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1.
Trends Biochem Sci ; 49(3): 257-276, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38233282

RESUMEN

Histone lysine demethylases (KDMs) regulate eukaryotic gene transcription by catalysing the removal of methyl groups from histone proteins. These enzymes are intricately regulated by the kinase signalling system in response to internal and external stimuli. Here, we review the mechanisms by which kinase-mediated phosphorylation influence human histone KDM function. These include the changing of histone KDM subcellular localisation or chromatin binding, the altering of protein half-life, changes to histone KDM complex formation that result in histone demethylation, non-histone demethylation or demethylase-independent effects, and effects on histone KDM complex dissociation. We also explore the structural context of phospho-sites on histone KDMs and evaluate how this relates to function.


Asunto(s)
Histona Demetilasas , Histonas , Humanos , Histona Demetilasas/metabolismo , Histonas/metabolismo , Histona Demetilasas con Dominio de Jumonji/química , Histona Demetilasas con Dominio de Jumonji/genética , Histona Demetilasas con Dominio de Jumonji/metabolismo , Fosforilación , Desmetilación
2.
N Engl J Med ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38804512

RESUMEN

BACKGROUND: Minimal change disease and primary focal segmental glomerulosclerosis in adults, along with idiopathic nephrotic syndrome in children, are immune-mediated podocytopathies that lead to nephrotic syndrome. Autoantibodies targeting nephrin have been found in patients with minimal change disease, but their clinical and pathophysiological roles are unclear. METHODS: We conducted a multicenter study to analyze antinephrin autoantibodies in adults with glomerular diseases, including minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, IgA nephropathy, antineutrophil cytoplasmic antibody-associated glomerulonephritis, and lupus nephritis, as well as in children with idiopathic nephrotic syndrome and in controls. We also created an experimental mouse model through active immunization with recombinant murine nephrin. RESULTS: The study included 539 patients (357 adults and 182 children) and 117 controls. Among the adults, antinephrin autoantibodies were found in 46 of the 105 patients (44%) with minimal change disease, 7 of 74 (9%) with primary focal segmental glomerulosclerosis, and only in rare cases among the patients with other conditions. Of the 182 children with idiopathic nephrotic syndrome, 94 (52%) had detectable antinephrin autoantibodies. In the subgroup of patients with active minimal change disease or idiopathic nephrotic syndrome who were not receiving immunosuppressive treatment, the prevalence of antinephrin autoantibodies was as high as 69% and 90%, respectively. At study inclusion and during follow-up, antinephrin autoantibody levels were correlated with disease activity. Experimental immunization induced a nephrotic syndrome, a minimal change disease-like phenotype, IgG localization to the podocyte slit diaphragm, nephrin phosphorylation, and severe cytoskeletal changes in mice. CONCLUSIONS: In this study, circulating antinephrin autoantibodies were common in patients with minimal change disease or idiopathic nephrotic syndrome and appeared to be markers of disease activity. Their binding at the slit diaphragm induced podocyte dysfunction and nephrotic syndrome, which highlights their pathophysiological significance. (Funded by Deutsche Forschungsgemeinschaft and others.).

3.
Immunol Rev ; 320(1): 29-57, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37283511

RESUMEN

The structurally and functionally related interleukin-4 (IL-4) and IL-13 cytokines play pivotal roles in shaping immune activity. The IL-4/IL-13 axis is best known for its critical role in T helper 2 (Th2) cell-mediated Type 2 inflammation, which protects the host from large multicellular pathogens, such as parasitic helminth worms, and regulates immune responses to allergens. In addition, IL-4 and IL-13 stimulate a wide range of innate and adaptive immune cells, as well as non-hematopoietic cells, to coordinate various functions, including immune regulation, antibody production, and fibrosis. Due to its importance for a broad spectrum of physiological activities, the IL-4/IL-13 network has been targeted through a variety of molecular engineering and synthetic biology approaches to modulate immune behavior and develop novel therapeutics. Here, we review ongoing efforts to manipulate the IL-4/IL-13 axis, including cytokine engineering strategies, formulation of fusion proteins, antagonist development, cell engineering approaches, and biosensor design. We discuss how these strategies have been employed to dissect IL-4 and IL-13 pathways, as well as to discover new immunotherapies targeting allergy, autoimmune diseases, and cancer. Looking ahead, emerging bioengineering tools promise to continue advancing fundamental understanding of IL-4/IL-13 biology and enabling researchers to exploit these insights to develop effective interventions.


Asunto(s)
Interleucina-13 , Interleucina-4 , Humanos , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Citocinas/metabolismo , Células Th2 , Inmunidad
4.
Nat Chem Biol ; 19(9): 1127-1137, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37024727

RESUMEN

The interleukin-4 (IL-4) cytokine plays a critical role in modulating immune homeostasis. Although there is great interest in harnessing this cytokine as a therapeutic in natural or engineered formats, the clinical potential of native IL-4 is limited by its instability and pleiotropic actions. Here, we design IL-4 cytokine mimetics (denoted Neo-4) based on a de novo engineered IL-2 mimetic scaffold and demonstrate that these cytokines can recapitulate physiological functions of IL-4 in cellular and animal models. In contrast with natural IL-4, Neo-4 is hyperstable and signals exclusively through the type I IL-4 receptor complex, providing previously inaccessible insights into differential IL-4 signaling through type I versus type II receptors. Because of their hyperstability, our computationally designed mimetics can directly incorporate into sophisticated biomaterials that require heat processing, such as three-dimensional-printed scaffolds. Neo-4 should be broadly useful for interrogating IL-4 biology, and the design workflow will inform targeted cytokine therapeutic development.


Asunto(s)
Citocinas , Interleucina-4 , Animales , Transducción de Señal
5.
PLoS Comput Biol ; 20(6): e1012123, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38935611

RESUMEN

AlphaFold2 is an Artificial Intelligence-based program developed to predict the 3D structure of proteins given only their amino acid sequence at atomic resolution. Due to the accuracy and efficiency at which AlphaFold2 can generate 3D structure predictions and its widespread adoption into various aspects of biochemical research, the technique of protein structure prediction should be considered for incorporation into the undergraduate biochemistry curriculum. A module for introducing AlphaFold2 into a senior-level biochemistry laboratory classroom was developed. The module's focus was to have students predict the structures of proteins from the MPOX 22 global outbreak virus isolate genome, which had no structures elucidated at that time. The goal of this study was to both determine the impact the module had on students and to develop a framework for introducing AlphaFold2 into the undergraduate curriculum so that instructors for biochemistry courses, regardless of their background in bioinformatics, could adapt the module into their classrooms.


Asunto(s)
Inteligencia Artificial , Bioquímica , Curriculum , Humanos , Bioquímica/educación , Biología Computacional/educación , Biología Computacional/métodos , Conformación Proteica , Estudiantes , Programas Informáticos , Universidades , Proteínas/química , Proteínas/metabolismo , Proteínas/genética , Secuencia de Aminoácidos
6.
Proc Natl Acad Sci U S A ; 119(13): e2200099119, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35324326

RESUMEN

SignificanceOscillations in intracellular calcium concentration play an essential role in the regulation of multiple cellular processes. In plants capable of root endosymbiosis with nitrogen-fixing bacteria and/or arbuscular mycorrhizal fungi, nuclear localized calcium oscillations are essential to transduce the microbial signal. Although the ion channels required to generate the nuclear localized calcium oscillations have been identified, their mechanisms of regulation are unknown. Here, we combined proteomics and engineering approaches to demonstrate that the calcium-bound form of the calmodulin 2 (CaM2) associates with CYCLIC NUCLEOTIDE GATED CHANNEL 15 (CNGC15s), closing the channels and providing the negative feedback to sustain the oscillatory mechanism. We further unraveled that the engineered CaM2 accelerates early endosymbioses and enhanced root nodule symbiosis but not arbuscular mycorrhization.


Asunto(s)
Fabaceae , Micorrizas , Calcio , Señalización del Calcio/fisiología , Micorrizas/fisiología , Simbiosis
7.
Horm Behav ; 162: 105544, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643533

RESUMEN

Essentially all neuropsychiatric diagnoses show some degree of sex and/or gender differences in their etiology, diagnosis, or prognosis. As a result, the roles of sex-related variables in behavior and cognition are of strong interest to many, with several lines of research showing effects on executive functions and value-based decision making in particular. These findings are often framed within a sex binary, with behavior of females described as less optimal than male "defaults"-- a framing that pits males and females against each other and deemphasizes the enormous overlap in fundamental neural mechanisms across sexes. Here, we propose an alternative framework in which sex-related factors encompass just one subset of many sources of valuable diversity in cognition. First, we review literature establishing multidimensional, nonbinary impacts of factors related to sex chromosomes and endocrine mechanisms on cognition, focusing on value- based decision-making tasks. Next, we present two suggestions for nonbinary interpretations and analyses of sex-related data that can be implemented by behavioral neuroscientists without devoting laboratory resources to delving into mechanisms underlying sex differences. We recommend (1) shifting interpretations of behavior away from performance metrics and towards strategy assessments to avoid the fallacy that the performance of one sex is worse than another; and (2) asking how much variance sex explains in measures and whether any differences are mosaic rather than binary, to avoid assuming that sex differences in separate measures are inextricably correlated. Nonbinary frameworks in research on cognition will allow neuroscience to represent the full spectrum of brains and behaviors.


Asunto(s)
Cognición , Toma de Decisiones , Animales , Femenino , Humanos , Masculino , Cognición/fisiología , Toma de Decisiones/fisiología , Cromosomas Sexuales/genética , Cromosomas Sexuales/fisiología , Factores Sexuales
8.
Gynecol Oncol ; 187: 221-226, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38821039

RESUMEN

OBJECTIVE: Due to limited data on homologous recombination deficiency (HRD) in older patients (≥ 70 years) with advanced stage high grade serous ovarian cancer (HGSC), we aimed to determine the rates of HRD at diagnosis in this age group. METHODS: From the Phase 3 trial VELIA the frequency of HRD and BRCA1/2 pathogenic variants (PVs) was compared between younger (< 70 years) and older participants. HRD and somatic(s) BRCA1/2 pathogenic variants (PVs) were determined at diagnosis using Myriad myChoice® CDx and germline(g) BRCA1/2 PVs using Myriad BRACAnalysis CDx®. HRD was defined if a BRCA PV was present, or the genomic instability score (GIS) met threshold (GIS ≥ 33 & ≥ 42 analyzed). RESULTS: Of 1140 participants, 21% were ≥ 70 years. In total, 26% (n = 298) had a BRCA1/2 PV and HRD, 29% (n = 329) were HRD/BRCA wild-type, 33% (n = 372) non-HRD, and 12% HR-status unknown (n = 141). HRD rates were higher in younger participants, 59% (n = 476/802), compared to 40% (n = 78/197) of older participants (GIS ≥ 42) [p < 0.001]; similar rates demonstrated with GIS ≥ 33, 66% vs 48% [p < 0.001]. gBRCA PVs observed in 24% younger vs 8% of older participants (p < 0.001); sBRCA in 8% vs 10% (p = 0.2559), and HRD (GIS ≥ 42) not due to gBRCA was 35% vs 31% (p = 0.36). CONCLUSIONS: HRD frequency was similar in participants aged < 70 and ≥ 70 years (35% vs 31%) when the contribution of gBRCA was excluded; rates of sBRCA PVs were also similar (8% v 10%), thus underscoring the importance of HRD and BRCA testing at diagnosis in older patients with advanced HGSC given the therapeutic implications.

9.
Arch Toxicol ; 98(2): 425-469, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38147116

RESUMEN

Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins. Alternariol (AOH), its monomethylether AME and the perylene quinones altertoxin I (ATX-I), ATX-II, ATX-III, alterperylenol (ALP), and stemphyltoxin III (STTX-III) showed in vitro genotoxic and mutagenic properties. Of all identified Alternaria toxins, the epoxide-bearing analogs ATX-II, ATX-III, and STTX-III show the highest cytotoxic, genotoxic, and mutagenic potential in vitro. Under hormone-sensitive conditions, AOH and AME act as moderate xenoestrogens, but in silico modeling predicts further Alternaria toxins as potential estrogenic factors. Recent studies indicate also an immunosuppressive role of AOH and ATX-II; however, no data are available for the majority of Alternaria toxins. Overall, hazard characterization of Alternaria toxins focused, so far, primarily on the commercially available dibenzo-α-pyrones AOH and AME and tenuazonic acid (TeA). Limited data sets are available for altersetin (ALS), altenuene (ALT), and tentoxin (TEN). The occurrence and toxicological relevance of perylene quinone-based Alternaria toxins still remain to be fully elucidated. We identified data gaps on hazard identification and characterization crucial to improve risk assessment of Alternaria mycotoxins for consumers and occupationally exposed workers.


Asunto(s)
Micotoxinas , Perileno , Humanos , Alternaria/metabolismo , Micotoxinas/toxicidad , Micotoxinas/análisis , Mutágenos/toxicidad , Mutágenos/metabolismo , Lactonas/toxicidad , Lactonas/metabolismo , Medición de Riesgo , Contaminación de Alimentos/análisis
10.
J Craniofac Surg ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738891

RESUMEN

Craniofacial microsomia (CFM) and microtia psychosocial research in the US is primarily with English-speaking participants. Given that 19% of the US is Latino, and there is a higher prevalence of CFM in Latino populations, this study aims to describe psychosocial experiences related to CFM among Spanish-speaking Latino caregivers to better inform health care. Narrative interviews (mean 73±17 min) were completed in Spanish with parents of children with CFM aged 3 to 17 (mean age 10.8±4.8 years). Transcripts were analyzed using quantitative linguistic analyses and reflexive thematic analysis. Participants (N=12) were mostly mothers (83%) who had immigrated to the US and had low socioeconomic status. Based upon analysis of grouped word counts, participants spent approximately half of their narratives discussing the first two years of their child's life. Themes selected based on US Latino sociodemographics and cultural values included the Impact of Language, Healthcare Challenges, Supportive Healthcare Experiences, Caregiver Coping with CFM, Family Roles, and Addressing Social Implications of CFM. Results highlighted that the first years of care are of critical importance to parents and suggest this is an optimal time to focus on education and support services for families. Additional treatment suggestions include providing interpretation and informational materials in Spanish, addressing care barriers, supporting familial and child coping, accounting for the role of extended family, and helping address social concerns. Ongoing research with Latino families can further assist in guiding culturally sensitive CFM health care.

11.
J Pediatr Nurs ; 77: e366-e374, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38729894

RESUMEN

PURPOSE: Craniofacial microsomia (CFM) is a congenital condition that can be associated with feeding challenges in infants. As part of the larger 'Craniofacial microsomia: Accelerating Research and Education (CARE)' program, this study described caregivers' early feeding experiences. DESIGN AND MATERIALS: US-based caregivers of 34 children with CFM participated in remote narrative interviews. Two authors completed inductive thematic analysis in an iterative process until consensus was reached. RESULTS: Caregivers' narratives outlined the inherent challenges of feeding an infant with special healthcare needs. The first theme 'Navigating Challenges and Managing Expectations' describes the distress participants experienced when they were unable to breastfeed and the negative emotional effect of switching to formula. The second theme 'Making Adaptations' outlines the methods participants tried, including breast pumps and feeding tubes. The third theme 'Accessing Support' describes participants' interactions with healthcare providers and challenges accessing feeding support. The final theme 'Growing from Adversity' recounts participants' relief once their child established a feeding pattern and the personal growth gained from their experiences. CONCLUSIONS: Caregivers reported several feeding related challenges associated with CFM, many of which negatively affected their wellbeing. Negative consequences were particularly pronounced in cases where caregivers' feeding experiences differed from their expectations. Participants identified challenges in accessing reliable feeding information and support. Despite difficult experiences, caregivers cited some positive outcomes, including increased confidence and resilience. PRACTICE IMPLICATIONS: Holistic feeding information and support for families affected by CFM should be inclusive of several feeding methods to improve care delivery, child health, and the caregiver experience.


Asunto(s)
Cuidadores , Humanos , Femenino , Masculino , Cuidadores/psicología , Lactante , Adulto , Síndrome de Goldenhar/enfermería , Lactancia Materna/psicología , Investigación Cualitativa , Estados Unidos , Preescolar , Adaptación Psicológica , Recién Nacido
12.
Cleft Palate Craniofac J ; : 10556656241241127, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38509820

RESUMEN

BACKGROUND: Individuals with cleft lip and/or palate (CL/P) may grow up with a visible facial difference, alongside speech and/or hearing challenges. Self-perceptions are stronger predictors of psychosocial adjustment than objective assessments, highlighting the importance of patient-reported outcome measures. Previously titled the Satisfaction with Appearance (SwA) questionnaire, the Cleft Hearing, Appearance and Speech Questionnaire (CHASQ) has been used in several countries to assess patient satisfaction, guide clinical decision-making, and conduct craniofacial research, but has lacked general population norms from which to draw comparisons. The aim of this study was to contribute to the development of norms by utilising existing data collected in the United Kingdom (UK) in 2004 using the original SwA. METHODS: SwA data collected from school pupils (n = 761) aged 10-16 years were analysed across age and gender. RESULTS: Hair, Eyes and Ears received the highest ratings, while Teeth received the lowest ratings. Those who were younger, and those who were male, generally rated their appearance more favourably. Thresholds are proposed to identify young people in need of clinical monitoring (10%) and intervention (5%). DISCUSSION: This study supports the potential of the CHASQ as a clinically useful outcome measure and research tool with the ability to identify appearance concerns in relation to specific facial features, as well as overall appearance satisfaction in young people with and without CL/P. Further validation of its use in the CL/P population and other patient groups, as well as countries outside the UK would add additional weight to the CHASQ's utility.

13.
Cleft Palate Craniofac J ; : 10556656241245284, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38584503

RESUMEN

OBJECTIVE: Children with craniofacial microsomia (CFM) have complex healthcare needs, resulting in evaluations and interventions from infancy onward. Yet, little is understood about families' treatment experiences or the impact of CFM on caregivers' well-being. To address this gap, the NIH-funded 'Craniofacial microsomia: Accelerating Research and Education (CARE)' program sought to develop a conceptual thematic framework of caregiver adjustment to CFM. DESIGN: Caregivers reported on their child's medical and surgical history. Narrative interviews were conducted with US caregivers (n = 62) of children aged 3-17 years with CFM. Transcripts were inductively coded and final themes and subthemes were identified. RESULTS: Components of the framework included: 1) Diagnostic Experiences, including pregnancy and birth, initial emotional responses, communication about the diagnosis by healthcare providers, and information-seeking behaviors; 2) Child Health and Healthcare Experiences, including feeding, the child's physical health, burden of care, medical decision-making, surgical experiences, and the perceived quality of care; 3) Child Development, including cognition and behavior, educational provision, social experiences, and emotional well-being; and 4) Family Functioning, including parental well-being, relationships, coping strategies, and personal growth. Participants also identified a series of "high" and "low" points throughout their journey and shared their priorities for future research. CONCLUSIONS: Narrative interviews provided rich insight into caregivers' experiences of having a child with CFM and enabled the development of a conceptual thematic framework to guide clinical care and future research. Information gathered from this study demonstrates the need to incorporate evidence-based psychological support for families into the CFM pathway from birth onward.

14.
Cleft Palate Craniofac J ; : 10556656241236580, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500357

RESUMEN

OBJECTIVE: Despite growing recognition that congenital craniofacial conditions have lifelong implications, psychological support for adults is currently lacking. The aim of this project was to produce a series of short films about living with craniosynostosis in adulthood, alongside a psychoeducational booklet. DESIGN: The resources were developed using multiple focus groups and meetings attended by researchers, patient representatives, a leading charitable organisation, an award-winning film production company, clinicians, and other experts in the field. RESULTS: An online mixed-methods survey was developed based on prior work to request feedback on the acceptability and utility of the resources from the craniosynostosis community. While data collection to evaluate the resources is ongoing, preliminary results (n = 36) highlight an acceptability rating of 100%. CONCLUSIONS: The resources developed represent a step forward in addressing the unmet information and support needs of adults with craniosynostosis and highlight the benefits of co-production in research.

15.
J Am Chem Soc ; 145(8): 4450-4461, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36799625

RESUMEN

High voltage spinel is one of the most promising next-generation cobalt-free cathode materials for lithium ion battery applications. Besides the typically utilized compositional range of LixNi0.5Mn1.5O4 0 < x < 1 in the voltage window of 4.90-3.00 V, additional 1.5 mol of Li per formula unit can be introduced into the structure, in an extended voltage range to 1.50 V. Theoretically, this leads to significant increase of the specific energy from 690 to 1190 Wh/kg. However, utilization of the extended potential window leads to rapid capacity fading and voltage polarization that lack a comprehensive explanation. In this work, we conducted potentiostatic entropymetry, operando XRD and neutron diffraction on the ordered stoichiometric spinel LixNi0.5Mn1.5O4 within 0 < x < 2.5 in order to understand the dynamic structure evolution and correlate it with the voltage profile. During the two-phase reaction from cubic (x < 1) to tetragonal (x > 1) phase at ∼2.8 V, we identified the evolution of a second tetragonal phase with x > 2. The structural evaluation during the delithiation indicates the formation of an intermediate phase with cubic symmetry at a lithium content of x = 1.5. Evaluation of neutron diffraction data, with maximum entropy method, of the highly lithiated phase LixNi0.5Mn1.5O4 with 2 < x < 2.5 strongly suggests that lithium ions are located on octahedral 8a and tetrahedral 4a positions of the distorted tetragonal phase I41amd. Consequently, we were able to provide a conclusive explanation for the additional voltage step at 2.10 V, the sloping voltage profile below 1.80 V, and the additional voltage step at ∼3.80 V.

16.
Emerg Infect Dis ; 29(5): 977-987, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37081530

RESUMEN

Combining genomic and geospatial data can be useful for understanding Mycobacterium tuberculosis transmission in high-burden tuberculosis (TB) settings. We performed whole-genome sequencing on M. tuberculosis DNA extracted from sputum cultures from a population-based TB study conducted in Gaborone, Botswana, during 2012-2016. We determined spatial distribution of cases on the basis of shared genotypes among isolates. We considered clusters of isolates with ≤5 single-nucleotide polymorphisms identified by whole-genome sequencing to indicate recent transmission and clusters of ≥10 persons to be outbreaks. We obtained both molecular and geospatial data for 946/1,449 (65%) participants with culture-confirmed TB; 62 persons belonged to 5 outbreaks of 10-19 persons each. We detected geospatial clustering in just 2 of those 5 outbreaks, suggesting heterogeneous spatial patterns. Our findings indicate that targeted interventions applied in smaller geographic areas of high-burden TB identified using integrated genomic and geospatial data might help interrupt TB transmission during outbreaks.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Botswana/epidemiología , Tuberculosis/microbiología , Mycobacterium tuberculosis/genética , Genotipo , Genómica
17.
Kidney Int ; 104(5): 916-928, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37598854

RESUMEN

The phospholipase A2 receptor 1 (PLA2R1) is the major target antigen in patients with membranous nephropathy (MN), an antibody-mediated autoimmune glomerular disease. Investigation of MN pathogenesis has been hampered by the lack of reliable animal models. Here, we overcome this issue by generating a transgenic mouse line expressing a chimeric PLA2R1 (chPLA2R1) consisting of three human PLA2R1 domains (cysteine-rich, fibronectin type-II and CTLD1) and seven murine PLA2R1 domains (CTLD2-8) specifically in podocytes. Mice expressing the chPLA2R1 were healthy at birth and showed no major glomerular alterations when compared to mice with a wild-type PLA2R1 status. Upon active immunization with human PLA2R1 (hPLA2R1), chPLA2R1-positive mice developed anti-hPLA2R1 antibodies, a nephrotic syndrome, and all major histological features of MN, including granular deposition of mouse IgG and complement components in immunofluorescence and subepithelial electron-dense deposits and podocyte foot process effacement in electron microscopy. In order to investigate the role of the complement system in this model, we further crossed chPLA2R1-positive mice with mice lacking the central complement component C3 (C3-/- mice). Upon immunization with hPLA2R1, chPLA2R1-positive C3-/- mice had substantially less severe albuminuria and nephrotic syndrome when compared to chPLA2R1-positive mice with a wild-type C3 status. In conclusion, we introduce a novel active immunization model of PLA2R1-associated MN and demonstrate a pathogenic role of the complement system in this model.


Asunto(s)
Enfermedades Autoinmunes , Glomerulonefritis Membranosa , Síndrome Nefrótico , Humanos , Ratones , Animales , Receptores de Fosfolipasa A2/genética , Autoanticuerpos , Ratones Transgénicos , Vacunación , Complemento C3 , Modelos Animales de Enfermedad
18.
Kidney Int ; 103(2): 297-303, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36191868

RESUMEN

Antibody-mediated autoimmune pathologies like membranous nephropathy are difficult to model, particularly in the absence of local target antigen expression in model organisms such as mice and rats; as is the case for phospholipase A2 receptor 1 (PLA2R1), the major autoantigen in membranous nephropathy. Here, we generated a transgenic mouse line expressing the full-length human PLA2R1 in podocytes, which has no kidney impairment after birth. Beginning from the age of three weeks, these mice spontaneously developed anti-human PLA2R1 antibodies, a nephrotic syndrome with progressive albuminuria and hyperlipidemia, and the typical morphological signs of membranous nephropathy with granular glomerular deposition of murine IgG in immunofluorescence and subepithelial electron-dense deposits by electron microscopy. Importantly, human PLA2R1-expressing Rag2-/- mice, which lack mature and functioning B and T lymphocytes, developed neither anti-PLA2R1 antibodies nor proteinuria. Thus, our work demonstrates that podocyte expression of human PLA2R1 can induce membranous nephropathy with an underlying antibody-mediated pathogenesis in mice. Importantly, this antibody-mediated model enables proof-of-concept evaluations of antigen-specific treatment strategies, e.g., targeting autoantibodies or autoantibody-producing cells, and may further help understand the autoimmune pathogenesis of membranous nephropathy.


Asunto(s)
Glomerulonefritis Membranosa , Podocitos , Animales , Humanos , Ratones , Ratas , Autoanticuerpos , Autoantígenos/genética , Glomerulonefritis Membranosa/diagnóstico , Glomérulos Renales/patología , Podocitos/patología , Receptores de Fosfolipasa A2/genética , Ratones Transgénicos
19.
Kidney Int ; 104(6): 1092-1102, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37795587

RESUMEN

Membranous nephropathy (MN) is a pattern of injury caused by autoantibodies binding to specific target antigens, with accumulation of immune complexes along the subepithelial region of glomerular basement membranes. The past 20 years have brought revolutionary advances in the understanding of MN, particularly via the discovery of novel target antigens and their respective autoantibodies. These discoveries have challenged the traditional classification of MN into primary and secondary forms. At least 14 target antigens have been identified, accounting for 80%-90% of cases of MN. Many of the forms of MN associated with these novel MN target antigens have distinctive clinical and pathologic phenotypes. The Mayo Clinic consensus report on MN proposes a 2-step classification of MN. The first step, when possible, is identification of the target antigen, based on a multistep algorithm and using a combination of serology, staining of the kidney biopsy tissue by immunofluorescence or immunohistochemistry, and/or mass spectrometry methodology. The second step is the search for a potential underlying disease or associated condition, which is particularly relevant when knowledge of the target antigen is available to direct it. The meeting acknowledges that the resources and equipment required to perform the proposed testing may not be generally available. However, the meeting consensus was that the time has come to adopt an antigen-based classification of MN because this approach will allow for accurate and specific MN diagnosis, with significant implications for patient management and targeted treatment.


Asunto(s)
Glomerulonefritis Membranosa , Humanos , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/terapia , Consenso , Autoanticuerpos , Nefrectomía , Membrana Basal Glomerular/patología , Receptores de Fosfolipasa A2
20.
Ann Oncol ; 34(1): 70-77, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36209982

RESUMEN

BACKGROUND: During recent years, the burden of bureaucracy in clinical research has increased dramatically, adversely impacting the activity of investigators and clinical research teams. Although compliance with the Declaration of Helsinki, the guidelines for Good Clinical Practice (GCP), and other applicable regulations remains unquestionable, their overinterpretation and substitution by the internal operating procedures of sponsors and Contract Research Organizations (CROs) have increased the administrative burden. A survey conducted by the European Society for Medical Oncology (ESMO) Clinical Research Observatory (ECRO) among 940 investigators confirmed that they considered that the administrative burden in clinical research is excessive; that administrative procedures could be reduced without affecting the safety and the rights of the patients and the quality of the data; and that bureaucracy represents an obstacle for clinical research. METHODS: A panel of physicians with extensive experience in clinical research, composed by members of the ECRO and the ESMO Scientific Medical and Public Policy divisions, analyzed clinical trial procedures related to administrative workflow, pharmacovigilance, and medical care. RESULTS: The panel identified situations that generate debate between investigators and sponsors/CROs and selected real clinical scenarios that exemplify such situations. The panel discussed and proposed specific recommendations for those situations, based on GCP. CONCLUSIONS: This initiative aspires to streamline clinical research procedures and to become a platform for discussion among all clinical trial stakeholders, with the aim of promoting the sustainability of clinical research and the care of cancer patients.


Asunto(s)
Ensayos Clínicos como Asunto , Neoplasias , Humanos , Oncología Médica , Neoplasias/terapia
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