Publications by authors named "Thomas Ngo"

Mutations in Sonic Hedgehog (SHH) signaling pathway genes, for example, (SUFU), drive granule neuron precursors (GNP) to form medulloblastomas (MB). However, how different molecular lesions in the Shh pathway drive transformation is frequently unclear, and mutations in the cerebellum seem distinct. In this study, we show that fibroblast growth factor 5 (FGF5) signaling is integral for many infantile MB cases and that expression is uniquely upregulated in infantile MB tumors.

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N-methyl-d-aspartate (NMDA) receptor-mediated autoimmune encephalitis (NMDAR-AE) frequently results in persistent sensory-motor deficits, especially in children, yet the underlying mechanisms remain unclear. This study investigated the long-term effects of exposure to a patient-derived GluN1-specific mAb during a critical developmental period (from postnatal day 3 to day 12) in mice. We observed long-lasting sensory-motor deficits characteristic of NMDAR-AE, along with permanent changes in callosal axons within the primary somatosensory cortex (S1) in adulthood, including increased terminal branch complexity.

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Ataxia with anti-regulator of G-protein signaling 8 autoantibodies (RGS8-Abs) is an autoimmune disease recently described in four patients. The present study aimed to identify other patients with RGS8-Abs, describe their clinical features, including the link between RGS8-related autoimmune cerebellar ataxia (ACA) and cancer. Patients with RGS8-Abs were identified retrospectively in the biological collections of the French Reference Center for Paraneoplastic Neurological Syndrome and the University of California San Francisco Center for Encephalitis and Meningitis.

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Article Synopsis
  • Vitamin B12 is essential for blood cell formation and nerve insulation, and its deficiency can lead to neurological issues despite normal blood levels, as seen in a patient with symptoms like tremor and cognitive decline.
  • Researchers discovered an autoantibody against the transcobalamin receptor (CD320) that hinders vitamin B12 uptake in the brain, resulting in low levels found in cerebrospinal fluid even when blood levels appear normal.
  • The study suggests this autoimmune condition can be treated with immunosuppressive therapy and high-dose vitamin B12, and highlights the importance of recognizing how B12 transport differs in various tissues, which could improve diagnosis and treatment strategies for similar neurological disorders.
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Epileptic seizures induce aberrant neurogenesis from resident neural stem cells (NSCs) in the dentate gyrus of the adult mouse hippocampus, which has been implicated in depletion of the NSC pool and impairment of hippocampal function. However, the mechanisms regulating neurogenesis after seizures remain unknown. Here, we demonstrate that Sonic hedgehog (Shh) from mossy cells is a major source of Shh signaling activity after seizures, by which mossy cells contribute to seizure-induced neurogenesis and maintenance of the NSC pool.

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Epileptic seizures induce aberrant neurogenesis from resident neural stem cells (NSCs) in the dentate gyrus of the adult mouse hippocampus, which has been implicated in depletion of the NSC pool and impairment of hippocampal function. However, the mechanisms regulating neurogenesis after seizures remain unknown. Here we demonstrate that Shh from mossy cells is a major source of Shh signaling activity after seizures, by which mossy cells contribute to seizure-induced neurogenesis and maintenance of the NSC pool.

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Article Synopsis
  • The study focuses on the detection of anti-TRIM9 and TRIM67 autoantibodies (TRIM9/67-IgG) in patients with paraneoplastic cerebellar syndrome, aiming to determine their diagnostic value and the most effective detection methods.
  • A retrospective analysis across multiple centers found that cell-based assays (CBA) were the most sensitive method for confirming the presence of TRIM9/67-IgG, identifying it in all tested cases (100%).
  • The findings indicate that a significant majority of patients with TRIM9/67-IgG had subacute cerebellar syndrome and were often associated with underlying cancers, reinforcing the idea of these auto
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Neuroinvasive infection is the most common cause of meningoencephalitis in people living with human immunodeficiency virus (HIV), but autoimmune etiologies have been reported. We present the case of a 51-year-old man living with HIV infection with steroid-responsive meningoencephalitis whose comprehensive pathogen testing was non-diagnostic. Subsequent tissue-based immunofluorescence with acute-phase cerebrospinal fluid revealed anti-neural antibodies localizing to the axon initial segment (AIS), the node of Ranvier (NoR), and the subpial space.

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Objective: To identify the autoantigen in 2 individuals with possible seronegative paraneoplastic neuropathy.

Methods: Serum and CSF were screened by tissue-based assay and panned for candidate autoantibodies by phage display immunoprecipitation sequencing (PhIP-Seq). The candidate antigen was validated by immunostaining knockout tissue and HEK 293T cell-based assay.

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The development of autoimmune antibody panels has improved the diagnosis of paraneoplastic neurological disorders (PNDs) of the brain and spinal cord. Here, we present a case of a woman with a history of breast cancer who presented with a subacute sensory ataxia that progressed over 18 months. Her examination and diagnostic studies were consistent with a myelopathy.

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Importance: Neuropsychiatric manifestations of COVID-19 have been reported in the pediatric population.

Objective: To determine whether anti-SARS-CoV-2 and autoreactive antibodies are present in the cerebrospinal fluid (CSF) of pediatric patients with COVID-19 and subacute neuropsychiatric dysfunction.

Design, Setting, And Participants: This case series includes 3 patients with recent SARS-CoV-2 infection as confirmed by reverse transcriptase-polymerase chain reaction or IgG serology with recent exposure history who were hospitalized at the University of California, San Francisco Benioff Children's Hospital and for whom a neurology consultation was requested over a 5-month period in 2020.

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Retraction notice to: “Remission of Subacute Psychosis in a COVID-19 Patient With an Antineuronal Autoantibody After Treatment With Intravenous Immunoglobulin” by Lindsay S. McAlpine, Brooke Lifland, Joseph R. Check, Gustavo A.

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Individuals with coronavirus disease 2019 (COVID-19) frequently develop neurological symptoms, but the biological underpinnings of these phenomena are unknown. Through single-cell RNA sequencing (scRNA-seq) and cytokine analyses of cerebrospinal fluid (CSF) and blood from individuals with COVID-19 with neurological symptoms, we find compartmentalized, CNS-specific T cell activation and B cell responses. All affected individuals had CSF anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies whose target epitopes diverged from serum antibodies.

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One third of COVID-19 patients develop significant neurological symptoms, yet SARS-CoV-2 is rarely detected in central nervous system (CNS) tissue, suggesting a potential role for parainfectious processes, including neuroimmune responses. We therefore examined immune parameters in cerebrospinal fluid (CSF) and blood samples from a cohort of patients with COVID-19 and significant neurological complications. We found divergent immunological responses in the CNS compartment, including increased levels of IL-12 and IL-12-associated innate and adaptive immune cell activation.

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Neuronal progenitors in the developing forebrain undergo dynamic competence states to ensure timely generation of specific excitatory and inhibitory neuronal subtypes from distinct neurogenic niches of the dorsal and ventral forebrain, respectively. Here we show evidence of progenitor plasticity when Sonic hedgehog (SHH) signaling is left unmodulated in the embryonic neocortex of the mammalian dorsal forebrain. We found that, at early stages of corticogenesis, loss of Suppressor of Fused (Sufu), a potent inhibitor of SHH signaling, in neocortical progenitors, altered the transcriptomic landscape of male mouse embryos.

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