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1.
Cell ; 185(20): 3753-3769.e18, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36179668

RESUMEN

Interactions between angiogenesis and neurogenesis regulate embryonic brain development. However, a comprehensive understanding of the stages of vascular cell maturation is lacking, especially in the prenatal human brain. Using fluorescence-activated cell sorting, single-cell transcriptomics, and histological and ultrastructural analyses, we show that an ensemble of endothelial and mural cell subtypes tile the brain vasculature during the second trimester. These vascular cells follow distinct developmental trajectories and utilize diverse signaling mechanisms, including collagen, laminin, and midkine, to facilitate cell-cell communication and maturation. Interestingly, our results reveal that tip cells, a subtype of endothelial cells, are highly enriched near the ventricular zone, the site of active neurogenesis. Consistent with these observations, prenatal vascular cells transplanted into cortical organoids exhibit restricted lineage potential that favors tip cells, promotes neurogenesis, and reduces cellular stress. Together, our results uncover important mechanisms into vascular maturation during this critical period of human brain development.


Asunto(s)
Células Endoteliales , Neovascularización Fisiológica , Encéfalo , Colágeno , Humanos , Laminina , Midkina , Neovascularización Patológica/patología , Neovascularización Fisiológica/fisiología , Pericitos
2.
Cell ; 165(4): 921-35, 2016 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-27114033

RESUMEN

Microglia maintain homeostasis in the brain, but whether aberrant microglial activation can cause neurodegeneration remains controversial. Here, we use transcriptome profiling to demonstrate that deficiency in frontotemporal dementia (FTD) gene progranulin (Grn) leads to an age-dependent, progressive upregulation of lysosomal and innate immunity genes, increased complement production, and enhanced synaptic pruning in microglia. During aging, Grn(-/-) mice show profound microglia infiltration and preferential elimination of inhibitory synapses in the ventral thalamus, which lead to hyperexcitability in the thalamocortical circuits and obsessive-compulsive disorder (OCD)-like grooming behaviors. Remarkably, deleting C1qa gene significantly reduces synaptic pruning by Grn(-/-) microglia and mitigates neurodegeneration, behavioral phenotypes, and premature mortality in Grn(-/-) mice. Together, our results uncover a previously unrecognized role of progranulin in suppressing aberrant microglia activation during aging. These results represent an important conceptual advance that complement activation and microglia-mediated synaptic pruning are major drivers, rather than consequences, of neurodegeneration caused by progranulin deficiency.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Activación de Complemento , Complemento C1q/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Microglía/metabolismo , Envejecimiento/inmunología , Animales , Líquido Cefalorraquídeo , Complemento C1q/genética , Demencia Frontotemporal/genética , Demencia Frontotemporal/metabolismo , Granulinas , Humanos , Inmunidad Innata , Péptidos y Proteínas de Señalización Intercelular/deficiencia , Péptidos y Proteínas de Señalización Intercelular/genética , Lisosomas/metabolismo , Redes y Vías Metabólicas , Ratones , Trastorno Obsesivo Compulsivo/genética , Trastorno Obsesivo Compulsivo/metabolismo , Progranulinas , Sinapsis/metabolismo , Tálamo/metabolismo
3.
Nature ; 626(8001): 1056-1065, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38122823

RESUMEN

The temporal lobe of the human brain contains the entorhinal cortex (EC). This region of the brain is a highly interconnected integrative hub for sensory and spatial information; it also has a key role in episodic memory formation and is the main source of cortical hippocampal inputs1-4. The human EC continues to develop during childhood5, but neurogenesis and neuronal migration to the EC are widely considered to be complete by birth. Here we show that the human temporal lobe contains many young neurons migrating into the postnatal EC and adjacent regions, with a large tangential stream persisting until the age of around one year and radial dispersal continuing until around two to three years of age. By contrast, we found no equivalent postnatal migration in rhesus macaques (Macaca mulatta). Immunostaining and single-nucleus RNA sequencing of ganglionic eminence germinal zones, the EC stream and the postnatal EC revealed that most migrating cells in the EC stream are derived from the caudal ganglionic eminence and become LAMP5+RELN+ inhibitory interneurons. These late-arriving interneurons could continue to shape the processing of sensory and spatial information well into postnatal life, when children are actively interacting with their environment. The EC is one of the first regions of the brain to be affected in Alzheimer's disease, and previous work has linked cognitive decline to the loss of LAMP5+RELN+ cells6,7. Our investigation reveals that many of these cells arrive in the EC through a major postnatal migratory stream in early childhood.


Asunto(s)
Movimiento Celular , Neuronas , Lóbulo Temporal , Animales , Preescolar , Humanos , Lactante , Corteza Entorrinal/citología , Corteza Entorrinal/fisiología , Eminencia Ganglionar/citología , Interneuronas/citología , Interneuronas/fisiología , Macaca mulatta , Neuronas/citología , Neuronas/fisiología , Análisis de Expresión Génica de una Sola Célula , Lóbulo Temporal/citología , Lóbulo Temporal/crecimiento & desarrollo
4.
Nature ; 629(8012): 704-709, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693257

RESUMEN

Choline is an essential nutrient that the human body needs in vast quantities for cell membrane synthesis, epigenetic modification and neurotransmission. The brain has a particularly high demand for choline, but how it enters the brain remains unknown1-3. The major facilitator superfamily transporter FLVCR1 (also known as MFSD7B or SLC49A1) was recently determined to be a choline transporter but is not highly expressed at the blood-brain barrier, whereas the related protein FLVCR2 (also known as MFSD7C or SLC49A2) is expressed in endothelial cells at the blood-brain barrier4-7. Previous studies have shown that mutations in human Flvcr2 cause cerebral vascular abnormalities, hydrocephalus and embryonic lethality, but the physiological role of FLVCR2 is unknown4,5. Here we demonstrate both in vivo and in vitro that FLVCR2 is a BBB choline transporter and is responsible for the majority of choline uptake into the brain. We also determine the structures of choline-bound FLVCR2 in both inward-facing and outward-facing states using cryo-electron microscopy. These results reveal how the brain obtains choline and provide molecular-level insights into how FLVCR2 binds choline in an aromatic cage and mediates its uptake. Our work could provide a novel framework for the targeted delivery of therapeutic agents into the brain.


Asunto(s)
Encéfalo , Colina , Proteínas de Transporte de Membrana , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Transporte Biológico , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Colina/metabolismo , Microscopía por Crioelectrón , Técnicas In Vitro , Proteínas de Transporte de Membrana/química , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Transporte de Membrana/ultraestructura , Modelos Moleculares
5.
Nature ; 626(7998): 435-442, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38109936

RESUMEN

Many peptide hormones form an α-helix on binding their receptors1-4, and sensitive methods for their detection could contribute to better clinical management of disease5. De novo protein design can now generate binders with high affinity and specificity to structured proteins6,7. However, the design of interactions between proteins and short peptides with helical propensity is an unmet challenge. Here we describe parametric generation and deep learning-based methods for designing proteins to address this challenge. We show that by extending RFdiffusion8 to enable binder design to flexible targets, and to refining input structure models by successive noising and denoising (partial diffusion), picomolar-affinity binders can be generated to helical peptide targets by either refining designs generated with other methods, or completely de novo starting from random noise distributions without any subsequent experimental optimization. The RFdiffusion designs enable the enrichment and subsequent detection of parathyroid hormone and glucagon by mass spectrometry, and the construction of bioluminescence-based protein biosensors. The ability to design binders to conformationally variable targets, and to optimize by partial diffusion both natural and designed proteins, should be broadly useful.


Asunto(s)
Diseño Asistido por Computadora , Aprendizaje Profundo , Péptidos , Proteínas , Técnicas Biosensibles , Difusión , Glucagón/química , Glucagón/metabolismo , Mediciones Luminiscentes , Espectrometría de Masas , Hormona Paratiroidea/química , Hormona Paratiroidea/metabolismo , Péptidos/química , Péptidos/metabolismo , Estructura Secundaria de Proteína , Proteínas/química , Proteínas/metabolismo , Especificidad por Sustrato , Modelos Moleculares
6.
Nature ; 622(7981): 112-119, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37704727

RESUMEN

The molecular mechanisms and evolutionary changes accompanying synapse development are still poorly understood1,2. Here we generate a cross-species proteomic map of synapse development in the human, macaque and mouse neocortex. By tracking the changes of more than 1,000 postsynaptic density (PSD) proteins from midgestation to young adulthood, we find that PSD maturation in humans separates into three major phases that are dominated by distinct pathways. Cross-species comparisons reveal that human PSDs mature about two to three times slower than those of other species and contain higher levels of Rho guanine nucleotide exchange factors (RhoGEFs) in the perinatal period. Enhancement of RhoGEF signalling in human neurons delays morphological maturation of dendritic spines and functional maturation of synapses, potentially contributing to the neotenic traits of human brain development. In addition, PSD proteins can be divided into four modules that exert stage- and cell-type-specific functions, possibly explaining their differential associations with cognitive functions and diseases. Our proteomic map of synapse development provides a blueprint for studying the molecular basis and evolutionary changes of synapse maturation.


Asunto(s)
Proteómica , Sinapsis , Adolescente , Animales , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Ratones , Adulto Joven , Cognición/fisiología , Espinas Dendríticas , Edad Gestacional , Macaca , Neuronas/metabolismo , Densidad Postsináptica/metabolismo , Factores de Intercambio de Guanina Nucleótido Rho/metabolismo , Transducción de Señal , Especificidad de la Especie , Sinapsis/metabolismo , Sinapsis/fisiología
7.
Cell ; 149(4): 899-911, 2012 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-22579290

RESUMEN

Fragile X syndrome (FXS), the leading monogenic cause of intellectual disability and autism, results from loss of function of the RNA-binding protein FMRP. Here, we show that FMRP regulates translation of neuronal nitric oxide synthase 1 (NOS1) in the developing human neocortex. Whereas NOS1 mRNA is widely expressed, NOS1 protein is transiently coexpressed with FMRP during early synaptogenesis in layer- and region-specific pyramidal neurons. These include midfetal layer 5 subcortically projecting neurons arranged into alternating columns in the prospective Broca's area and orofacial motor cortex. Human NOS1 translation is activated by FMRP via interactions with coding region binding motifs absent from mouse Nos1 mRNA, which is expressed in mouse pyramidal neurons, but not efficiently translated. Correspondingly, neocortical NOS1 protein levels are severely reduced in developing human FXS cases, but not FMRP-deficient mice. Thus, alterations in FMRP posttranscriptional regulation of NOS1 in developing neocortical circuits may contribute to cognitive dysfunction in FXS.


Asunto(s)
Corteza Cerebral/embriología , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/embriología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Animales , Corteza Cerebral/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/fisiopatología , Regulación de la Expresión Génica , Humanos , Ratones , Ratones Noqueados , Neurogénesis , Células Piramidales/metabolismo , Procesamiento Postranscripcional del ARN , Especificidad de la Especie
8.
Proc Natl Acad Sci U S A ; 121(27): e2311831121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38941274

RESUMEN

TMEM16F is a calcium-activated phospholipid scramblase and nonselective ion channel, which allows the movement of lipids bidirectionally across the plasma membrane. While the functions of TMEM16F have been extensively characterized in multiple cell types, the role of TMEM16F in the central nervous system remains largely unknown. Here, we sought to study how TMEM16F in the brain may be involved in neurodegeneration. Using a mouse model that expresses the pathological P301S human tau (PS19 mouse), we found reduced tauopathy and microgliosis in 6- to 7-mo-old PS19 mice lacking TMEM16F. Furthermore, this reduction of pathology can be recapitulated in the PS19 mice with TMEM16F removed from neurons, while removal of TMEM16F from microglia of PS19 mice did not significantly impact tauopathy at this time point. Moreover, TMEM16F mediated aberrant phosphatidylserine exposure in neurons with phospho-tau burden. These studies raise the prospect of targeting TMEM16F in neurons as a potential treatment of neurodegeneration.


Asunto(s)
Anoctaminas , Neuronas , Fosfatidilserinas , Tauopatías , Proteínas tau , Animales , Anoctaminas/metabolismo , Anoctaminas/genética , Fosfatidilserinas/metabolismo , Neuronas/metabolismo , Neuronas/patología , Proteínas tau/metabolismo , Proteínas tau/genética , Ratones , Tauopatías/metabolismo , Tauopatías/patología , Humanos , Microglía/metabolismo , Microglía/patología , Fosforilación , Ratones Transgénicos , Modelos Animales de Enfermedad , Proteínas de Transferencia de Fosfolípidos/metabolismo , Proteínas de Transferencia de Fosfolípidos/genética , Encéfalo/metabolismo , Encéfalo/patología , Ratones Noqueados
9.
Nature ; 588(7838): 459-465, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32866962

RESUMEN

Aberrant aggregation of the RNA-binding protein TDP-43 in neurons is a hallmark of frontotemporal lobar degeneration caused by haploinsufficiency in the gene encoding progranulin1,2. However, the mechanism leading to TDP-43 proteinopathy remains unclear. Here we use single-nucleus RNA sequencing to show that progranulin deficiency promotes microglial transition from a homeostatic to a disease-specific state that causes endolysosomal dysfunction and neurodegeneration in mice. These defects persist even when Grn-/- microglia are cultured ex vivo. In addition, single-nucleus RNA sequencing reveals selective loss of excitatory neurons at disease end-stage, which is characterized by prominent nuclear and cytoplasmic TDP-43 granules and nuclear pore defects. Remarkably, conditioned media from Grn-/- microglia are sufficient to promote TDP-43 granule formation, nuclear pore defects and cell death in excitatory neurons via the complement activation pathway. Consistent with these results, deletion of the genes encoding C1qa and C3 mitigates microglial toxicity and rescues TDP-43 proteinopathy and neurodegeneration. These results uncover previously unappreciated contributions of chronic microglial toxicity to TDP-43 proteinopathy during neurodegeneration.


Asunto(s)
Microglía/metabolismo , Microglía/patología , Neuronas/metabolismo , Neuronas/patología , Progranulinas/deficiencia , Proteinopatías TDP-43/metabolismo , Proteinopatías TDP-43/patología , Envejecimiento/genética , Envejecimiento/patología , Animales , Núcleo Celular/genética , Núcleo Celular/patología , Activación de Complemento/efectos de los fármacos , Activación de Complemento/inmunología , Complemento C1q/antagonistas & inhibidores , Complemento C1q/inmunología , Complemento C3b/antagonistas & inhibidores , Complemento C3b/inmunología , Medios de Cultivo Condicionados/química , Medios de Cultivo Condicionados/farmacología , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Poro Nuclear/metabolismo , Poro Nuclear/patología , Progranulinas/genética , RNA-Seq , Análisis de la Célula Individual , Proteinopatías TDP-43/tratamiento farmacológico , Proteinopatías TDP-43/genética , Tálamo/metabolismo , Tálamo/patología , Transcriptoma
10.
Genes Dev ; 31(12): 1243-1256, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28747430

RESUMEN

Ferredoxin reductase (FDXR), a target of p53, modulates p53-dependent apoptosis and is necessary for steroidogenesis and biogenesis of iron-sulfur clusters. To determine the biological function of FDXR, we generated a Fdxr-deficient mouse model and found that loss of Fdxr led to embryonic lethality potentially due to iron overload in developing embryos. Interestingly, mice heterozygous in Fdxr had a short life span and were prone to spontaneous tumors and liver abnormalities, including steatosis, hepatitis, and hepatocellular carcinoma. We also found that FDXR was necessary for mitochondrial iron homeostasis and proper expression of several master regulators of iron metabolism, including iron regulatory protein 2 (IRP2). Surprisingly, we found that p53 mRNA translation was suppressed by FDXR deficiency via IRP2. Moreover, we found that the signal from FDXR to iron homeostasis and the p53 pathway was transduced by ferredoxin 2, a substrate of FDXR. Finally, we found that p53 played a role in iron homeostasis and was required for FDXR-mediated iron metabolism. Together, we conclude that FDXR and p53 are mutually regulated and that the FDXR-p53 loop is critical for tumor suppression via iron homeostasis.


Asunto(s)
Ferredoxina-NADP Reductasa/metabolismo , Homeostasis/genética , Proteína 2 Reguladora de Hierro/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Modelos Animales de Enfermedad , Desarrollo Embrionario/genética , Ferredoxina-NADP Reductasa/genética , Regulación de la Expresión Génica/genética , Células HCT116 , Células Hep G2 , Humanos , Hierro/metabolismo , Proteína 2 Reguladora de Hierro/genética , Hepatopatías/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias/genética , Biosíntesis de Proteínas , Proteína p53 Supresora de Tumor/genética
11.
J Proteome Res ; 23(6): 2112-2123, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38690632

RESUMEN

Diel rhythms are observed across taxa and are important for maintaining synchrony between the environment and organismal physiology. A striking example of this is the diel vertical migration undertaken by zooplankton, some of which, such as the 5 mm-long copepod Pleuromamma xiphias (P. xiphias), migrate hundreds of meters daily between the surface ocean and deeper waters. Some of the molecular pathways that underlie the expressed phenotype at different stages of this migration are entrained by environmental variables (e.g., day length and food availability), while others are regulated by internal clocks. We identified a series of proteomic biomarkers that vary across ocean DVM and applied them to copepods incubated in 24 h of darkness to assess circadian control. The dark-incubated copepods shared some proteomic similarities to the ocean-caught copepods (i.e., increased abundance of carbohydrate metabolism proteins at night). Shipboard-incubated copepods demonstrated a clearer distinction between night and day proteomic profiles, and more proteins were differentially abundant than in the in situ copepods, even in the absence of the photoperiod and other environmental cues. This pattern suggests that there is a canalization of rhythmic diel physiology in P. xiphias that reflects likely circadian clock control over diverse molecular pathways.


Asunto(s)
Migración Animal , Ritmo Circadiano , Copépodos , Proteómica , Copépodos/fisiología , Animales , Ritmo Circadiano/fisiología , Migración Animal/fisiología , Proteómica/métodos , Proteoma/metabolismo , Proteoma/análisis , Oscuridad
12.
Glia ; 72(9): 1663-1673, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924630

RESUMEN

Perinatal white matter injury (WMI) is the leading cause of long-term neurological morbidity in infants born preterm. Neuroinflammation during a critical window of early brain development plays a key role in WMI disease pathogenesis. The mechanisms linking inflammation with the long-term myelination failure that characterizes WMI, however, remain unknown. Here, we investigate the role of astrocyte reactivity in WMI. In an experimental mouse model of WMI, we demonstrate that WMI disease outcomes are improved in mutant mice lacking secretion of inflammatory molecules TNF-α, IL-1α, and C1q known, in addition to other roles, to induce the formation of a neuroinflammatory reactive astrocyte substate. We show that astrocytes express molecular signatures of the neuroinflammatory reactive astrocyte substate in both our WMI mouse model and human tissue affected by WMI, and that this gene expression pattern is dampened in injured mutant mice. Our data provide evidence that a neuroinflammatory reactive astrocyte substate correlates with adverse WMI disease outcomes, thus highlighting the need for further investigation of these cells as potential causal players in WMI pathology.


Asunto(s)
Animales Recién Nacidos , Astrocitos , Sustancia Blanca , Animales , Astrocitos/metabolismo , Astrocitos/patología , Sustancia Blanca/patología , Sustancia Blanca/metabolismo , Ratones , Humanos , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/metabolismo , Ratones Endogámicos C57BL , Femenino , Modelos Animales de Enfermedad , Ratones Noqueados , Recién Nacido
13.
BMC Cancer ; 24(1): 233, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373988

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) constitutes one of the most common types of human cancers and often metastasizes to lymph nodes. Platinum-based chemotherapeutic drugs are commonly used for treatment of a wide range of cancers, including HNSCC. Its mode of action relies on its ability to impede DNA repair mechanisms, inducing apoptosis in cancer cells. However, due to acquired resistance and toxic side-effects, researchers have been focusing on developing novel combinational therapeutic strategies to overcome cisplatin resistance. In the current study, we identified p90RSK, an ERK1/2 downstream target, as a key mediator and a targetable signaling node against cisplatin resistance. Our results strongly support the role of p90RSK in cisplatin resistance and identify the combination of p90RSK inhibitor, BI-D1870, with cisplatin as a novel therapeutic strategy to overcome cisplatin resistance. In addition, we have identified TMEM16A expression as a potential upstream regulator of p90RSK through the ERK pathway and a biomarker of response to p90RSK targeted therapy in the context of cisplatin resistance.


Asunto(s)
Antineoplásicos , Neoplasias de Cabeza y Cuello , Proteínas Quinasas S6 Ribosómicas 90-kDa , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Línea Celular Tumoral , Cisplatino/farmacología , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/genética , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Proteínas Quinasas S6 Ribosómicas 90-kDa/antagonistas & inhibidores , Anoctamina-1/genética , Anoctamina-1/metabolismo
14.
Nature ; 555(7696): 377-381, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29513649

RESUMEN

New neurons continue to be generated in the subgranular zone of the dentate gyrus of the adult mammalian hippocampus. This process has been linked to learning and memory, stress and exercise, and is thought to be altered in neurological disease. In humans, some studies have suggested that hundreds of new neurons are added to the adult dentate gyrus every day, whereas other studies find many fewer putative new neurons. Despite these discrepancies, it is generally believed that the adult human hippocampus continues to generate new neurons. Here we show that a defined population of progenitor cells does not coalesce in the subgranular zone during human fetal or postnatal development. We also find that the number of proliferating progenitors and young neurons in the dentate gyrus declines sharply during the first year of life and only a few isolated young neurons are observed by 7 and 13 years of age. In adult patients with epilepsy and healthy adults (18-77 years; n = 17 post-mortem samples from controls; n = 12 surgical resection samples from patients with epilepsy), young neurons were not detected in the dentate gyrus. In the monkey (Macaca mulatta) hippocampus, proliferation of neurons in the subgranular zone was found in early postnatal life, but this diminished during juvenile development as neurogenesis decreased. We conclude that recruitment of young neurons to the primate hippocampus decreases rapidly during the first years of life, and that neurogenesis in the dentate gyrus does not continue, or is extremely rare, in adult humans. The early decline in hippocampal neurogenesis raises questions about how the function of the dentate gyrus differs between humans and other species in which adult hippocampal neurogenesis is preserved.


Asunto(s)
Hipocampo/citología , Neurogénesis , Neuronas/citología , Adolescente , Adulto , Anciano , Animales , Animales Recién Nacidos , Recuento de Células , Proliferación Celular , Niño , Preescolar , Giro Dentado/citología , Giro Dentado/embriología , Epilepsia/patología , Femenino , Desarrollo Fetal , Voluntarios Sanos , Hipocampo/anatomía & histología , Hipocampo/embriología , Humanos , Lactante , Macaca mulatta , Masculino , Persona de Mediana Edad , Células-Madre Neurales/citología , Adulto Joven
15.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34725257

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections elicit both humoral and cellular immune responses. For the prevention and treatment of COVID-19, the disease caused by SARS-CoV-2, it has become increasingly apparent that T cell responses are equally if not more important than humoral responses in mediating recovery and immune protection. One major challenge in developing T cell-based therapies for infectious and malignant diseases has been the identification of immunogenic epitopes that can elicit a meaningful T cell response. Traditionally, this has been achieved using sophisticated in silico methods to predict putative epitopes deduced from binding affinities. Our studies find that, in contrast to current convention, "immunodominant" SARS-CoV-2 peptides defined by such in silico methods often fail to elicit T cell responses recognizing naturally presented SARS-CoV-2 epitopes. We postulated that immunogenic epitopes for SARS-CoV-2 are best defined empirically by directly analyzing peptides eluted from the naturally processed peptide-major histocompatibility complex (MHC) and then validating immunogenicity by determining whether such peptides can elicit T cells recognizing SARS-CoV-2 antigen-expressing cells. Using a tandem mass spectrometry approach, we identified epitopes derived from not only structural but also nonstructural genes in regions highly conserved among SARS-CoV-2 strains, including recently recognized variants. Finally, there are no reported T cell receptor-engineered T cell technology that can redirect T cell specificity to recognize and kill SARS-CoV-2 target cells. We report here several SARS-CoV-2 epitopes defined by mass spectrometric analysis of MHC-eluted peptides, provide empiric evidence for their immunogenicity, and demonstrate engineered TCR-redirected killing.


Asunto(s)
COVID-19/inmunología , Epítopos de Linfocito T/aislamiento & purificación , Epítopos/aislamiento & purificación , Espectrometría de Masas/métodos , Receptores de Antígenos de Linfocitos T/inmunología , SARS-CoV-2 , Linfocitos T CD8-positivos , Línea Celular , Epítopos/genética , Epítopos de Linfocito T/inmunología , Humanos , Complejo Mayor de Histocompatibilidad , Péptidos , Receptores de Antígenos de Linfocitos T/genética , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología
16.
Genet Med ; 25(1): 27-36, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36399131

RESUMEN

PURPOSE: The study aimed to describe central nervous system (CNS) progression in patients with infantile-onset Pompe disease (IOPD) and explore the potential clinical impact and predictors. METHODS: Patients with IOPD treated with enzyme replacement therapy were longitudinally followed with brain magnetic resonance imaging (MRI) and evaluation for IQ scores from 2004 to 2021. Investigation of CNS involvement focused on white matter (WM) abnormalities and was quantified using a scoring system for metachromatic leukodystrophy. MRI scores were correlated with plasma neurofilament light chain (NfL) concentration and IQ scores. RESULTS: A total of 19 patients who started enzyme replacement therapy at a mean age of 26 days were analyzed; the median age at last examination was 12.1 (range = 1.7-19) years. MRI abnormalities were found in all patients, from supratentorial central WM to U-fibers, then to infratentorial WM, and eventually to gray matter. MRI scores progressed (n = 16) at variable rates (range = 0.8-2.7/y) and were positively correlated with age (n = 16) and negatively correlated with IQ scores (n = 8). Plasma NfL concentration was positively correlated with MRI scores (r2 = 0.8569; P < .001; n = 13). CONCLUSION: Our results suggest that the progression of CNS involvement in IOPD may be associated with neuroaxonal injury and decreased IQ scores. NfL could serve as a biomarker for CNS involvement in IOPD.


Asunto(s)
Enfermedad del Almacenamiento de Glucógeno Tipo II , Sustancia Blanca , Humanos , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Enfermedad del Almacenamiento de Glucógeno Tipo II/patología , Sustancia Blanca/diagnóstico por imagen , Filamentos Intermedios , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Biomarcadores
17.
Nat Immunol ; 12(12): 1184-93, 2011 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-22019834

RESUMEN

Dendritic cells (DCs), which are known to support immune activation during infection, may also regulate immune homeostasis in resting animals. Here we show that mice lacking the ubiquitin-editing molecule A20 specifically in DCs spontaneously showed DC activation and population expansion of activated T cells. Analysis of DC-specific epistasis in compound mice lacking both A20 and the signaling adaptor MyD88 specifically in DCs showed that A20 restricted both MyD88-independent signals, which drive activation of DCs and T cells, and MyD88-dependent signals, which drive population expansion of T cells. In addition, mice lacking A20 specifically in DCs spontaneously developed lymphocyte-dependent colitis, seronegative ankylosing arthritis and enthesitis, conditions stereotypical of human inflammatory bowel disease (IBD). Our findings indicate that DCs need A20 to preserve immune quiescence and suggest that A20-dependent DC functions may underlie IBD and IBD-associated arthritides.


Asunto(s)
Colitis/inmunología , Proteínas de Unión al ADN/genética , Células Dendríticas/inmunología , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Espondilitis Anquilosante/inmunología , Ubiquitina-Proteína Ligasas/genética , Animales , Colitis/patología , Colitis/prevención & control , Enfermedad de Crohn/genética , Cisteína Endopeptidasas , Proteínas de Unión al ADN/metabolismo , Células Dendríticas/metabolismo , Predisposición Genética a la Enfermedad , Homeostasis/inmunología , Humanos , Enfermedades Linfáticas/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor 88 de Diferenciación Mieloide/metabolismo , Proteínas Nucleares/genética , Polimorfismo de Nucleótido Simple , Transducción de Señal , Esplenomegalia/genética , Espondilitis Anquilosante/patología , Espondilitis Anquilosante/prevención & control , Linfocitos T/inmunología , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa , Ubiquitina-Proteína Ligasas/metabolismo
18.
World J Urol ; 41(12): 3575-3583, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924334

RESUMEN

PURPOSE: The impact of body mass index (BMI) on patients with upper urinary tract urothelial carcinoma (UTUC) undergoing radical nephroureterectomy (RNU) is controversial. Increasing evidence suggests an age-dependent relationship between obesity and outcomes for some solid organ tumors. Herein, we aimed to assess the prognostic value of preoperative BMI in UTUC patients treated with RNU in Taiwan. METHODS: This was a retrospective single-center study of 468 UTUC patients undergoing RNU during January 2010-December 2017, with preoperative BMI classification and subgroup analysis based on ages of < or ≥ 70 years. All UTUC patients underwent RNU and bladder cuff excision. Overall survival (OS), cancer-specific survival, and disease-free survival (DFS) were analyzed. Fisher's exact test, Mann-Whitney U test, Kaplan-Meier method, and Cox regression model were used for data analysis. RESULTS: The median follow-up duration was 36 months. Patients with higher versus lower BMI (cutoff: 25 kg/m2) showed no differences in OS; older patients had poor OS (hazard ratio [HR] 1.74; 95% confidence interval [CI] 1.24-2.40; p < 0.001). Older age was an independent predictor of poor OS in multivariate Cox regression analysis (p = 0.001). Younger patients with higher BMI (p = 0.02) had better DFS than older patients with no BMI-related survival differences. Higher BMI was an independent predictor of favorable DFS in younger patients in multivariate Cox regression analysis (HR, 0.53; 95% CI 0.28-0.99; p = 0.043). CONCLUSION: Younger UTUC patients with higher BMI were independently associated with a favorable DFS.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias Renales , Neoplasias Ureterales , Neoplasias de la Vejiga Urinaria , Neoplasias Urológicas , Humanos , Nefroureterectomía , Carcinoma de Células Transicionales/patología , Índice de Masa Corporal , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/cirugía , Neoplasias Ureterales/cirugía , Pronóstico , Neoplasias Renales/cirugía , Pelvis Renal/patología , Neoplasias Urológicas/patología
19.
Brain ; 145(11): 4080-4096, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-35731122

RESUMEN

Focal anterior temporal lobe degeneration often preferentially affects the left or right hemisphere. While patients with left-predominant anterior temporal lobe atrophy show severe anomia and verbal semantic deficits and meet criteria for semantic variant primary progressive aphasia and semantic dementia, patients with early right anterior temporal lobe atrophy are more difficult to diagnose as their symptoms are less well understood. Focal right anterior temporal lobe atrophy is associated with prominent emotional and behavioural changes, and patients often meet, or go on to meet, criteria for behavioural variant frontotemporal dementia. Uncertainty around early symptoms and absence of an overarching clinico-anatomical framework continue to hinder proper diagnosis and care of patients with right anterior temporal lobe disease. Here, we examine a large, well-characterized, longitudinal cohort of patients with right anterior temporal lobe-predominant degeneration and propose new criteria and nosology. We identified individuals from our database with a clinical diagnosis of behavioural variant frontotemporal dementia or semantic variant primary progressive aphasia and a structural MRI (n = 478). On the basis of neuroimaging criteria, we defined three patient groups: right anterior temporal lobe-predominant atrophy with relative sparing of the frontal lobes (n = 46), frontal-predominant atrophy with relative sparing of the right anterior temporal lobe (n = 79) and left-predominant anterior temporal lobe-predominant atrophy with relative sparing of the frontal lobes (n = 75). We compared the clinical, neuropsychological, genetic and pathological profiles of these groups. In the right anterior temporal lobe-predominant group, the earliest symptoms were loss of empathy (27%), person-specific semantic impairment (23%) and complex compulsions and rigid thought process (18%). On testing, this group exhibited greater impairments in Emotional Theory of Mind, recognition of famous people (from names and faces) and facial affect naming (despite preserved face perception) than the frontal- and left-predominant anterior temporal lobe-predominant groups. The clinical symptoms in the first 3 years of the disease alone were highly sensitive (81%) and specific (84%) differentiating right anterior temporal lobe-predominant from frontal-predominant groups. Frontotemporal lobar degeneration-transactive response DNA binding protein (84%) was the most common pathology of the right anterior temporal lobe-predominant group. Right anterior temporal lobe-predominant degeneration is characterized by early loss of empathy and person-specific knowledge, deficits that are caused by progressive decline in semantic memory for concepts of socioemotional relevance. Guided by our results, we outline new diagnostic criteria and propose the name, 'semantic behavioural variant frontotemporal dementia', which highlights the underlying cognitive mechanism and the predominant symptomatology. These diagnostic criteria will facilitate early identification and care of patients with early, focal right anterior temporal lobe degeneration as well as in vivo prediction of frontotemporal lobar degeneration-transactive response DNA binding protein pathology.


Asunto(s)
Afasia Progresiva Primaria , Demencia Frontotemporal , Degeneración Lobar Frontotemporal , Humanos , Demencia Frontotemporal/patología , Semántica , Degeneración Lobar Frontotemporal/diagnóstico por imagen , Degeneración Lobar Frontotemporal/patología , Atrofia , Imagen por Resonancia Magnética , Afasia Progresiva Primaria/diagnóstico por imagen , Afasia Progresiva Primaria/patología , Proteínas de Unión al ADN , Pruebas Neuropsicológicas
20.
BMC Cardiovasc Disord ; 23(1): 158, 2023 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973668

RESUMEN

BACKGROUND: Coronary artery calcification (CAC) burden assessed by Agatston score (AS) is currently recommended to stratify patients at risk for future acute coronary syndrome (ACS). Besides the CAC burden, the biostructure of CAC may also play a vital role in the vulnerability of CAC, which CT radiomics could reveal. Propensity-score matching of the traditional risk factors and CAC burden between the ACS and asymptomatic groups could radically remove biases and allow the exploration of characteristic features of CAC in ACS. METHODS: We retrospectively identified 77 patients with ACS who had a CAC scan before percutaneous coronary intervention between 2016 and 2019. These 77 patients were one-to-two propensity-score matched for traditional risk factors of ACS and AS ranks to select 154 subjects from 2890 asymptomatic subjects. A validation cohort of 30 subjects was also enrolled. Radiomics features of each plaque were extracted and averaged in each person. Conditional logistic regression and area-under-curve analysis were used for statistical analysis. RESULTS: A higher number of coronary segments involved, lower mean, median, first quartile, and standard deviation of attenuation, and increased kurtosis of attenuation of CAC were associated with the ACS group compared to the control group (p < 0.05 for all). Multivariable analysis showed that the lower median attenuation (OR = 0.969, p < 0.001) and higher Kurtosis (OR = 18.7, p < 0.001) were associated with the ACS group. The median attenuation and kurtosis significantly increase across AS ranks 1 to 4 (p = 0.001). The AUC of kurtosis (0.727) and median attenuation (0.66) were both significantly higher than that of the standard AS (AUC = 0.502) and the number of TRF (AUC = 0.537). The best cut-off of kurtosis at 2.74 yielded an accuracy of 74%, and the cut-off of median attenuation at 196 yielded an accuracy of 68%. The accuracy of kurtosis was 64%, and the accuracy of median attenuation was 55% in the validation cohort. CONCLUSION: After propensity-matching traditional risk factors and CAC burden, CT radiomics highlighted that lower median attenuation and higher kurtosis were the CAC characteristics of vulnerable plaques. These features improve the understanding of the biomechanics of CAC evolution and enhance the value of CAC scan in ACS risk assessment.


Asunto(s)
Síndrome Coronario Agudo , Enfermedad de la Arteria Coronaria , Placa Aterosclerótica , Calcificación Vascular , Humanos , Síndrome Coronario Agudo/diagnóstico por imagen , Síndrome Coronario Agudo/etiología , Síndrome Coronario Agudo/terapia , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/complicaciones , Vasos Coronarios/diagnóstico por imagen , Placa Aterosclerótica/complicaciones , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/terapia
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