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BACKGROUND: The contribution of Staphylococcus aureus to the exacerbation of atopic dermatitis (AD) is widely documented, but its role as a primary trigger of AD skin symptoms remains poorly explored. OBJECTIVES: This study sought to reappraise the main bacterial factors and underlying immune mechanisms by which S aureus triggers AD-like inflammation. METHODS: This study capitalized on a preclinical model, in which different clinical isolates were applied in the absence of any prior experimental skin injury. RESULTS: The development of S aureus-induced dermatitis depended on the nature of the S aureus strain, its viability, the concentration of the applied bacterial suspension, the production of secreted and nonsecreted factors, as well as the activation of accessory gene regulatory quorum sensing system. In addition, the rising dermatitis, which exhibited the well-documented AD cytokine signature, was significantly inhibited in inflammasome adaptor apoptosis-associated speck-like protein containing a CARD domain- and monocyte/macrophage-deficient animals, but not in T- and B-cell-deficient mice, suggesting a major role for the innate response in the induction of skin inflammation. However, bacterial exposure generated a robust adaptive immune response against S aureus, and an accumulation of S aureus-specific γδ and CD4+ tissue resident memory T cells at the site of previous dermatitis. The latter both contributed to worsen the flares of AD-like dermatitis on new bacteria exposures, but also, protected the mice from persistent bacterial colonization. CONCLUSIONS: These data highlight the induction of unique AD-like inflammation, with the generation of proinflammatory but protective tissue resident memory T cells in a context of natural exposure to pathogenic S aureus strains.
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Dermatitis Atópica , Células T de Memoria , Piel , Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Dermatitis Atópica/inmunología , Dermatitis Atópica/microbiología , Staphylococcus aureus/inmunología , Ratones , Piel/inmunología , Piel/microbiología , Piel/patología , Infecciones Estafilocócicas/inmunología , Células T de Memoria/inmunología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Femenino , Citocinas/metabolismo , Citocinas/inmunología , Brote de los Síntomas , Infecciones Cutáneas Estafilocócicas/inmunología , Infecciones Cutáneas Estafilocócicas/microbiologíaRESUMEN
BACKGROUND: We evaluated co-administration of adjuvanted seasonal quadrivalent influenza vaccine (FLU-aQIV) and respiratory syncytial virus (RSV) prefusion F protein-based vaccine (RSVPreF3 OA) in ≥65-year-olds. METHODS: This phase 3, open-label trial randomized ≥65-year-olds to receive FLU-aQIV and RSVPreF3 OA concomitantly (Co-Ad) or sequentially, 1 month apart (Control). Primary objectives were to demonstrate the non-inferiority of FLU-aQIV and RSVPreF3 OA co-administration versus sequential administration in terms of hemagglutination inhibition (HI) titers for each FLU-aQIV strain and RSV-A and RSV-B neutralization titers, 1 month post-vaccination. Reactogenicity and safety were also assessed. RESULTS: Overall, 1045 participants were vaccinated (Co-Ad: 523; Control: 522). Non-inferiority of FLU-aQIV and RSVPreF3 OA co-administration versus sequential administration was demonstrated in terms of HI titers for the A/Victoria(H1N1), B/Victoria, and B/Yamagata influenza strains and RSV-A neutralization titers (upper limits [ULs] of 95% confidence intervals [CIs] for adjusted geometric mean titer [GMT] ratios [Control/Co-Ad] ≤1.50) but not for A/Darwin(H3N2) HI titers (95% CI UL = 1.53). The immune response to A/Darwin(H3N2) was further assessed post-hoc using a microneutralization assay; the post-vaccination adjusted GMT ratio (Control/Co-Ad) was 1.23 (95% CI: 1.06-1.42, ie, UL ≤1.50), suggesting an adequate immune response to A/Darwin(H3N2) following co-administration. RSV-B neutralization titers were comparable between groups (95% CI UL for adjusted GMT ratio ≤1.50). Solicited adverse events were mostly mild or moderate and transient; unsolicited and serious adverse event rates were balanced between groups. CONCLUSIONS: Adjuvanted FLU-aQIV and RSVPreF3 OA had acceptable reactogenicity/safety profiles when co-administered in ≥65-year-olds, without clinically relevant interference with the immune responses to either vaccine. CLINICAL TRIALS REGISTRATION: NCT05568797.
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BACKGROUND: Tissue-resident memory T (TRM ) cells are detrimental in allergic contact dermatitis (ACD), in which they contribute to the chronicity and severity of the disease. METHODS: We assessed the impact of a standard topical corticosteroid (TCS) treatment, triamcinolone acetonide (TA), on the formation, maintenance and reactivation of epidermal TRM cells in a preclinical model of ACD to 2,4-dinitrofluorobenzene. TA 0.01% was applied at different time points of ACD response and we monitored skin inflammation and tracked CD8+ CD69+ CD103+ TRM by flow cytometry and RNA sequencing. RESULTS: The impact of TA on TRM formation depended on treatment regimen: (i) in a preventive mode, that is, in sensitized mice before challenge, TA transiently inhibited the infiltration of effector T cells and the accumulation of TRM upon hapten challenge. In contrast, (ii) in a curative mode, that is, at the peak of the ACD response, TA blocked skin inflammation but failed to prevent the formation of TRM . Finally, (iii) in a proactive mode, that is, on previous eczema lesions, TA had no effect on the survival of skin TRM , but transiently inhibited their reactivation program upon allergen reexposure. Indeed, specific TRM progressively regained proliferative functions upon TA discontinuation and expanded in the tissue, leading to exaggerated iterative responses. Interestingly, TRM re-expansion correlated with the decreased clearance of hapten moieties from the skin induced by repeated TA applications. CONCLUSIONS: Our results demonstrate that TCS successfully treat ACD inflammation, but are mostly ineffective in impeding the formation and expansion of allergen-specific TRM , which certainly restricts the induction of lasting tolerance in patients with chronic dermatitis.
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Dermatitis Alérgica por Contacto , Dermatitis Atópica , Fármacos Dermatológicos , Humanos , Ratones , Animales , Células T de Memoria , Linfocitos T CD8-positivos , Piel/patología , Dermatitis Alérgica por Contacto/tratamiento farmacológico , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/patología , Alérgenos , Inflamación/tratamiento farmacológico , Inflamación/patología , Haptenos , Corticoesteroides , Memoria InmunológicaRESUMEN
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) represent a severe spectrum of rare mucocutaneous reactions, primarily drug-induced and characterized by significant morbidity and mortality. These conditions manifest through extensive skin detachment, distinguishing them from other generalized skin eruptions. The rarity and severity of SJS/TEN underscore the importance of accurate diagnostic criteria and effective treatments, which are currently lacking consensus. This review proposes new diagnostic criteria to improve specificity and global applicability. Recent advancements in understanding the immunopathogenesis of SJS/TEN are explored, emphasizing the role of drug-specific T cell responses and HLA polymorphisms in disease onset. The review also addresses current therapeutic approaches, including controversies surrounding the use of immunosuppressive agents and the emerging role of TNF-α inhibitors. Novel therapeutic strategies targeting specific pathogenic mechanisms, such as necroptosis and specific immune cell pathways, are discussed. Furthermore, the development of new drugs based on these insights, including targeted monoclonal antibodies and inhibitors, are examined. The review concludes by advocating for more robust and coordinated efforts across multidisciplinary medical fields to develop effective treatments and diagnostic tools for SJS/TEN, with the aim of improving patient outcomes and understanding of the disease and its mechanisms.
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BACKGROUND: Distinguishing between allergic and nonallergic forms of Contact Dermatitis (CD) is challenging and requires investigations based on patch-testing. Early detection of allergy biomarkers in active CD lesions could refine and simplify the management of CD patients. OBJECTIVE: To characterize the molecular signatures of active CD lesions. METHODS: We studied the expression of 12 allergy biomarkers by qRT-PCR in active lesions of 38 CD patients. Allergic CD (ACD) was diagnosed based on patch test (PT) results and exposure assessment. Molecular signatures of active lesions, as well as positive PT reactions, were compared with those of reference chemical allergens and irritants. RESULTS: Nineteen of the 38 CD patients reacted positively upon patch-testing and exposure assessment confirmed ACD diagnosis for 17 of them. Gene profiling of active CD lesions revealed 2 distinct molecular patterns: patients harboring signatures similar to reference allergens (n = 23) or irritants (n = 15). Among the 23 patients with an "allergy signature," we found the 17 patients with confirmed ACD, while no culprit allergen was identified for the 6 other patients. Interestingly, the 15 patients without biomarker induction had negative PT, suggesting that they developed nonallergic CD reactions. CONCLUSION: Molecular signatures from active skin lesions may help to stratify CD patients and predict those suffering from ACD.
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Dermatitis Alérgica por Contacto , Dermatitis Irritante , Humanos , Irritantes , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/genética , Dermatitis Alérgica por Contacto/patología , Alérgenos , Pruebas del Parche/métodos , Biomarcadores , Dermatitis Irritante/diagnósticoRESUMEN
INTRODUCTION: Atopic dermatitis (AD), a chronic type 2 inflammatory skin disease, is frequently associated with ocular surface diseases (OSD) which may appear or worsen under anti-type 2-targeted treatments. However, the exact prevalence of OSD and the ophthalmology referral criteria remain ill-defined in AD patients before initiating such biotherapies. We aimed to characterize the prevalence, the nature and the factors related to OSD development in AD that may justify an ophthalmological management. METHODS: A total of 98 consecutive AD inpatients without biological treatment were retrospectively included. These were systematically evaluated by an ophthalmologist during their dermatological care. Clinical and laboratory data were analysed to characterize OSD and their risk factors. RESULTS: OSD were found in 83/98 AD patients (85%); mainly dry eye syndrome (64%, 63/98), allergic conjunctivitis (42%, 41/98), posterior (33%, 32/98), and anterior blepharitis (27%, 26/98). In AD patients without ocular symptoms, OSDs were also frequently found (63%, 12/19) and were mostly mild. Risk factors for OSD were history of allergic rhinitis, allergic sensitization, head and neck AD, ocular symptoms (foreign body sensation in the eye, burning, itching, photophobia), and total IgE level >3,000 kU/L. CONCLUSION: The prevalence of OSD was high, even in asymptomatic patients. The risk factors identified may indicate the need for ophthalmological examination for therapeutic management, especially when biological agents targeting type 2 inflammation are considered.
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Dermatitis Atópica , Humanos , Dermatitis Atópica/complicaciones , Dermatitis Atópica/epidemiología , Masculino , Femenino , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Síndromes de Ojo Seco/epidemiología , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/diagnóstico , Conjuntivitis Alérgica/epidemiología , Conjuntivitis Alérgica/complicaciones , Adulto Joven , Blefaritis/epidemiología , Blefaritis/etiología , Adolescente , Anciano , Oftalmopatías/epidemiología , Oftalmopatías/etiologíaRESUMEN
BACKGROUND: Epicutaneous immunotherapy (EPIT) protocols have recently been developed to restore tolerance in patients with food allergy. The mechanisms by which EPIT protocols promote desensitization rely on a profound immune deviation of pathogenic T- and B-cell responses. OBJECTIVE: To date, little is known about the contribution of skin dendritic cells (skDCs) to T-cell remodeling and EPIT efficacy. METHODS: We capitalized on a preclinical model of food allergy to ovalbumin (OVA) to characterize the phenotype and functions of OVA+ skDCs throughout the course of EPIT. RESULTS: Our results showed that both Langerhans cells and dermal conventional cDC1 and cDC2 subsets retained their ability to capture OVA in the skin and to migrate toward the skin-draining lymph nodes during EPIT. However, their activation/maturation status was significantly impaired, as evidenced by the gradual and selective reduction of CD86, CD40, and OVA protein expression in respective subsets. Phenotypic changes during EPIT were also characterized by a progressive diversification of single-cell gene signatures within each DC subset. Interestingly, we observed that OVA+ Langerhans cells progressively lost their capacity to prime CD4+ TEFF cells, but gained regulatory T-cell stimulatory properties. In contrast, cDC1 were inefficient in priming CD4+ TEFF cells or in reactivating TMEM cells in vitro, whereas cDC2 retained moderate stimulatory properties, and progressively biased type 2 immunity toward type 1 and type 17 responses. CONCLUSIONS: Our results therefore emphasize that the acquisition of distinct phenotypic and functional specializations by skDCs during EPIT is at the cornerstone of the desensitization process.
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Hipersensibilidad a los Alimentos , Células de Langerhans , Humanos , Desensibilización Inmunológica/métodos , Ovalbúmina , Linfocitos T Reguladores , AlérgenosRESUMEN
BACKGROUND: Cancer patients are being exposed to antineoplastic drugs more frequently and for longer periods, resulting in a higher risk of hypersensitivity reactions. The aim of this study was to assess the pharmaceutical time and direct cost of drug allergy explorations following immediate hypersensitivity reactions to antineoplastic agents. METHODS: A micro-costing method was used to collect data on consumption of human and material resources for allergy exploration preparations. The monetisation was carried out on the basis of prices and hourly wage costs applied in 2018. The number and type of allergy explorations prepared by the pharmacy as well as nature of antineoplastic drugs tested, and the number of culprit drugs reintroductions were collected. RESULTS: Almost 1.5â h is required to realise allergy tests for one patient including pharmacist time for prescription analysis and pharmacy technician's time for tests preparation. The mean manufacturing cost of these tests is estimated at 62.87 (57.82-65.49) per culprit drug for one patient. Programming patients according to culprit drugs tested allows rationalising healthcare provider time and increasing efficiency. From January 2010 to December 2018, 277 patients were tested and 490 allergy explorations were performed, corresponding to more than 5000 preparations. Mostly, the culprit drug could be reintroduced (n = 383, 78.2%) allowing patients to receive the best possible treatment. CONCLUSION: Management of hypersensitivity reactions is constantly progressing, as it contributes to improving patient care in oncology. This activity is time-consuming for the pharmacy team but allows patients with previous hypersensitivity reaction to continue effective treatment.
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Antineoplásicos , Hipersensibilidad a las Drogas , Hipersensibilidad Inmediata , Farmacia , Antineoplásicos/efectos adversos , Hipersensibilidad a las Drogas/etiología , Hipersensibilidad a las Drogas/terapia , Humanos , Hipersensibilidad Inmediata/inducido químicamente , Pruebas CutáneasRESUMEN
BACKGROUND: Diagnosis of contact allergy (CA) to Amerchol L-101 (AL-101), a marker for lanolin allergy, is problematic. Positive patch test reactions are frequently doubtful or weakly positive and difficult to associate with clinical relevance. OBJECTIVE: To gain further insight on the allergic or irritant nature of skin reactions induced by AL-101 patch test. METHODS: We re-tested in a dose-response fashion, 10 subjects with AL-101 CA and performed comprehensive transcriptomic analysis (gene arrays, quantitative real-time polymerase chain reaction [qRT-PCR]) of samples of their skin reactions. RESULTS: Eight of the 10 CA subjects reacted positively upon re-test, whereas two did not react. Most of AL-101 positive patch tests expressed an allergy signature with strong activation of gene modules associated with adaptive immunity and downregulation of cornification pathway genes. In addition, the breadth of gene modulation correlated with the magnitude of patch test reactions and the concentration of AL-101 applied. However, we observed that some of the positive patch test reactions to AL-101 expressed no/few allergy biomarkers, suggesting the induction of an irritant skin inflammation in these samples. CONCLUSIONS: This study confirms that AL-101 is an allergen that can cause both contact allergy and contact irritation. Our results also highlight that molecular profiling might help to strengthen clinical diagnosis.
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Dermatitis Alérgica por Contacto , Alérgenos/efectos adversos , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/genética , Humanos , Irritantes/efectos adversos , Lanolina , Pruebas del Parche/métodosRESUMEN
Extracorporeal photochemotherapy (ECP) that takes advantage of the immunomodulatory effects of UV light has been extensively used for many years for the treatment of several T cell-mediated diseases, including graft-versus-host disease (GvHD) and systemic scleroderma. Immune mechanisms that lead to the establishment of T cell tolerance in ECP-treated patients remain poorly known. In this study, we have tested the effect of UV/psoralen-treated BM-derived dendritic cells, referred to as ECP-BMDCs on the outcome of an antigen-specific T cell-mediated reaction, that is, contact hypersensitivity (CHS), which is mediated by CD8+ effector T cells (CD8+ Teff ). The intravenous (i.v.) injection of antigen-pulsed ECP-BMDCs in recipient C57BL/6 mice induced specific CD8+ T cells endowed with immunomodulatory properties (referred to as CD8+ TECP ), which prevented the priming of CD8+ Teff and the development of CHS, independently of conventional CD4+ regulatory T cells. CD8+ TECP mediated tolerance by inhibiting the migration and functions of skin DC and subsequently the priming of CD8+ Teff . CD8+ TECP displayed none of the phenotypes of the usual CD8+ T regulatory cells described so far. Our results reveal an underestimated participation of CD8+ T cells to ECP-induced immunomodulation that could explain the therapeutic effects of ECP in T cell-mediated diseases.
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Células Dendríticas/inmunología , Dermatitis por Contacto/terapia , Tolerancia Inmunológica , Inmunomodulación/efectos de la radiación , Linfocitos T Citotóxicos/efectos de la radiación , Linfocitos T Reguladores/efectos de la radiación , Alérgenos/administración & dosificación , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/inmunología , Células Dendríticas/citología , Células Dendríticas/trasplante , Dermatitis por Contacto/inmunología , Dermatitis por Contacto/fisiopatología , Dinitrofluorobenceno/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Ficusina/administración & dosificación , Humanos , Ratones Endogámicos C57BL , Ratones Transgénicos , Fotoféresis/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/patología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología , Rayos UltravioletaRESUMEN
BACKGROUND: Skin exposure to chemicals may induce an inflammatory disease known as contact dermatitis (CD). Distinguishing the allergic and irritant forms of CD often proves challenging in the clinic. METHODS: To characterize the molecular signatures of chemical-induced skin inflammation, we conducted a comprehensive transcriptomic analysis on the skin lesions of 47 patients with positive patch tests to reference contact allergens and nonallergenic irritants. RESULTS: A clear segregation was observed between allergen- and irritant-induced gene profiles. Distinct modules pertaining to the epidermal compartment, metabolism, and proliferation were induced by both contact allergens and irritants; whereas only contact allergens prompted strong activation of adaptive immunity, notably of cytotoxic T-cell responses. Our results also confirmed that: (a) unique pathways characterize allergen- and irritant-induced dermatitis; (b) the intensity of the clinical reaction correlates with the magnitude of immune activation. Finally, using a machine-learning approach, we identified and validated several minimal combinations of biomarkers to distinguish contact allergy from irritation. CONCLUSION: These results highlight the value of molecular profiling of chemical-induced skin inflammation for improving the diagnosis of allergic versus irritant contact dermatitis.
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Dermatitis Alérgica por Contacto , Dermatitis Irritante , Alérgenos , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/etiología , Dermatitis Irritante/etiología , Dermatitis Irritante/genética , Humanos , Inflamación , Irritantes/efectos adversos , Pruebas del ParcheRESUMEN
Cystic fibrosis (CF) patients receive many antibiotic treatments for recurrent respiratory infections and frequently report antibiotic hypersensitivity reactions (HSRs). In this retrospective study, medical records of CF patients were reviewed to clarify the clinical features, the culprit antibiotics, and the prevalence of antibiotic HSRs in the CF population. From 601 CF patients, 95 suspected antibiotic HSRs occurred in 60 patients (prevalence of 10.0%). ß-Lactams were the most common inducers, but cotrimoxazole was also frequently involved. Seventy-six of 95 suspected HSRs were assessed by allergy workup including skin tests (43/76 reactions) and/or drug reintroduction as a full course of the culprit antibiotic (73 of 76 reactions). From the 43 suspected HSRs that were skin-tested, only three had positive skin tests and were not subjected to drug readministration. All the other 73 suspected HSRs received a full course of the culprit antibiotic: HSR symptoms recurred in 10 of 73 cases and therefore were considered as confirmed antibiotic HSRs; for the remaining 63 suspected HSRs that did not relapse after drug readministration, the diagnosis of antibiotic HSRs was excluded. In summary, 13 of 76 suspected HSRs were confirmed as antibiotic HSRs. The prevalence of suspected and confirmed antibiotic HSRs in CF patients appears similar to that reported in the general population. Of note, most of the antibiotic suspected HSRs are not confirmed after allergology workup. A complete allergy workup appears therefore crucial to make a correct diagnosis and to avoid unnecessary contraindication of major antibiotics.
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Antibacterianos/efectos adversos , Fibrosis Quística/tratamiento farmacológico , Hipersensibilidad a las Drogas/diagnóstico , Adolescente , Adulto , Antibacterianos/uso terapéutico , Niño , Fibrosis Quística/epidemiología , Fibrosis Quística/inmunología , Hipersensibilidad a las Drogas/epidemiología , Hipersensibilidad a las Drogas/etiología , Femenino , Humanos , Masculino , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Pruebas Cutáneas , Adulto Joven , beta-Lactamas/efectos adversos , beta-Lactamas/uso terapéuticoRESUMEN
BACKGROUND: Tissue-resident memory T (Trm) cells are detrimental in patients with numerous chronic inflammatory diseases, including allergic contact dermatitis (ACD). OBJECTIVES: We sought to analyze the contribution of Trm cells to the chronicity and severity of ACD and to define the local parameters regulating their development and functions. METHODS: We used an experimental model of ACD (ie, contact hypersensitivity to 2,4-dinitrofluorobenzene) that is mediated by CD8+ T cells. RESULTS: Our data show that early effector T cells accumulated in the skin during the acute contact hypersensitivity reaction and gave rise to epidermal CD8+ Trm cells expressing a specific set of inhibitory checkpoint receptors (ICRs), such as programmed cell death protein 1 (PD-1) and T cell immunoglobulin and mucin domain 3 (TIM-3). Those Trm cells remained in the epidermis for several weeks and mediated the eczema exacerbations, which developed on allergen re-exposure without the contribution of circulating specific T cells. Furthermore, allergen-induced Trm cell reactivation was constrained because treatment with ICR antagonists dramatically enhanced the magnitude and severity of eczema exacerbations. Finally, we show that the persistence of the allergen in the epidermis for long periods of time was responsible for both the development and maintenance of epidermal Trm cells, as well as the sustained expression of ICRs. CONCLUSION: Although CD8+ Trm cells are key for the pathophysiology of ACD, intrinsic mechanisms control their reactivation to prevent damaging immunopathology. Developing strategies targeting the reactivation of skin Trm cells in situ through their ICRs should open new perspectives for the treatment of ACD.
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Linfocitos T CD8-positivos/inmunología , Dermatitis Alérgica por Contacto/inmunología , Receptor 2 Celular del Virus de la Hepatitis A/inmunología , Memoria Inmunológica , Receptor de Muerte Celular Programada 1/inmunología , Piel/inmunología , Alérgenos , Animales , Células Cultivadas , Dinitrofluorobenceno , Femenino , Ratones Endogámicos C57BL , Oxazolona , Índice de Severidad de la EnfermedadRESUMEN
Posterior body elongation is a widespread mechanism propelling the generation of the metazoan body plan. The posterior growth model predicts that a posterior growth zone generates sufficient tissue volume to elongate the posterior body. However, there are energy supply-related differences between vertebrates in the degree to which growth occurs concomitantly with embryogenesis. By applying a multi-scalar morphometric analysis in zebrafish embryos, we show that posterior body elongation is generated by an influx of cells from lateral regions, by convergence-extension of cells as they exit the tailbud, and finally by a late volumetric growth in the spinal cord and notochord. Importantly, the unsegmented region does not generate additional tissue volume. Fibroblast growth factor inhibition blocks tissue convergence rather than volumetric growth, showing that a conserved molecular mechanism can control convergent morphogenesis through different cell behaviours. Finally, via a comparative morphometric analysis in lamprey, dogfish, zebrafish and mouse, we propose that elongation via posterior volumetric growth is linked to increased energy supply and is associated with an overall increase in volumetric growth and elongation.
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Tipificación del Cuerpo , Organogénesis , Vertebrados/embriología , Animales , Movimiento Celular , Proliferación Celular , Cazón/embriología , Factores de Crecimiento de Fibroblastos/metabolismo , Lampreas/embriología , Ratones , Notocorda/embriología , Transducción de Señal , Especificidad de la Especie , Médula Espinal/embriología , Cola (estructura animal) , Pez Cebra/embriologíaRESUMEN
This paper summarizes and reviews the mechanisms of action and data concerning efficacy of recommended treatments as well as other treatments that have been tested, independently of the outcomes, in the management of chronic spontaneous urticaria. Due to the central role of mast cells, basophils and histamine in the pathophysiology of this disease, H1-antihistamines remain the first-line treatment. However, current knowledge about this complex disease, also recognizes an important role for T lymphocytes, B lymphocytes, and autoantibodies. Implications of these others mediators thus provide further targets for treatment. Indeed, agents previously used to treat other autoimmune and inflammatory diseases, have demonstrated efficacy in chronic spontaneous urticaria and are therefore potential therapeutic alternatives for antihistamine unresponsive patients.
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Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Mastocitos/efectos de los fármacos , Urticaria/tratamiento farmacológico , Autoanticuerpos/efectos de los fármacos , Autoanticuerpos/inmunología , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Basófilos/efectos de los fármacos , Basófilos/inmunología , Enfermedad Crónica , Antagonistas de los Receptores Histamínicos H1/inmunología , Humanos , Mastocitos/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Urticaria/inmunología , Urticaria/patologíaRESUMEN
Atopic dermatitis (AD) is a common skin inflammatory disease characterized by the production of thymic stromal lymphopoietin (TSLP) and marked TH 2 polarization. Recent studies suggest that IL-1ß contributes to the development of AD skin inflammation. Here, we have investigated the impact of IL-1ß signalling on the epidermal homeostasis of both healthy subjects and AD patients [with functional filaggrin (FLG) alleles], with particular attention to TSLP production and keratinocyte differentiation. In healthy reconstructed human epidermis (RHE), IL-1ß promoted (i) robust secretion of TSLP in an NF-κB-dependent manner and (ii) a significant decrease in the expression of filaggrin and other proteins of the epidermal differentiation complex. These effects were prevented by treatment of RHE with the anti-IL-1ß mAb canakinumab and by the IL-1 receptor antagonist anakinra. Interestingly, RHE generated from AD donors behaved like that of healthy individuals and showed comparable responses to IL-1ß signals. Collectively, our results suggest that IL-1ß may be an early key mediator for the acquisition of an AD phenotype through induction of TSLP and alteration of the epidermal homeostasis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Citocinas/genética , Dermatitis Atópica/genética , Interleucina-1beta/genética , Adulto , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Diferenciación Celular , Citocinas/metabolismo , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/metabolismo , Dermatitis Atópica/patología , Epidermis/metabolismo , Epidermis/patología , Femenino , Proteínas Filagrina , Homeostasis , Humanos , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Interleucina-1beta/metabolismo , Proteínas de Filamentos Intermediarios/genética , Proteínas de Filamentos Intermediarios/metabolismo , Masculino , Persona de Mediana Edad , FN-kappa B/genética , FN-kappa B/metabolismo , Fenotipo , Adulto Joven , Linfopoyetina del Estroma TímicoAsunto(s)
Hipersensibilidad a las Drogas/inmunología , Hipersensibilidad Tardía/inmunología , Mastocitos/inmunología , Linfocitos T Citotóxicos/inmunología , Urticaria/inmunología , Animales , Degranulación de la Célula , Humanos , Proteínas del Tejido Nervioso/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropéptido/metabolismo , Xenobióticos/efectos adversosRESUMEN
The hair follicle (HF) is a multi-tissue mini-organ that self-renews periodically. However, the cellular organisation of this much-studied model is not fully understood. The structures of the outer layer and of the bulb, which ensures HF growth, have not been completely established. To clarify these points, we have conducted in vivo clonal analyses with 3D imaging in mice. The upper two-thirds of the HF outer layer consists of two clonally unrelated groups of cells that exhibit different modes of growth. They correspond to the basal outer root sheath (ORS) and the companion layer (Cp). The basal ORS has an unusual anisotropic mode of growth from a suprabulbar zone, which we named the privileged proliferation zone. The Cp has a stem/transient-amplifying mode of growth and is shown to be an HF internal structure. Furthermore, we describe an additional element, the bulb outer layer, which is contiguous and shares markers (e.g. Lgr5) with the basal ORS but is formed by a separate lineage that belongs neither to the ORS nor Cp lineage. It represents a novel element with proximal cells that are contiguous with the germinative layer in the bulb. In reference to its shape and position we named it the lower proximal cup (LPC). These clonal hierarchies reveal a novel model of HF organisation and growth based on two major entities: the basal ORS and the LPC plus the seven internal layers.