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1.
EMBO Rep ; 25(1): 254-285, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38177910

RESUMEN

Midbrain dopaminergic neurons (mDANs) control voluntary movement, cognition, and reward behavior under physiological conditions and are implicated in human diseases such as Parkinson's disease (PD). Many transcription factors (TFs) controlling human mDAN differentiation during development have been described, but much of the regulatory landscape remains undefined. Using a tyrosine hydroxylase (TH) human iPSC reporter line, we here generate time series transcriptomic and epigenomic profiles of purified mDANs during differentiation. Integrative analysis predicts novel regulators of mDAN differentiation and super-enhancers are used to identify key TFs. We find LBX1, NHLH1 and NR2F1/2 to promote mDAN differentiation and show that overexpression of either LBX1 or NHLH1 can also improve mDAN specification. A more detailed investigation of TF targets reveals that NHLH1 promotes the induction of neuronal miR-124, LBX1 regulates cholesterol biosynthesis, and NR2F1/2 controls neuronal activity.


Asunto(s)
Neuronas Dopaminérgicas , Células Madre Pluripotentes Inducidas , Humanos , Neuronas Dopaminérgicas/metabolismo , Multiómica , Mesencéfalo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Diferenciación Celular/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética
2.
Ann Neurol ; 96(1): 133-149, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38767023

RESUMEN

OBJECTIVE: The aim of our study is to better understand the genetic architecture and pathological mechanisms underlying neurodegeneration in idiopathic Parkinson's disease (iPD). We hypothesized that a fraction of iPD patients may harbor a combination of common variants in nuclear-encoded mitochondrial genes ultimately resulting in neurodegeneration. METHODS: We used mitochondria-specific polygenic risk scores (mitoPRSs) and created pathway-specific mitoPRSs using genotype data from different iPD case-control datasets worldwide, including the Luxembourg Parkinson's Study (412 iPD patients and 576 healthy controls) and COURAGE-PD cohorts (7,270 iPD cases and 6,819 healthy controls). Cellular models from individuals stratified according to the most significant mitoPRS were subsequently used to characterize different aspects of mitochondrial function. RESULTS: Common variants in genes regulating Oxidative Phosphorylation (OXPHOS-PRS) were significantly associated with a higher PD risk in independent cohorts (Luxembourg Parkinson's Study odds ratio, OR = 1.31[1.14-1.50], p-value = 5.4e-04; COURAGE-PD OR = 1.23[1.18-1.27], p-value = 1.5e-29). Functional analyses in fibroblasts and induced pluripotent stem cells-derived neuronal progenitors revealed significant differences in mitochondrial respiration between iPD patients with high or low OXPHOS-PRS (p-values < 0.05). Clinically, iPD patients with high OXPHOS-PRS have a significantly earlier age at disease onset compared to low-risk patients (false discovery rate [FDR]-adj p-value = 0.015), similar to prototypic monogenic forms of PD. Finally, iPD patients with high OXPHOS-PRS responded more effectively to treatment with mitochondrially active ursodeoxycholic acid. INTERPRETATION: OXPHOS-PRS may provide a precision medicine tool to stratify iPD patients into a pathogenic subgroup genetically defined by specific mitochondrial impairment, making these individuals eligible for future intelligent clinical trial designs. ANN NEUROL 2024;96:133-149.


Asunto(s)
Mitocondrias , Herencia Multifactorial , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/patología , Herencia Multifactorial/genética , Mitocondrias/genética , Masculino , Femenino , Fosforilación Oxidativa , Persona de Mediana Edad , Anciano , Estudios de Casos y Controles , Células Madre Pluripotentes Inducidas , Predisposición Genética a la Enfermedad/genética , Puntuación de Riesgo Genético
3.
Mol Cell Neurosci ; 128: 103919, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38307302

RESUMEN

Parkinson's disease (PD) is a complex, progressive neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta in the midbrain. Despite extensive research efforts, the molecular and cellular changes that precede neurodegeneration in PD are poorly understood. To address this, here we describe the use of patient specific human midbrain organoids harboring the SNCA triplication to investigate mechanisms underlying dopaminergic degeneration. Our midbrain organoid model recapitulates key pathological hallmarks of PD, including the aggregation of α-synuclein and the progressive loss of dopaminergic neurons. We found that these pathological hallmarks are associated with an increase in senescence associated cellular phenotypes in astrocytes including nuclear lamina defects, the presence of senescence associated heterochromatin foci, and the upregulation of cell cycle arrest genes. These results suggest a role of pathological α-synuclein in inducing astrosenescence which may, in turn, increase the vulnerability of dopaminergic neurons to degeneration.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Astrocitos/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Mesencéfalo/metabolismo , Mesencéfalo/patología , Neuronas Dopaminérgicas/metabolismo , Organoides/metabolismo , Organoides/patología , Sustancia Negra/metabolismo
4.
Biol Proced Online ; 25(1): 26, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730545

RESUMEN

BACKGROUND: Astrocytes have recently gained attention as key contributors to the pathogenesis of neurodegenerative disorders including Parkinson's disease. To investigate human astrocytes in vitro, numerous differentiation protocols have been developed. However, the properties of the resulting glia are inconsistent, which complicates the selection of an appropriate method for a given research question. Thus, we compared two approaches for the generation of iPSC-derived astrocytes. We phenotyped glia that were obtained employing a widely used long, serum-free ("LSF") method against an in-house established short, serum-containing ("SSC") protocol which allows for the generation of astrocytes and midbrain neurons from the same precursor cells. RESULTS: We employed high-content confocal imaging and RNA sequencing to characterize the cultures. The astrocytes generated with the LSF or SSC protocols differed considerably in their properties: while the former cells were more labor-intense in their generation (5 vs 2 months), they were also more mature. This notion was strengthened by data resulting from cell type deconvolution analysis that was applied to bulk transcriptomes from the cultures to assess their similarity with human postmortem astrocytes. CONCLUSIONS: Overall, our analyses highlight the need to consider the advantages and disadvantages of a given differentiation protocol, when designing functional or drug discovery studies involving iPSC-derived astrocytes.

5.
Brain ; 145(3): 964-978, 2022 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-34919646

RESUMEN

Idiopathic Parkinson's disease is characterized by a progressive loss of dopaminergic neurons, but the exact disease aetiology remains largely unknown. To date, Parkinson's disease research has mainly focused on nigral dopaminergic neurons, although recent studies suggest disease-related changes also in non-neuronal cells and in midbrain regions beyond the substantia nigra. While there is some evidence for glial involvement in Parkinson's disease, the molecular mechanisms remain poorly understood. The aim of this study was to characterize the contribution of all cell types of the midbrain to Parkinson's disease pathology by single-nuclei RNA sequencing and to assess the cell type-specific risk for Parkinson's disease using the latest genome-wide association study. We profiled >41 000 single-nuclei transcriptomes of post-mortem midbrain from six idiopathic Parkinson's disease patients and five age-/sex-matched controls. To validate our findings in a spatial context, we utilized immunolabelling of the same tissues. Moreover, we analysed Parkinson's disease-associated risk enrichment in genes with cell type-specific expression patterns. We discovered a neuronal cell cluster characterized by CADPS2 overexpression and low TH levels, which was exclusively present in idiopathic Parkinson's disease midbrains. Validation analyses in laser-microdissected neurons suggest that this cluster represents dysfunctional dopaminergic neurons. With regard to glial cells, we observed an increase in nigral microglia in Parkinson's disease patients. Moreover, nigral idiopathic Parkinson's disease microglia were more amoeboid, indicating an activated state. We also discovered a reduction in idiopathic Parkinson's disease oligodendrocyte numbers with the remaining cells being characterized by a stress-induced upregulation of S100B. Parkinson's disease risk variants were associated with glia- and neuron-specific gene expression patterns in idiopathic Parkinson's disease cases. Furthermore, astrocytes and microglia presented idiopathic Parkinson's disease-specific cell proliferation and dysregulation of genes related to unfolded protein response and cytokine signalling. While reactive patient astrocytes showed CD44 overexpression, idiopathic Parkinson's disease microglia revealed a pro-inflammatory trajectory characterized by elevated levels of IL1B, GPNMB and HSP90AA1. Taken together, we generated the first single-nuclei RNA sequencing dataset from the idiopathic Parkinson's disease midbrain, which highlights a disease-specific neuronal cell cluster as well as 'pan-glial' activation as a central mechanism in the pathology of the movement disorder. This finding warrants further research into inflammatory signalling and immunomodulatory treatments in Parkinson's disease.


Asunto(s)
Enfermedad de Parkinson , Neuronas Dopaminérgicas/metabolismo , Estudio de Asociación del Genoma Completo , Humanos , Glicoproteínas de Membrana/metabolismo , Mesencéfalo , Microglía/metabolismo , Enfermedad de Parkinson/metabolismo , Sustancia Negra/metabolismo
6.
Saudi Pharm J ; 31(12): 101867, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38028212

RESUMEN

Costs of hemophilia A treatment are increasing. Waste of clotting products should be avoided. To estimate the first-year waste of emicizumab prophylaxis for people with hemophilia A and inhibitors (PwHAi) who failed immune tolerance induction (ITI), in Brazil. We evaluated the manufacturer and the Brazilian Ministry of Health (MoH) protocol-recommended regimens in a budget impact model. The loading dose consisted of 3.0 mg/kg/Q1W for 4 weeks, for both recommendations. The manufacturer maintenance regimens comprised 1.5 mg/kg/Q1W, 3.0 mg/kg/Q2W, and 6.0 mg/kg/Q4W. The MoH protocol maintenance regimen encompassed a hybrid Q1W/Q2W administration, depending on the body weight. The Q4W regimen was not recommended by the MoH protocol. Analyses were performed to estimate waste given its expense based on the World Health Organization body weight range (percentiles [P] 15, 50, and 85). The first-year emicizumab waste was estimated individually and for the disclosed PwHAi who failed ITI (n = 114). The highest emicizumab waste was estimated for the lowest body weights and the Q1W regimen. The Q4W regimen resulted in the lowest emicizumab waste, followed by the MoH protocol regimen. The total reconstituted costs estimated for the PwHAi who failed ITI according to the hybrid MoH protocol ranged from US$32,858,777 (P15) to US$47,186,858 (P85), with emicizumab waste ranging from 7.9 % (US$2,594,515) to 3.7 % (US$1,738,750), respectively. Lost resources due to current protocols for emicizumab prophylaxis for PwHAi who failed ITI in Brazil are considerable. Waste was more pronounced due to lower body weight and shorter administration intervals.

7.
Hum Mol Genet ; 29(8): 1353-1364, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-32280985

RESUMEN

Mitochondrial Rho GTPase 1 (Miro1) protein is a well-known adaptor for mitochondrial transport and also regulates mitochondrial quality control and function. Furthermore, Miro1 was associated with mitochondrial-endoplasmic reticulum (ER) contact sites (MERCs), which are key regulators of cellular calcium homeostasis and the initiation of autophagy. Impairments of these mechanisms were linked to neurodegeneration in Parkinson's disease (PD). We recently revealed that PD fibroblasts harboring Miro1 mutations displayed dysregulations in MERC organization and abundance, affecting mitochondrial homeostasis and clearance. We hypothesize that mutant Miro1 impairs the function of MERCs and mitochondrial dynamics, altering neuronal homeostasis and integrity in PD. PD skin fibroblasts harboring the Miro1-R272Q mutation were differentiated into patient-derived neurons. Live-cell imaging and immunocytochemistry were used to study mitophagy and the organization and function of MERCs. Markers of autophagy or mitochondrial function were assessed by western blotting. Quantification of organelle juxtapositions revealed an increased number of MERCs in patient-derived neurons. Live-cell imaging results showed alterations of mitochondrial dynamics and increased sensitivity to calcium stress, as well as reduced mitochondrial clearance. Finally, western blot analysis indicated a blockage of the autophagy flux in Miro1-mutant neurons. Miro1-mutant neurons display altered ER-mitochondrial tethering compared with control neurons. This alteration likely interferes with proper MERC function, contributing to a defective autophagic flux and cytosolic calcium handling capacity. Moreover, mutant Miro1 affects mitochondrial dynamics in neurons, which may result in disrupted mitochondrial turnover and altered mitochondrial movement.


Asunto(s)
Retículo Endoplásmico/genética , Mitocondrias/genética , Proteínas Mitocondriales/genética , Enfermedad de Parkinson/genética , Proteínas de Unión al GTP rho/genética , Calcio/metabolismo , Diferenciación Celular/genética , Citosol/metabolismo , Homeostasis/genética , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Dinámicas Mitocondriales/genética , Mitofagia/genética , Neuronas/metabolismo , Neuronas/patología , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología
8.
Mov Disord ; 37(7): 1405-1415, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35460111

RESUMEN

BACKGROUND: Mutations in the E3 ubiquitin ligase parkin cause autosomal recessive Parkinson's disease (PD). Together with PTEN-induced kinase 1 (PINK1), parkin regulates the clearance of dysfunctional mitochondria. New mitochondria are generated through an interplay of nuclear- and mitochondrial-encoded proteins, and recent studies suggest that parkin influences this process at both levels. In addition, parkin was shown to prevent mitochondrial membrane permeability, impeding mitochondrial DNA (mtDNA) escape and subsequent neuroinflammation. However, parkin's regulatory roles independent of mitophagy are not well described in patient-derived neurons. OBJECTIVES: We sought to investigate parkin's role in preventing neuronal mtDNA dyshomeostasis, release, and glial activation at the endogenous level. METHODS: We generated induced pluripotent stem cell (iPSC)-derived midbrain neurons from PD patients with parkin (PRKN) mutations and healthy controls. Live-cell imaging, proteomic, mtDNA integrity, and gene expression analyses were employed to investigate mitochondrial biogenesis and genome maintenance. To assess neuroinflammation, we performed single-nuclei RNA sequencing in postmortem tissue and quantified interleukin expression in mtDNA/lipopolysaccharides (LPS)-treated iPSC-derived neuron-microglia co-cultures. RESULTS: Neurons from patients with PRKN mutations revealed deficits in the mitochondrial biogenesis pathway, resulting in mtDNA dyshomeostasis. Moreover, the energy sensor sirtuin 1, which controls mitochondrial biogenesis and clearance, was downregulated in parkin-deficient cells. Linking mtDNA disintegration to neuroinflammation, in postmortem midbrain with PRKN mutations, we confirmed mtDNA dyshomeostasis and detected an upregulation of microglia overexpressing proinflammatory cytokines. Finally, parkin-deficient neuron-microglia co-cultures elicited an enhanced immune response when exposed to mtDNA/LPS. CONCLUSIONS: Our findings suggest that parkin coregulates mitophagy, mitochondrial biogenesis, and mtDNA maintenance pathways, thereby protecting midbrain neurons from neuroinflammation and degeneration. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
ADN Mitocondrial , Enfermedad de Parkinson , Ubiquitina-Proteína Ligasas , ADN Mitocondrial/genética , Humanos , Inflamación/genética , Lipopolisacáridos/farmacología , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Proteómica , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/genética
9.
Mov Disord ; 37(1): 80-94, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34637165

RESUMEN

BACKGROUND: The etiology of Parkinson's disease (PD) is only partially understood despite the fact that environmental causes, risk factors, and specific gene mutations are contributors to the disease. Biallelic mutations in the phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) gene involved in mitochondrial homeostasis, vesicle trafficking, and autophagy are sufficient to cause PD. OBJECTIVES: We sought to evaluate the difference between controls' and PINK1 patients' derived neurons in their transition from neuroepithelial stem cells to neurons, allowing us to identify potential pathways to target with repurposed compounds. METHODS: Using two-dimensional and three-dimensional models of patients' derived neurons we recapitulated PD-related phenotypes. We introduced the usage of midbrain organoids for testing compounds. Using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), we corrected the point mutations of three patients' derived cells. We evaluated the effect of the selected compound in a mouse model. RESULTS: PD patient-derived cells presented differences in their energetic profile, imbalanced proliferation, apoptosis, mitophagy, and a reduced differentiation efficiency to tyrosine hydroxylase positive (TH+) neurons compared to controls' cells. Correction of a patient's point mutation ameliorated the metabolic properties and neuronal firing rates as well as reversing the differentiation phenotype, and reducing the increased astrocytic levels. Treatment with 2-hydroxypropyl-ß-cyclodextrin increased the autophagy and mitophagy capacity of neurons concomitant with an improved dopaminergic differentiation of patient-specific neurons in midbrain organoids and ameliorated neurotoxicity in a mouse model. CONCLUSION: We show that treatment with a repurposed compound is sufficient for restoring the impaired dopaminergic differentiation of PD patient-derived cells. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , 2-Hidroxipropil-beta-Ciclodextrina/metabolismo , Animales , Encéfalo/metabolismo , Neuronas Dopaminérgicas/metabolismo , Humanos , Ratones , Neuronas/metabolismo , Organoides/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Fenotipo
10.
Br J Clin Pharmacol ; 88(4): 1551-1566, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34622475

RESUMEN

AIMS: The aim was to perform an umbrella review to summarise the existing evidence on proton-pump inhibitor (PPI) use and adverse outcomes and to grade the certainty of evidence. METHODS: Electronic databases were searched up to July 2021 for meta-analyses of cohort studies and/or randomised controlled trials (RCTs). Summary effect sizes from a random-effects model, between-study heterogeneity, 95% prediction interval, small-study effect, excess significance and credibility ceilings were devised to classify the credibility of evidence from meta-analyses of cohort studies, whereas the GRADE approach was used for meta-analyses of RCTs. RESULTS: In meta-analyses of cohort studies, 52 of the 91 examined associations were statistically significant (P ≤ .05). Convincing evidence emerged from main analysis for the association between PPI use and risk of all-site fracture and chronic kidney disease in the elderly population. However, none of these associations remained supported by convincing evidence after sensitivity analyses. The use of PPI is also associated with an increased risk of mortality due to COVID-19 infection and other related adverse outcomes, but the quality of evidence was weak. In meta-analyses of RCTs, 38 of the 63 examined associations were statistically significant. However, no associations were supported by high or moderate-quality evidence. CONCLUSION: This study's findings imply that most putative adverse outcomes associated with PPI use may not be supported by high-quality evidence and are likely to have been affected by underlying confounding factors. Future research is needed to confirm the causal association between PPI use and risk of fracture and chronic kidney disease.


Asunto(s)
COVID-19 , Insuficiencia Renal Crónica , Anciano , Humanos , Estudios de Cohortes , Metaanálisis como Asunto , Inhibidores de la Bomba de Protones/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Mov Disord ; 36(3): 704-715, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33142012

RESUMEN

BACKGROUND: VPS35 is part of the retromer complex and is responsible for the trafficking and recycling of proteins implicated in autophagy and lysosomal degradation, but also takes part in the degradation of mitochondrial proteins via mitochondria-derived vesicles. The p.D620N mutation of VPS35 causes an autosomal-dominant form of Parkinson's disease (PD), clinically representing typical PD. OBJECTIVE: Most of the studies on p.D620N VPS35 were performed on human tumor cell lines, rodent models overexpressing mutant VPS35, or in patient-derived fibroblasts. Here, based on identified target proteins, we investigated the implication of mutant VPS35 in autophagy, lysosomal degradation, and mitochondrial function in induced pluripotent stem cell-derived neurons from a patient harboring the p.D620N mutation. METHODS: We reprogrammed fibroblasts from a PD patient carrying the p.D620N mutation in the VPS35 gene and from two healthy donors in induced pluripotent stem cells. These were subsequently differentiated into neuronal precursor cells to finally generate midbrain dopaminergic neurons. RESULTS: We observed a decreased autophagic flux and lysosomal mass associated with an accumulation of α-synuclein in patient-derived neurons compared to controls. Moreover, patient-derived neurons presented a mitochondrial dysfunction with decreased membrane potential, impaired mitochondrial respiration, and increased production of reactive oxygen species associated with a defect in mitochondrial quality control via mitophagy. CONCLUSION: We describe for the first time the impact of the p.D620N VPS35 mutation on autophago-lysosome pathway and mitochondrial function in stem cell-derived neurons from an affected p.D620N carrier and define neuronal phenotypes for future pharmacological interventions. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Proteínas de Transporte Vesicular , Neuronas Dopaminérgicas/metabolismo , Humanos , Mitocondrias/metabolismo , Mutación/genética , Enfermedad de Parkinson/metabolismo , Transporte de Proteínas , Proteínas de Transporte Vesicular/genética , alfa-Sinucleína/metabolismo
12.
Mol Psychiatry ; 25(3): 629-639, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-29988083

RESUMEN

Common variants of about 20 genes contributing to AD risk have so far been identified through genome-wide association studies (GWAS). However, there is still a large proportion of heritability that might be explained by rare but functionally important variants. One of the so far identified genes with rare AD causing variants is ADAM10. Using whole-genome sequencing we now identified a single rare nonsynonymous variant (SNV) rs142946965 [p.R215I] in ADAM17 co-segregating with an autosomal-dominant pattern of late-onset AD in one family. Subsequent genotyping and analysis of available whole-exome sequencing data of additional case/control samples from Germany, UK, and USA identified five variant carriers among AD patients only. The mutation inhibits pro-protein cleavage and the formation of the active enzyme, thus leading to loss-of-function of ADAM17 alpha-secretase. Further, we identified a strong negative correlation between ADAM17 and APP gene expression in human brain and present in vitro evidence that ADAM17 negatively controls the expression of APP. As a consequence, p.R215I mutation of ADAM17 leads to elevated Aß formation in vitro. Together our data supports a causative association of the identified ADAM17 variant in the pathogenesis of AD.


Asunto(s)
Proteína ADAM17/genética , Enfermedad de Alzheimer/genética , Proteína ADAM17/metabolismo , Anciano , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Alemania , Humanos , Mutación con Pérdida de Función/genética , Masculino , Persona de Mediana Edad , Mutación , Secuenciación del Exoma
13.
Immunity ; 35(6): 972-85, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22177921

RESUMEN

Th17 cells have been described as short lived, but this view is at odds with their capacity to trigger protracted damage to normal and transformed tissues. We report that Th17 cells, despite displaying low expression of CD27 and other phenotypic markers of terminal differentiation, efficiently eradicated tumors and caused autoimmunity, were long lived, and maintained a core molecular signature resembling early memory CD8(+) cells with stem cell-like properties. In addition, we found that Th17 cells had high expression of Tcf7, a direct target of the Wnt and ß-catenin signaling axis, and accumulated ß-catenin, a feature observed in stem cells. In vivo, Th17 cells gave rise to Th1-like effector cell progeny and also self-renewed and persisted as IL-17A-secreting cells. Multipotency was required for Th17 cell-mediated tumor eradication because effector cells deficient in IFN-γ or IL-17A had impaired activity. Thus, Th17 cells are not always short lived and are a less-differentiated subset capable of superior persistence and functionality.


Asunto(s)
Células Madre/metabolismo , Células Th17/inmunología , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Supervivencia Celular/genética , Perfilación de la Expresión Génica , Interleucina-17/biosíntesis , Ratones , Ratones Transgénicos , Neoplasias/inmunología , Células Madre/citología , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células TH1/citología , Células TH1/inmunología , Células Th17/citología , Células Th17/metabolismo , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo
14.
J Immunol ; 200(9): 3304-3311, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29602773

RESUMEN

Immunotherapy is becoming the standard of care for melanoma. However, resistance to therapy is a major problem. Previously, we showed that tumor-specific, cytotoxic CD4+ T cells from tyrosinase-related protein 1 transgenic mice could overcome secondary resistance to recurring melanoma when anti-programmed cell death 1 ligand (PD-L1) checkpoint blockade was combined with either anti-lymphocyte-activated gene 3 (LAG-3) Abs or depletion of tumor-specific regulatory T (Treg) cells. In this study, we show that PD-L1 expressed by the host, not B16 melanoma, plays a major role in the early stages of exhaustion or primary resistance. We observed durable regression of melanoma in tumor-bearing PD-L1-/-RAG-/- mice with transfer of naive tumor-specific CD4+ T cells. However, exhausted tumor-specific CD4+ T cells, which included tumor-specific Treg cells, failed to maintain durable regression of tumors in PD-L1-/-RAG-/- mice unless tumor-specific Treg cells were eliminated, showing nonredundant pathways of resistance to immunotherapy were present. Translating these findings to a clinically relevant model of cancer immunotherapy, we unexpectedly showed that anti-PD-L1 checkpoint blockade mildly improved immunotherapy with tumor-specific CD4+ T cells and irradiation in wild-type mice. Instead, anti-LAG-3 checkpoint blockade, in combination with tumor-specific CD4+ T cells and irradiation, overcame primary resistance and treated established tumors resulting in fewer recurrences. Because LAG-3 negatively regulates effector T cell function and activates Treg cells, LAG-3 blockade may be more beneficial in overcoming primary resistance in combination immunotherapies using adoptive cellular therapy and irradiation than blockade of PD-L1.


Asunto(s)
Linfocitos T CD4-Positivos/trasplante , Resistencia a Antineoplásicos/inmunología , Inmunoterapia Adoptiva/métodos , Melanoma Experimental/inmunología , Neoplasias Cutáneas/inmunología , Animales , Antígenos CD/inmunología , Antígeno B7-H1/inmunología , Ratones , Ratones Transgénicos , Proteína del Gen 3 de Activación de Linfocitos
15.
J Immunol ; 198(10): 3869-3877, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28356385

RESUMEN

Th17 cells play a critical role in autoimmune diseases, including multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis. Response gene to complement (RGC)-32 is a cell cycle regulator and a downstream target of TGF-ß that mediates its profibrotic activity. In this study, we report that RGC-32 is preferentially upregulated during Th17 cell differentiation. RGC-32-/- mice have normal Th1, Th2, and regulatory T cell differentiation but show defective Th17 differentiation in vitro. The impaired Th17 differentiation is associated with defects in IFN regulatory factor 4, B cell-activating transcription factor, retinoic acid-related orphan receptor γt, and SMAD2 activation. In vivo, RGC-32-/- mice display an attenuated experimental autoimmune encephalomyelitis phenotype accompanied by decreased CNS inflammation and reduced frequency of IL-17- and GM-CSF-producing CD4+ T cells. Collectively, our results identify RGC-32 as a novel regulator of Th17 cell differentiation in vitro and in vivo and suggest that RGC-32 is a potential therapeutic target in multiple sclerosis and other Th17-mediated autoimmune diseases.


Asunto(s)
Diferenciación Celular/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Regulación de la Expresión Génica , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Células Th17/fisiología , Animales , Diferenciación Celular/efectos de los fármacos , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/fisiopatología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/metabolismo , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Proteínas Nucleares/deficiencia , Proteínas Nucleares/farmacología , Receptores de Ácido Retinoico/genética , Receptores de Ácido Retinoico/metabolismo , Células TH1/inmunología , Células Th17/inmunología , Células Th17/patología
16.
Indian J Med Res ; 147(6): 560-566, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-30168487

RESUMEN

Background & objectives: Genetic aberrations disrupting toll-like receptor and interferon homeostasis enhance the risk of systemic lupus erythematosus (SLE). Raised serum interferon-alpha (IFN-α) levels in SLE patients have been ascribed to polymorphism (rs2004640 G/T) in interferon regulatory factor 5 (IRF5) gene, resulting in enhanced transcript splicing. A positive association between IRF5 polymorphism and SLE risk has been reported in many populations. This study was aimed to find out frequency of IRF5 rs2004640 G/T polymorphism in patients with SLE and healthy controls and to assess its influence on susceptibility, clinical and serological characteristics of SLE. Methods: IRF5 rs2004640 (G/T) polymorphism was analyzed in 300 SLE patients and 460 age and sex matched controls by real-time PCR. Results: The IRF5 rs2004640 (G/T) polymorphism did not confer risk of SLE or influence clinical or serological phenotype. However, the mutant allele conferred a borderline risk to develop thrombocytopenia (odds ratio: 2.05, 95% confidence interval: 0.97-4.3, P=0.06) in patients with SLE. Interpretation & conclusions: Our study revealed that the IRF5 rs2004640 polymorphism was not a risk factor for SLE in population from south India. It may, however, be a useful genetic marker for thrombocytopenia in SLE patients. Although we could not demonstrate susceptibility toward lupus in the presence of IRF5 rs2004640 (G/T) polymorphism, further exploration of the genetic variability of IRF5 may help uncover its pathogenic role in Indian SLE patients.


Asunto(s)
Predisposición Genética a la Enfermedad , Factores Reguladores del Interferón/genética , Lupus Eritematoso Sistémico/genética , Estudios de Casos y Controles , Humanos , India , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Factores de Riesgo
17.
Dis Colon Rectum ; 60(1): 30-42, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27926555

RESUMEN

BACKGROUND: Radical surgery is associated with significant perioperative mortality in elderly and comorbid populations. Emerging data suggest for patients with a clinical complete response after neoadjuvant chemoradiotherapy that a watch-and-wait approach may provide equivalent survival and oncological outcomes. OBJECTIVE: The purpose of this study was to compare the cost-effectiveness of watch and wait and radical surgery for patients with rectal cancer after a clinical complete response following chemoradiotherapy. DESIGN: Decision analytical modeling and a Markov simulation were used to model long-term costs, quality-adjusted life-years, and cost-effectiveness after watch and wait and radical surgery. Sensitivity analysis was used to investigate the effect of uncertainty in model parameters. SETTINGS: A third-party payer perspective was adopted. PATIENTS: Patients included in the study were a 60-year-old male cohort with no comorbidities, 80-year-old male cohorts with no comorbidities, and 80-year-old male cohorts with significant comorbidities. INTERVENTIONS: Radical surgery and watch-and-wait approaches were studied. MAIN OUTCOME MEASURES: Incremental cost, effectiveness, and cost-effectiveness ratio over the entire lifetime of the hypothetical patient cohorts were measured. RESULTS: Watch and wait was more effective (60-year-old male cohort with no comorbidities = 0.63 quality-adjusted life-years (95% CI, 2.48-3.65 quality-adjusted life-years); 80-year-old male cohort with no comorbidities = 0.56 quality-adjusted life-years (95% CI, 0.52-1.59 quality-adjusted life-years); 80-year-old male cohort with significant comorbidities = 0.72 quality-adjusted life-years (95% CI, 0.34-1.76 quality-adjusted life-years)) and less costly (60-year-old male cohort with no comorbidities = $11,332.35 (95% CI, $668.50-$23,970.20); 80-year-old male cohort with no comorbidities = $8783.93 (95% CI, $2504.26-$21,900.66); 80-year-old male cohort with significant comorbidities = $10,206.01 (95% CI, $2762.014-$24,135.31)) independent of patient cohort age and comorbidity. Consequently, watch and wait was more cost-effective with a high degree of certainty (range, 69.6%-89.2%) at a threshold of $50,000/quality-adjusted life-year. LIMITATIONS: Long-term outcomes were derived from modeled cohorts. Analysis was performed for a United Kingdom third-party payer perspective, limiting generalizability to other healthcare contexts. CONCLUSIONS: Watch and wait is likely to be cost-effective compared with radical surgery. These findings strongly support the discussion of organ-preserving strategies with suitable patients.


Asunto(s)
Quimioradioterapia , Procedimientos Quirúrgicos del Sistema Digestivo/estadística & datos numéricos , Terapia Neoadyuvante , Años de Vida Ajustados por Calidad de Vida , Neoplasias del Recto/terapia , Espera Vigilante/estadística & datos numéricos , Anciano de 80 o más Años , Estudios de Cohortes , Comorbilidad , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Procedimientos Quirúrgicos del Sistema Digestivo/economía , Humanos , Reembolso de Seguro de Salud , Masculino , Persona de Mediana Edad , Neoplasia Residual , Neoplasias del Recto/economía , Neoplasias del Recto/epidemiología , Neoplasias del Recto/patología , Inducción de Remisión , Reino Unido , Espera Vigilante/economía
18.
Mov Disord ; 31(10): 1567-1570, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27324838

RESUMEN

BACKGROUND: The gut is proposed as a starting point of idiopathic IPD, but the presence of α-synuclein in the IPD colon mucosa is debated. OBJECTIVES: The objective of this study was to evaluate if α-synuclein in the colon mucosa can serve as a biomarker of IPD. METHODS: Immunohistochemistry was used to locate and quantify in a blinded approach α-synuclein in the mucosa from biopsies of the right and left colon in 19 IPD patients and 8 controls. RESULTS: Total α-synuclein was present in all but 1 IPD patients and in all controls; phosphorylated α-synuclein was present in all subjects. There was no intensity difference depending on disease status. Staining of total α-synuclein was stronger in the right colon (p = .04). CONCLUSIONS: Conventional immunohistochemistry α-synuclein staining in colon mucosal biopsies cannot serve as a biomarker of idiopathic PD. These findings do not contradict the assumption of disease starting in the colon, and a colon segment-specific risk for disease initiation can still be hypothesized. © 2016 International Parkinson and Movement Disorder Society.


Asunto(s)
Colon/metabolismo , Mucosa Intestinal/metabolismo , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Anciano , Biomarcadores/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Eur J Immunol ; 44(1): 69-79, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24114780

RESUMEN

Immunotherapies that augment antitumor T cells have had recent success for treating patients with cancer. Here we examined whether tumor-specific CD4(+) T cells enhance CD8(+) T-cell adoptive immunotherapy in a lymphopenic environment. Our model employed physiological doses of tyrosinase-related protein 1-specific CD4(+) transgenic T cells-CD4(+) T cells and pmel-CD8(+) T cells that when transferred individually were subtherapeutic; however, when transferred together provided significant (p ≤ 0.001) therapeutic efficacy. Therapeutic efficacy correlated with increased numbers of effector and memory CD8(+) T cells with tumor-specific cytokine expression. When combined with CD4(+) T cells, transfer of total (naïve and effector) or effector CD8(+) T cells were highly effective, suggesting CD4(+) T cells can help mediate therapeutic effects by maintaining function of activated CD8(+) T cells. In addition, CD4(+) T cells had a pronounced effect in the early posttransfer period, as their elimination within the first 3 days significantly (p < 0.001) reduced therapeutic efficacy. The CD8(+) T cells recovered from mice treated with both CD8(+) and CD4(+) T cells had decreased expression of PD-1 and PD-1-blockade enhanced the therapeutic efficacy of pmel-CD8 alone, suggesting that CD4(+) T cells help reduce CD8(+) T-cell exhaustion. These data support combining immunotherapies that elicit both tumor-specific CD4(+) and CD8(+) T cells for treatment of patients with cancer.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunoterapia Adoptiva/métodos , Melanoma Experimental/inmunología , Melanoma Experimental/terapia , Animales , Antígenos de Neoplasias/inmunología , Linfocitos T CD4-Positivos/trasplante , Linfocitos T CD8-positivos/trasplante , Vacunas contra el Cáncer/inmunología , Comunicación Celular , Microambiente Celular , Citotoxicidad Inmunológica , Femenino , Memoria Inmunológica , Inmunoterapia Adoptiva/tendencias , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Noqueados , Ratones Transgénicos , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/metabolismo
20.
J Immunol ; 190(9): 4899-909, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23536636

RESUMEN

Recurrent solid malignancies are often refractory to standard therapies. Although adoptive T cell transfer may benefit select individuals, the majority of patients succumb to their disease. To address this important clinical dilemma, we developed a mouse melanoma model in which initial regression of advanced disease was followed by tumor recurrence. During recurrence, Foxp3(+) tumor-specific CD4(+) T cells became PD-1(+) and represented >60% of the tumor-specific CD4(+) T cells in the host. Concomitantly, tumor-specific CD4(+) T effector cells showed traits of chronic exhaustion, as evidenced by their high expression of the PD-1, TIM-3, 2B4, TIGIT, and LAG-3 inhibitory molecules. Although blockade of the PD-1/PD-L1 pathway with anti-PD-L1 Abs or depletion of tumor-specific regulatory T cells (Tregs) alone failed to reverse tumor recurrence, the combination of PD-L1 blockade with tumor-specific Treg depletion effectively mediated disease regression. Furthermore, blockade with a combination of anti-PD-L1 and anti-LAG-3 Abs overcame the requirement to deplete tumor-specific Tregs. In contrast, successful treatment of primary melanoma with adoptive cell therapy required only Treg depletion or Ab therapy, underscoring the differences in the characteristics of treatment between primary and relapsing cancer. These data highlight the need for preclinical development of combined immunotherapy approaches specifically targeting recurrent disease.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Melanoma Experimental/inmunología , Recurrencia Local de Neoplasia/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD/inmunología , Antígenos CD/metabolismo , Antígenos de Diferenciación/inmunología , Antígenos de Diferenciación/metabolismo , Proteínas Reguladoras de la Apoptosis/inmunología , Proteínas Reguladoras de la Apoptosis/metabolismo , Antígeno B7-H1/inmunología , Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Línea Celular Tumoral , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/inmunología , Factores de Transcripción Forkhead/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Receptor de Muerte Celular Programada 1 , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Proteína del Gen 3 de Activación de Linfocitos
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