and a subset of normal CD8(+) T cells, is aberrantly expressed in neoplastic cells in transformed mycosis fungoides and Sézary Syndrome. Anti-KIR3DL2 targeted antibody therapy has shown potent activity in preclinical models for these diseases. Objectives: To examine the expression...
Article
Differentiation between Sézary syndrome (SS) and erythrodermic inflammatory dermatoses (EID) can be challenging and a number of studies have attempted to identify characteristic immunophenotypic changes and molecular biomarkers in Sézary cells that could be useful as additional diagnostic criterion. In this European multicenter study the sensitivit...
Article
Full-text available
Background: Melanoma incidence is higher in patients affected by Parkinson's disease (PD) and vice versa, but the genetic link shared by both diseases is unknown. As PARK2 is both a tumor suppressor gene and frequently mutated in young onset PD, we evaluated the role of PARK2 in melanoma predisposition and progression. Methods: An in-depth PARK2...
Article
Introduction L’alopécie androgénétique masculine (AAGM) est héréditaire dans plus de 80 % des cas. La perte de cheveux est progressive et commence sur les lobes frontaux et le sommet du vertex, avec une prévalence qui augmente avec l’âge. Le but de cette étude est d’identifier des biomarqueurs moléculaires associés à l’AAGM prématurée afin de détec...
Article
Introduction Plusieurs biomarqueurs sanguins (BM) comme KIR3DL2, Twist, T-plastine, et NKp46 ont ete specifiquement identifies dans le sang de patients ayant un syndrome de Sezary. Leur combinaison permet de diagnostiquer 100 % des syndromes de Sezary non traites. L’objectif de notre etude etait d’evaluer l’expression de ces biomarqueurs sanguins c...
Article
In human lung fibrotic lesions, fibroblasts were shown to be closely associated with immature dendritic cell (DC) accumulation. The aim of the present pilot study was to characterize the role of pulmonary fibroblasts on DC phenotype and function, using co-culture of lung fibroblasts from patients with idiopathic pulmonary fibrosis (IPF) and from co...
Article
Full-text available
Purpose: Advanced-stage mycosis fungoides (MF; stage IIB to IV) and Sézary syndrome (SS) are aggressive lymphomas with a median survival of 1 to 5 years. Clinical management is stage based; however, there is wide range of outcome within stages. Published prognostic studies in MF/SS have been single-center trials. Because of the rarity of MF/SS, on...
Article
Dermal fibroblasts play a key role in maintaining skin homeostasis by synthesizing and degrading extracellular matrix components. During aging, they are subjected to changes, such as the loss of type I collagen expression and an increased synthesis of metalloproteinase I, leading to fragmentation of collagen fibrils with consequent reduction of the...
Article
The Journal of Investigative Dermatology publishes basic and clinical research in cutaneous biology and skin disease.
Article
Full-text available
Introduction: Transforming growth factor (TGF)-β and interleukin (IL)-13 play a crucial role in the pathogenesis of systemic sclerosis (SSc), partly through activation of collagen production that leads to fibrosis. The aim of the present study was to determine whether TFG-β alters IL-13 production in T lymphocytes from patients with SSc from that...
Article
Sézary syndrome is a cutaneous T-cell lymphoma characterized by erythroderma and leukemic involvement. We sought to define the clinical, biologic, and histopathologic features of Sézary syndrome without erythroderma. Features of patients with Sézary syndrome and normal-appearing skin or stage-T1 patches, fulfilling Sézary syndrome hematologic crite...
Article
CD160 is a GPI-anchored Ig-like receptor identified by the BY55 mAb on human circulating CD56dim+ NK cells and TCRγδ lymphocytes. In addition, while most intestinal T lymphocytes express it, only a minor circulating CD4+ or CD8+ T lymphocyte subset is CD160+. Here we describe a population of CD4+CD160+ human blood T lymphocytes of circulating cutan...
Article
Full-text available
Cutaneous wound healing requires keratinocyte proliferation, migration and differentiation to restore the barrier function of the skin. The calcineurin/nuclear factor of activated-T-cell (NFAT) signaling pathway has been recently shown to be involved in keratinocyte growth, differentiation and migration. It is induced by an increased intracellular...
Article
Full-text available
The diverse aspects of Cutaneous T-cell lymphomas may impede the diagnosis of Sézary syndrome (SS) and mycosis fungoides (MF), in particular at early stages of the disease. We defined the CD158k/KIR3DL2 molecule as a first positive cell surface marker for Sézary cells (SCs). Here, we designed an optimized flow-cytometry gating strategy, allowing th...
Article
Array Comparative Genomic Hybridization (aCGH) has progressively replaced conventional karyotype in the diagnostic strategy of intellectual disability (ID) and congenital malformations. This technique increases the diagnostic rate but also the possibility of finding unexpected variants unrelated to the indication of referral, namely incidental find...
Article
Alemtuzumab has been proposed as salvage therapy for refractory cutaneous T-cell lymphomas (CTCL). Long-term follow-up data are scarce. To assess the efficacy and safety of alemtuzumab in the treatment of advanced CTCL. Multicenter retrospective analysis of 39 patients with advanced CTCL treated with alemtuzumab between 2003 and 2013. Thirty-nine p...