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1.
Science ; 385(6715): eadd8947, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39298586

RESUMEN

Humans with monogenic inborn errors responsible for extreme disease phenotypes can reveal essential physiological pathways. We investigated germline mutations in GNAI2, which encodes Gαi2, a key component in heterotrimeric G protein signal transduction usually thought to regulate adenylyl cyclase-mediated cyclic adenosine monophosphate (cAMP) production. Patients with activating Gαi2 mutations had clinical presentations that included impaired immunity. Mutant Gαi2 impaired cell migration and augmented responses to T cell receptor (TCR) stimulation. We found that mutant Gαi2 influenced TCR signaling by sequestering the guanosine triphosphatase (GTPase)-activating protein RASA2, thereby promoting RAS activation and increasing downstream extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)-AKT S6 signaling to drive cellular growth and proliferation.


Asunto(s)
Subunidad alfa de la Proteína de Unión al GTP Gi2 , Mutación de Línea Germinal , Receptores de Antígenos de Linfocitos T , Linfocitos T , Proteínas Activadoras de ras GTPasa , Humanos , Movimiento Celular/genética , Proliferación Celular , Subunidad alfa de la Proteína de Unión al GTP Gi2/genética , Inmunidad/genética , Sistema de Señalización de MAP Quinasas , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Activadoras de ras GTPasa/genética , Proteínas ras/metabolismo , Proteínas ras/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linaje
2.
J Parkinsons Dis ; 14(6): 1105-1114, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39121136

RESUMEN

Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share underlying neuropathology. Despite overlapping biology, therapeutic development has been approached separately for these clinical syndromes and there remains no treatment to slow, stop or prevent progression of clinical symptoms and development disability for people living with PD or DLB. Recent advances in biomarker tools, however, have paved new paths for biologic definition and staging of PD and DLB under a shared research framework. Patient-centered research funding organizations see the opportunity for a novel biological staging system for PD and DLB to accelerate and increase success of therapeutic development for the patient communities they serve. Amid growing momentum in the field to develop biological definitions for these neurodegenerative diseases, 7 international nonprofit organizations focused on PD and DLB came together to drive multistakeholder discussion and input on a biological staging system for research. The impact of these convenings to date can be seen in changes incorporated into a proposed biological staging system and growing alignment within the field to rapidly apply new scientific knowledge and biomarker tools to inform clinical trial design. In working together, likeminded nonprofit partners who were initially catalyzed by the significant potential for a biological staging system also realized the power of a shared voice in calling the field to action and have since worked together to establish a coalition to advance precompetitive progress and reduce hurdles to developing better treatments for PD, DLB and biologically related disorders.


Disease-focused nonprofit organizations serve to speed new treatments for patients through research funding and advocacy. In the Parkinson's disease (PD) and dementia with Lewy bodies (DLB) fields, several international nonprofit organizations came together to facilitate multistakeholder input on a new biological staging system for research. Stakeholders gathered included researchers, clinicians, drug developers, regulatory agencies, additional nonprofits, and people affected by PD and DLB. This example, fueled by a shared perspective that new drug development tools will improve clinical trials and get better treatments to patients sooner, serves as a model for continued collaborations across the PD and DLB fields. A new, international coalition of nonprofit organizations has emerged to support advancement of treatments to slow, stop, and one day prevent PD, DLB and related disorders, in part, by facilitating future multistakeholder collaborations.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Humanos , Biomarcadores/análisis , Enfermedad por Cuerpos de Lewy/diagnóstico , Enfermedad por Cuerpos de Lewy/terapia , Organizaciones sin Fines de Lucro , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/terapia
3.
J Parkinsons Dis ; 14(4): 809-821, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38701161

RESUMEN

Background: Patient and public involvement and engagement (PPIE) in the design of trials is important, as participant experience critically impacts delivery. The Edmond J Safra Accelerating Clinical Trials in PD (EJS ACT-PD) initiative is a UK consortium designing a platform trial for disease modifying therapies in PD. Objective: The integration of PPIE in all aspects of trial design and its evaluation throughout the project. Methods: PwP and care partners were recruited to a PPIE working group (WG) via UK Parkinson's charities, investigator patient groups and participants of a Delphi study on trial design. They are supported by charity representatives, trial delivery experts, researchers and core project team members. PPIE is fully embedded within the consortium's five other WGs and steering group. The group's terms of reference, processes for effective working and PPIE evaluation were co-developed with PPIE contributors. Results: 11 PwP and 4 care partners have supported the PPIE WG and contributed to the development of processes for effective working. A mixed methods research-in-action study is ongoing to evaluate PPIE within the consortium. This includes the Patient Engagement in Research Scale -a quantitative PPIE quality measure; semi-structured interviews -identifying areas for improvement and overall impressions of involvement; process fidelity- recording adherence; project documentation review - identifying impact of PPIE on project outputs. Conclusions: We provide a practical example of PPIE in complex projects. Evaluating feasibility, experiences and impact of PPIE involvement in EJS ACT-PD will inform similar programs on effective strategies. This will help enable future patient-centered research.


Asunto(s)
Ensayos Clínicos como Asunto , Enfermedad de Parkinson , Participación del Paciente , Humanos , Enfermedad de Parkinson/terapia , Ensayos Clínicos como Asunto/normas , Proyectos de Investigación , Participación de la Comunidad , Reino Unido , Técnica Delphi
4.
J Parkinsons Dis ; 14(4): 657-666, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38578902

RESUMEN

In 2011, the UK medical research charity Cure Parkinson's set up the international Linked Clinical Trials (iLCT) committee to help expedite the clinical testing of potentially disease modifying therapies for Parkinson's disease (PD). The first committee meeting was held at the Van Andel Institute in Grand Rapids, Michigan in 2012. This group of PD experts has subsequently met annually to assess and prioritize agents that may slow the progression of this neurodegenerative condition, using a systematic approach based on preclinical, epidemiological and, where possible, clinical data. Over the last 12 years, 171 unique agents have been evaluated by the iLCT committee, and there have been 21 completed clinical studies and 20 ongoing trials associated with the initiative. In this review, we briefly outline the iLCT process as well as the clinical development and outcomes of some of the top prioritized agents. We also discuss a few of the lessons that have been learnt, and we conclude with a perspective on what the next decade may bring, including the introduction of multi-arm, multi-stage clinical trial platforms and the possibility of combination therapies for PD.


Asunto(s)
Ensayos Clínicos como Asunto , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Antiparkinsonianos/uso terapéutico
6.
Nat Immunol ; 25(2): 282-293, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38172257

RESUMEN

Preserving cells in a functional, non-senescent state is a major goal for extending human healthspans. Model organisms reveal that longevity and senescence are genetically controlled, but how genes control longevity in different mammalian tissues is unknown. Here, we report a new human genetic disease that causes cell senescence, liver and immune dysfunction, and early mortality that results from deficiency of GIMAP5, an evolutionarily conserved GTPase selectively expressed in lymphocytes and endothelial cells. We show that GIMAP5 restricts the pathological accumulation of long-chain ceramides (CERs), thereby regulating longevity. GIMAP5 controls CER abundance by interacting with protein kinase CK2 (CK2), attenuating its ability to activate CER synthases. Inhibition of CK2 and CER synthase rescues GIMAP5-deficient T cells by preventing CER overaccumulation and cell deterioration. Thus, GIMAP5 controls longevity assurance pathways crucial for immune function and healthspan in mammals.


Asunto(s)
Ceramidas , Proteínas de Unión al GTP , Animales , Humanos , Longevidad/genética , Células Endoteliales/metabolismo , Mamíferos/metabolismo
7.
J Allergy Clin Immunol ; 153(6): 1655-1667, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38154666

RESUMEN

BACKGROUND: Functional T-cell responses are essential for virus clearance and long-term protection after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, whereas certain clinical factors, such as older age and immunocompromise, are associated with worse outcome. OBJECTIVE: We sought to study the breadth and magnitude of T-cell responses in patients with coronavirus disease 2019 (COVID-19) and in individuals with inborn errors of immunity (IEIs) who had received COVID-19 mRNA vaccine. METHODS: Using high-throughput sequencing and bioinformatics tools to characterize the T-cell receptor ß repertoire signatures in 540 individuals after SARS-CoV-2 infection, 31 IEI recipients of COVID-19 mRNA vaccine, and healthy controls, we quantified HLA class I- and class II-restricted SARS-CoV-2-specific responses and also identified several HLA allele-clonotype motif associations in patients with COVID-19, including a subcohort of anti-type 1 interferon (IFN-1)-positive patients. RESULTS: Our analysis revealed that elderly patients with COVID-19 with critical disease manifested lower SARS-CoV-2 T-cell clonotype diversity as well as T-cell responses with reduced magnitude, whereas the SARS-CoV-2-specific clonotypes targeted a broad range of HLA class I- and class II-restricted epitopes across the viral proteome. The presence of anti-IFN-I antibodies was associated with certain HLA alleles. Finally, COVID-19 mRNA immunization induced an increase in the breadth of SARS-CoV-2-specific clonotypes in patients with IEIs, including those who had failed to seroconvert. CONCLUSIONS: Elderly individuals have impaired capacity to develop broad and sustained T-cell responses after SARS-CoV-2 infection. Genetic factors may play a role in the production of anti-IFN-1 antibodies. COVID-19 mRNA vaccines are effective in inducing T-cell responses in patients with IEIs.


Asunto(s)
COVID-19 , Huésped Inmunocomprometido , SARS-CoV-2 , Humanos , COVID-19/inmunología , SARS-CoV-2/inmunología , Masculino , Persona de Mediana Edad , Femenino , Huésped Inmunocomprometido/inmunología , Adulto , Anciano , Linfocitos T/inmunología , Vacunas contra la COVID-19/inmunología , Inmunocompetencia/inmunología
8.
Curr Biol ; 33(13): 2728-2741.e3, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37343559

RESUMEN

Oncogenic Ras has been shown to change the way cancer cells divide by increasing the forces generated during mitotic rounding. In this way, RasV12 enables cancer cells to divide across a wider range of mechanical environments than normal cells. Here, we identify a further role for oncogenic Ras-ERK signaling in division by showing that RasV12 expression alters the shape, division orientation, and respreading dynamics of cells as they exit mitosis. Many of these effects appear to result from the impact of RasV12 signaling on actomyosin contractility, because RasV12 induces the severing of retraction fibers that normally guide spindle positioning and provide a memory of the interphase cell shape. In support of this idea, the RasV12 phenotype is reversed by inhibition of actomyosin contractility and can be mimicked by the loss of cell-substrate adhesion during mitosis. Finally, we show that RasV12 activation also perturbs division orientation in cells cultured in 2D epithelial monolayers and 3D spheroids. Thus, the induction of oncogenic Ras-ERK signaling leads to rapid changes in division orientation that, along with the effects of RasV12 on cell growth and cell-cycle progression, are likely to disrupt epithelial tissue organization and contribute to cancer dissemination.


Asunto(s)
Actomiosina , Mitosis , Actomiosina/metabolismo , Proliferación Celular , Genes ras , Citoesqueleto de Actina/metabolismo , Huso Acromático/metabolismo
9.
J Parkinsons Dis ; 13(3): 329-332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36911949

RESUMEN

There is a fundamental gap in knowledge in how Parkinson's disease manifests and affects women throughout their hormonal life cycle, resulting in unmet needs and adversely impacting women's quality of life. A set of questionnaires was developed and deployed through Fox Insight (open access) to address these issues by gathering data. This is the data from the first survey. The data from the questions regarding self-image were striking. 61% of women report that their Parkinson's disease negatively impacts their self-image. Here we explore the negative impact of Parkinson's disease on women to begin to fill the gaps in knowledge.


Asunto(s)
Menopausia , Enfermedad de Parkinson , Femenino , Humanos , Calidad de Vida , Autoimagen , Encuestas y Cuestionarios
11.
J Oncol Pharm Pract ; 29(2): 416-421, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36567674

RESUMEN

OBJECTIVE: Off-protocol prescribing of systemic anti-cancer therapy (SACT) can lead to concerns about effectiveness of patient care. To identify variations in practice, a toolkit was developed for health services to address patient safety and the risk of sub-optimal outcomes for patients. DATA SOURCES: Following significant incidents with SACT in South Australia and New South Wales, the Department of Health and Human Services, Victoria (the department) conducted an assessment of Victorian public health services to understand current practice regarding SACT protocol governance. A literature review examining SACT auditing was also undertaken to guide improvements. A department supported Chemotherapy Audit Toolkit (CAT) was created for implementation at public hospitals in Victoria. A post-implementation survey was done on uptake and issue identification. DATA SUMMARY: An initial assessment showed that 27% of Victorian public health services were undertaking retrospective review of SACT dosing, which was targeted for improvement. The literature review identified little guidance, however an audit of current sector practices found several audit methodologies. A process that involved audits by health services assessing their own practice was adopted. The toolkit was developed and piloted with health services. A post-implementation survey showed that 20% of services were using the toolkit, 35% were implementing the toolkit and 45% did not use the toolkit. CONCLUSIONS: The VicTAG CAT has been adopted by more than half of Victorian public health services and is being used to influence prescribing. Implementation of the toolkit has been affected by resource reallocation due to the COVID-19 pandemic. The CAT is available online.


Asunto(s)
COVID-19 , Neoplasias , Humanos , Pandemias , Neoplasias/tratamiento farmacológico , Estudios Retrospectivos
12.
Trends Cell Biol ; 33(1): 60-69, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36175301

RESUMEN

Mutations in RAS are key oncogenic drivers and therapeutic targets. Oncogenic Ras proteins activate a network of downstream signalling pathways, including extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3-kinase (PI3K), promoting cell proliferation and survival. However, there is increasing evidence that RAS oncogenes also alter the mechanical properties of both individual malignant cells and transformed tissues. Here we discuss the role of oncogenic RAS in controlling mechanical cell phenotypes and how these mechanical changes promote oncogenic transformation in single cells and tissues. RAS activation alters actin organisation and actomyosin contractility. These changes alter cell rheology and impact mechanosensing through changes in substrate adhesion and YAP/TAZ-dependent mechanotransduction. We then discuss how these changes play out in cell collectives and epithelial tissues by driving large-scale tissue deformations and the expansion of malignant cells. Uncovering how RAS oncogenes alter cell mechanics will lead to a better understanding of the morphogenetic processes that underlie tumour formation in RAS-mutant cancers.


Asunto(s)
Genes ras , Neoplasias , Humanos , Mecanotransducción Celular , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Actinas/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Neoplasias/genética , Oncogenes
13.
Int J Biol Sci ; 18(15): 5591-5606, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36263161

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the pandemic respiratory infectious disease COVID-19. However, clinical manifestations and outcomes differ significantly among COVID-19 patients, ranging from asymptomatic to extremely severe, and it remains unclear what drives these disparities. Here, we studied 159 sequentially enrolled hospitalized patients with COVID-19-associated pneumonia from Brescia, Italy using the VirScan phage-display method to characterize circulating antibodies binding to 96,179 viral peptides encoded by 1,276 strains of human viruses. SARS-CoV-2 infection was associated with a marked increase in immune antibody repertoires against many known pathogenic and non-pathogenic human viruses. This antiviral antibody response was linked to longitudinal trajectories of disease severity and was further confirmed in additional 125 COVID-19 patients from the same geographical region in Northern Italy. By applying a machine-learning-based strategy, a viral exposure signature predictive of COVID-19-related disease severity linked to patient survival was developed and validated. These results provide a basis for understanding the role of memory B-cell repertoire to viral epitopes in COVID-19-related symptoms and suggest that a unique anti-viral antibody repertoire signature may be useful to define COVID-19 clinical severity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Viroma , Antivirales , Epítopos
14.
medRxiv ; 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36093351

RESUMEN

Multisystem Inflammatory Syndrome in Children (MIS-C) is a systemic inflammatory condition that follows SARS-CoV2 infection or exposure in children. Clinical presentations are highly variable and include fever, gastrointestinal (GI) disease, shock, and Kawasaki Disease-like illness (MIS-C/KD). Compared to patients with acute COVID, patients with MIS-C have a distinct immune signature and expansion of TRVB11 expressing T cells. However, the relationship between immunological and clinical phenotypes of MIS-C is unknown. Here, we measured serum biomarkers, TCR repertoire, and SARS-CoV2-specific T cell responses in a cohort of 76 MIS-C patients. Serum biomarkers associated with macrophage and Th1 activation were elevated in patients with shock, consistent with previous reports. Significantly increased SARS-CoV-2-induced IFN-γ, IL-2, and TNF-α production were seen in CD4 + T cells from patients with neurologic involvement and respiratory failure. Diarrhea was associated with a significant reduction in shock-associated serum biomarkers, suggesting a protective effect. TRVB11 usage was highly associated with MIS-C/KD and coronary aneurysms, suggesting a potential biomarker for these manifestations in MIS-C patients. By identifying novel immunologic associations with the different clinical phenotypes of MIS-C, this study provides insights into the clinical heterogeneity of MIS-C. These unique immunophenotypic associations could provide biomarkers to identify patients at risk for severe complications of MIS-C, including shock and MIS-C/KD.

15.
Pharmaceut Med ; 36(5): 279-286, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35953655

RESUMEN

Life science research and development (R&D) companies are all too aware of the importance of patient perspectives but also of the barriers to engaging directly with patients, not least compliance, complex technical and regulatory issues, and the need to meet multifaceted expectations. Medical research charities (MRCs), highly technical and professional organisations, work directly with patients; they represent an expert resource for the science of their field, for disease-related patient advocacy issues and to advise and assist R&D companies in devising meaningful trials. The Pistoia Alliance, a non-profit organisation facilitating life sciences R&D, gathered a number of UK MRCs focused on complex lifelong conditions. The group used workshops and an opinion questionnaire for a snapshot of how the charities believe their knowledge and patient experiences could contribute insights and efficiencies to commercial R&D. MRCs argued that for chronic conditions, the patient perspective is vital in facilitating and de-risking trials, promoting patient motivation, compliance and study viability. MRCs and the patients they represent want to see successful trials, and it is in everyone's interest that well considered studies can proceed. Today, with remote assessments, consumer wearables and digital health technologies, MRCs and patients are already collating substantial data sets that are relevant to quality-of-life benefits, regulatory and value assessments, all of great interest to biopharmaceutical companies. In turn, MRCs would benefit from the experience of biopharma in generating clinical data and implementing novel technologies.


Asunto(s)
Productos Biológicos , Disciplinas de las Ciencias Biológicas , Investigación Biomédica , Organizaciones de Beneficencia , Humanos , Organizaciones sin Fines de Lucro
16.
Cell ; 185(7): 1172-1188.e28, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35303419

RESUMEN

Intestinal mucus forms the first line of defense against bacterial invasion while providing nutrition to support microbial symbiosis. How the host controls mucus barrier integrity and commensalism is unclear. We show that terminal sialylation of glycans on intestinal mucus by ST6GALNAC1 (ST6), the dominant sialyltransferase specifically expressed in goblet cells and induced by microbial pathogen-associated molecular patterns, is essential for mucus integrity and protecting against excessive bacterial proteolytic degradation. Glycoproteomic profiling and biochemical analysis of ST6 mutations identified in patients show that decreased sialylation causes defective mucus proteins and congenital inflammatory bowel disease (IBD). Mice harboring a patient ST6 mutation have compromised mucus barriers, dysbiosis, and susceptibility to intestinal inflammation. Based on our understanding of the ST6 regulatory network, we show that treatment with sialylated mucin or a Foxo3 inhibitor can ameliorate IBD.


Asunto(s)
Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Sialiltransferasas/genética , Animales , Homeostasis , Humanos , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Ratones , Moco/metabolismo , Sialiltransferasas/metabolismo , Simbiosis
17.
Nat Rev Mol Cell Biol ; 23(1): 74-88, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34508254

RESUMEN

Cancer is a group of diseases in which cells divide continuously and excessively. Cell division is tightly regulated by multiple evolutionarily conserved cell cycle control mechanisms, to ensure the production of two genetically identical cells. Cell cycle checkpoints operate as DNA surveillance mechanisms that prevent the accumulation and propagation of genetic errors during cell division. Checkpoints can delay cell cycle progression or, in response to irreparable DNA damage, induce cell cycle exit or cell death. Cancer-associated mutations that perturb cell cycle control allow continuous cell division chiefly by compromising the ability of cells to exit the cell cycle. Continuous rounds of division, however, create increased reliance on other cell cycle control mechanisms to prevent catastrophic levels of damage and maintain cell viability. New detailed insights into cell cycle control mechanisms and their role in cancer reveal how these dependencies can be best exploited in cancer treatment.


Asunto(s)
Puntos de Control del Ciclo Celular , Neoplasias/patología , Animales , Daño del ADN/genética , Replicación del ADN/genética , Humanos , Neoplasias/genética , Neoplasias/terapia , Oncogenes , Huso Acromático/metabolismo
18.
J Parkinsons Dis ; 12(1): 95-103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34744054

RESUMEN

A recent breakthrough paper published in Science Translational Medicine has provided compelling evidence that inhibition of Parkin Interacting Substrate (PARIS) may offer clinical researchers an important new therapeutic approach since it shows considerable promise as an important biological target potentially capable of pharmaceutical intervention to slow long term neurodegeneration in patients with Parkinson's disease (PD). We present several PD-relevant perspectives on this paper that were not discussed in that otherwise entirely scientific narrative. We also outline the some of the work leading up to it, including the massive drug screen that proved necessary to discover a clinically suitable inhibitor of PARIS (Farnesol), as well as relevant PD research within the wider drug class, issues surrounding its future formulation, and next steps in translating this new knowledge into the clinic to evaluate possible long-term PD patient benefits.


Asunto(s)
Neuronas Dopaminérgicas , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Proteínas Represoras , Ubiquitina-Proteína Ligasas
19.
J Clin Immunol ; 42(1): 108-118, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655400

RESUMEN

X-linked MAGT1 deficiency with increased susceptibility to Epstein-Barr virus (EBV) infection and N-linked glycosylation defect (XMEN) disease is an inborn error of immunity caused by loss-of-function mutations in the magnesium transporter 1 (MAGT1) gene. The original studies of XMEN patients focused on impaired magnesium regulation, leading to decreased EBV-cytotoxicity and the loss of surface expression of the activating receptor "natural killer group 2D" (NKG2D) on CD8+ T cells and NK cells. In vitro studies showed that supraphysiological supplementation of magnesium rescued these defects. Observational studies in 2 patients suggested oral magnesium supplementation could decrease EBV viremia. Hence, we performed a randomized, double-blind, placebo-controlled, crossover study in 2 parts. In part 1, patients received either oral magnesium L-threonate (MLT) or placebo for 12 weeks followed by 12 weeks of the other treatment. Part 2 began with 3 days of high-dose intravenous (IV) magnesium sulfate (MgSO4) followed by open-label MLT for 24 weeks. One EBV-infected and 3 EBV-naïve patients completed part 1. One EBV-naïve patient was removed from part 2 of the study due to asymptomatic elevation of liver enzymes during IV MgSO4. No change in EBV or NKG2D status was observed. In vitro magnesium supplementation experiments in cells from 14 XMEN patients failed to significantly rescue NKG2D expression and the clinical trial was stopped. Although small, this study indicates magnesium supplementation is unlikely to be an effective therapeutic option in XMEN disease.


Asunto(s)
Proteínas de Transporte de Catión , Infecciones por Virus de Epstein-Barr , Neoplasias , Enfermedades por Inmunodeficiencia Combinada Ligada al Cromosoma X , Linfocitos T CD8-positivos , Proteínas de Transporte de Catión/genética , Estudios Cruzados , Suplementos Dietéticos , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/fisiología , Humanos , Magnesio/metabolismo , Magnesio/uso terapéutico , Neoplasias/genética , Enfermedades por Inmunodeficiencia Combinada Ligada al Cromosoma X/genética
20.
Nat Immunol ; 23(1): 75-85, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34937930

RESUMEN

We report a pleiotropic disease due to loss-of-function mutations in RHBDF2, the gene encoding iRHOM2, in two kindreds with recurrent infections in different organs. One patient had recurrent pneumonia but no colon involvement, another had recurrent infectious hemorrhagic colitis but no lung involvement and the other two experienced recurrent respiratory infections. Loss of iRHOM2, a rhomboid superfamily member that regulates the ADAM17 metalloproteinase, caused defective ADAM17-dependent cleavage and release of cytokines, including tumor-necrosis factor and amphiregulin. To understand the diverse clinical phenotypes, we challenged Rhbdf2-/- mice with Pseudomonas aeruginosa by nasal gavage and observed more severe pneumonia, whereas infection with Citrobacter rodentium caused worse inflammatory colitis than in wild-type mice. The fecal microbiota in the colitis patient had characteristic oral species that can predispose to colitis. Thus, a human immunodeficiency arising from iRHOM2 deficiency causes divergent disease phenotypes that can involve the local microbial environment.


Asunto(s)
Proteína ADAM17/genética , Proteínas Portadoras/genética , Enfermedades de Inmunodeficiencia Primaria/genética , Células A549 , Animales , Niño , Preescolar , Citrobacter rodentium/patogenicidad , Colitis/genética , Citocinas/genética , Infecciones por Enterobacteriaceae/genética , Femenino , Células HEK293 , Humanos , Recién Nacido , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Mutación/genética , Infecciones por Pseudomonas/genética , Pseudomonas aeruginosa/patogenicidad , Transducción de Señal/genética
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