RESUMEN
STING is essential for control of infections and for tumor immunosurveillance, but it can also drive pathological inflammation. STING resides on the endoplasmic reticulum (ER) and traffics following stimulation to the ERGIC/Golgi, where signaling occurs. Although STING ER exit is the rate-limiting step in STING signaling, the mechanism that drives this process is not understood. Here we identify STEEP as a positive regulator of STING signaling. STEEP was associated with STING and promoted trafficking from the ER. This was mediated through stimulation of phosphatidylinositol-3-phosphate (PtdIns(3)P) production and ER membrane curvature formation, thus inducing COPII-mediated ER-to-Golgi trafficking of STING. Depletion of STEEP impaired STING-driven gene expression in response to virus infection in brain tissue and in cells from patients with STING-associated diseases. Interestingly, STING gain-of-function mutants from patients interacted strongly with STEEP, leading to increased ER PtdIns(3)P levels and membrane curvature. Thus, STEEP enables STING signaling by promoting ER exit.
Asunto(s)
Retículo Endoplásmico/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Transducción de Señal/fisiología , Animales , Retículo Endoplásmico/inmunología , Humanos , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Proteínas de la Membrana/inmunología , Ratones , Proteínas del Tejido Nervioso/inmunología , Proteínas Nucleares , Transporte de Proteínas/fisiologíaRESUMEN
Traumatic injuries to the central nervous system (CNS) afflict millions of individuals worldwide1, yet an effective treatment remains elusive. Following such injuries, the site is populated by a multitude of peripheral immune cells, including T cells, but a comprehensive understanding of the roles and antigen specificity of these endogenous T cells at the injury site has been lacking. This gap has impeded the development of immune-mediated cellular therapies for CNS injuries. Here, using single-cell RNA sequencing, we demonstrated the clonal expansion of mouse and human spinal cord injury-associated T cells and identified that CD4+ T cell clones in mice exhibit antigen specificity towards self-peptides of myelin and neuronal proteins. Leveraging mRNA-based T cell receptor (TCR) reconstitution, a strategy aimed to minimize potential adverse effects from prolonged activation of self-reactive T cells, we generated engineered transiently autoimmune T cells. These cells demonstrated notable neuroprotective efficacy in CNS injury models, in part by modulating myeloid cells via IFNγ. Our findings elucidate mechanistic insight underlying the neuroprotective function of injury-responsive T cells and pave the way for the future development of T cell therapies for CNS injuries.
Asunto(s)
Autoinmunidad , Ingeniería Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Sistema Nervioso Central , Neuroprotección , Traumatismos de la Médula Espinal , Linfocitos T , Animales , Femenino , Humanos , Masculino , Ratones , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/citología , Ingeniería Celular/métodos , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/lesiones , Células Clonales/citología , Células Clonales/inmunología , Modelos Animales de Enfermedad , Interferón gamma/inmunología , Ratones Endogámicos C57BL , Vaina de Mielina/inmunología , Células Mieloides/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Traumatismos de la Médula Espinal/terapia , Traumatismos de la Médula Espinal/inmunología , Linfocitos T/inmunología , Linfocitos T/trasplante , Análisis de Expresión Génica de una Sola Célula , Proteínas del Tejido Nervioso/inmunologíaRESUMEN
Mast cells are rare tissue-resident cells of importance to human allergies. To understand the structural basis of principle mast cell functions, we analyzed the proteome of primary human and mouse mast cells by quantitative mass spectrometry. We identified a mast-cell-specific proteome signature, indicative of a unique lineage, only distantly related to other immune cell types, including innate immune cells. Proteome comparison between human and mouse suggested evolutionary conservation of core mast cell functions. In addition to specific proteases and proteins associated with degranulation and proteoglycan biosynthesis, mast cells expressed proteins potentially involved in interactions with neurons and neurotransmitter metabolism, including cell adhesion molecules, ion channels, and G protein coupled receptors. Toward targeted cell ablation in severe allergic diseases, we used MRGPRX2 for mast cell depletion in human skin biopsies. These proteome analyses suggest a unique role of mast cells in the immune system, probably intertwined with the nervous system.
Asunto(s)
Mastocitos/citología , Mastocitos/inmunología , Animales , Biomarcadores/metabolismo , Degranulación de la Célula , Linaje de la Célula , Células Cultivadas , Tejido Conectivo/inmunología , Humanos , Inmunoterapia , Mastocitos/metabolismo , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/metabolismo , Neuroinmunomodulación , Proteoglicanos/biosíntesis , Proteoma , Receptores Acoplados a Proteínas G/inmunología , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropéptido/inmunología , Receptores de Neuropéptido/metabolismo , Piel/inmunologíaRESUMEN
In the clades of animals that diverged from the bony fish, a group of Mas-related G-protein-coupled receptors (MRGPRs) evolved that have an active role in itch and allergic signals1,2. As an MRGPR, MRGPRX2 is known to sense basic secretagogues (agents that promote secretion) and is involved in itch signals and eliciting pseudoallergic reactions3-6. MRGPRX2 has been targeted by drug development efforts to prevent the side effects induced by certain drugs or to treat allergic diseases. Here we report a set of cryo-electron microscopy structures of the MRGPRX2-Gi1 trimer in complex with polycationic compound 48/80 or with inflammatory peptides. The structures of the MRGPRX2-Gi1 complex exhibited shallow, solvent-exposed ligand-binding pockets. We identified key common structural features of MRGPRX2 and describe a consensus motif for peptidic allergens. Beneath the ligand-binding pocket, the unusual kink formation at transmembrane domain 6 (TM6) and the replacement of the general toggle switch from Trp6.48 to Gly6.48 (superscript annotations as per Ballesteros-Weinstein nomenclature) suggest a distinct activation process. We characterized the interfaces of MRGPRX2 and the Gi trimer, and mapped the residues associated with key single-nucleotide polymorphisms on both the ligand and G-protein interfaces of MRGPRX2. Collectively, our results provide a structural basis for the sensing of cationic allergens by MRGPRX2, potentially facilitating the rational design of therapies to prevent unwanted pseudoallergic reactions.
Asunto(s)
Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Prurito/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropéptido/química , Receptores de Neuropéptido/metabolismo , Alérgenos/inmunología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sitios de Unión , Secuencia de Consenso , Microscopía por Crioelectrón , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Humanos , Modelos Moleculares , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/ultraestructura , Receptores Acoplados a Proteínas G/inmunología , Receptores Acoplados a Proteínas G/ultraestructura , Receptores de Neuropéptido/inmunología , Receptores de Neuropéptido/ultraestructuraRESUMEN
RIG-I is a key mediator of antiviral immunity, able to couple detection of infection by RNA viruses to the induction of interferons. Natural RIG-I stimulatory RNAs have variously been proposed to correspond to virus genomes, virus replication intermediates, viral transcripts, or self-RNA cleaved by RNase L. However, the relative contribution of each of these RNA species to RIG-I activation and interferon induction in virus-infected cells is not known. Here, we use three approaches to identify physiological RIG-I agonists in cells infected with influenza A virus or Sendai virus. We show that RIG-I agonists are exclusively generated by the process of virus replication and correspond to full-length virus genomes. Therefore, nongenomic viral transcripts, short replication intermediates, and cleaved self-RNA do not contribute substantially to interferon induction in cells infected with these negative strand RNA viruses. Rather, single-stranded RNA viral genomes bearing 5'-triphosphates constitute the natural RIG-I agonists that trigger cell-intrinsic innate immune responses during infection.
Asunto(s)
ARN Helicasas DEAD-box/inmunología , Proteínas de la Membrana/inmunología , Proteínas del Tejido Nervioso/inmunología , Infecciones por Virus ARN/inmunología , ARN Viral/inmunología , Animales , Línea Celular , Proteína 58 DEAD Box , Perros , Humanos , Interferones/inmunología , Ratones , Virus ARN/fisiología , Receptores de Superficie Celular , Receptores Inmunológicos , Replicación ViralRESUMEN
The non-canonical NF-κB signalling cascade is essential for lymphoid organogenesis, B cell maturation, osteoclast differentiation, and inflammation in mammals1,2; dysfunction of this system is associated with human diseases, including immunological disorders and cancer3-6. Although expression of NF-κB-inducing kinase (NIK, also known as MAP3K14) is the rate-limiting step in non-canonical NF-κB pathway activation2,7, the mechanisms by which transcriptional responses are regulated remain largely unknown. Here we show that the sine oculis homeobox (SIX) homologue family transcription factors SIX1 and SIX2 are integral components of the non-canonical NF-κB signalling cascade. The developmentally silenced SIX proteins are reactivated in differentiated macrophages by NIK-mediated suppression of the ubiquitin proteasome pathway. Consequently, SIX1 and SIX2 target a subset of inflammatory gene promoters and directly inhibit the trans-activation function of the transcription factors RELA and RELB in a negative feedback circuit. In support of a physiologically pivotal role for SIX proteins in host immunity, a human SIX1 transgene suppressed inflammation and promoted the recovery of mice from endotoxic shock. In addition, SIX1 and SIX2 protected RAS/P53-driven non-small-cell lung carcinomas from inflammatory cell death induced by SMAC-mimetic chemotherapeutic agents (small-molecule activators of the non-canonical NF-κB pathway). Our findings identify a NIK-SIX signalling axis that fine-tunes inflammatory gene expression programs under both physiological and pathological conditions.
Asunto(s)
Proteínas de Homeodominio/metabolismo , Inflamación/metabolismo , FN-kappa B/deficiencia , FN-kappa B/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Animales , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Fibroblastos , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Proteínas de Homeodominio/inmunología , Humanos , Inflamación/genética , Listeria monocytogenes/inmunología , Masculino , Ratones , FN-kappa B/genética , Proteínas del Tejido Nervioso/inmunología , Regiones Promotoras Genéticas , Shigella flexneri/inmunología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factor de Transcripción ReIA/metabolismo , Factor de Transcripción ReIB/metabolismo , Quinasa de Factor Nuclear kappa BRESUMEN
GCN5L1, also known as BLOC1S1 and BLOS1, is a small intracellular protein involved in many key biological processes. Over the last decade, GCN5L1 has been implicated in the regulation of protein lysine acetylation, energy metabolism, endo-lysosomal function, and cellular immune pathways. An increasing number of published papers have used commercially-available reagents to interrogate GCN5L1 function. However, in many cases these reagents have not been rigorously validated, leading to potentially misleading results. In this report we tested several commercially-available antibodies for GCN5L1, and found that two-thirds of those available did not unambiguously detect the protein by western blot in cultured mouse cells or ex vivo liver tissue. These data suggest that previously published studies which used these unverified antibodies to measure GCN5L1 protein abundance, in the absence of other independent methods of corroboration, should be interpreted with appropriate caution.
Asunto(s)
Anticuerpos , Animales , Ratones , Anticuerpos/inmunología , Anticuerpos/metabolismo , Hígado/metabolismo , Hígado/inmunología , Ratones Noqueados , Proteínas Mitocondriales/inmunología , Proteínas del Tejido Nervioso/inmunologíaRESUMEN
PURPOSE OF REVIEW: To describe relevant advances in nonparaneoplastic autoimmune cerebellar ataxias (ACA) with neuronal antibodies. RECENT FINDINGS: Apart from metabotropic glutamate receptor 1(mGluR1) antibodies, in recent years, the number of neuronal antibodies against surface antigens in ACA has increased with the description of glutamate kainate receptor subunit 2 (GluK2) antibodies in young patients with cerebellitis. Around 20% of patients with contactin-associated protein-like 2 (CASPR2) encephalitis also present prominent cerebellar ataxia. However, isolate cerebellar ataxia is unusual (<4%). Outcome in patients with neuronal antibodies against surface antigens remains suboptimal despite the cerebellar ataxia probably is antibody-mediated.Concerning neuronal antibodies against intracellular antigens, up to 25% of patients with glutamic acid decarboxylase (GAD) antibodies present transient episodes of vertigo or diplopia that antedate the development of the ACA. There is in-vitro evidence that septin-5 is partially exposed to the membrane and the antibodies may interfere with septin-5 function. The clinical significance of the remaining antibodies against intracellular antigens remains unclear. SUMMARY: The number of antibodies against surface antigens is increasing in ACA, but the response to the immunotherapy remains suboptimal. More studies are needed to clarify the role of most of the antibodies against intracellular antigens described in these patients.
Asunto(s)
Autoanticuerpos , Ataxia Cerebelosa , Humanos , Ataxia Cerebelosa/inmunología , Autoanticuerpos/inmunología , Autoanticuerpos/sangre , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Neuronas/inmunología , Enfermedades Autoinmunes/inmunología , Proteínas del Tejido Nervioso/inmunologíaRESUMEN
A substantial number of patients recovering from acute SARS-CoV-2 infection present serious lingering symptoms, often referred to as long COVID (LC). However, a subset of these patients exhibits the most debilitating symptoms characterized by ongoing myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS). We specifically identified and studied ME/CFS patients from two independent LC cohorts, at least 12 months post the onset of acute disease, and compared them to the recovered group (R). ME/CFS patients had relatively increased neutrophils and monocytes but reduced lymphocytes. Selective T cell exhaustion with reduced naïve but increased terminal effector T cells was observed in these patients. LC was associated with elevated levels of plasma pro-inflammatory cytokines, chemokines, Galectin-9 (Gal-9), and artemin (ARTN). A defined threshold of Gal-9 and ARTN concentrations had a strong association with LC. The expansion of immunosuppressive CD71+ erythroid cells (CECs) was noted. These cells may modulate the immune response and contribute to increased ARTN concentration, which correlated with pain and cognitive impairment. Serology revealed an elevation in a variety of autoantibodies in LC. Intriguingly, we found that the frequency of 2B4+CD160+ and TIM3+CD160+ CD8+ T cells completely separated LC patients from the R group. Our further analyses using a multiple regression model revealed that the elevated frequency/levels of CD4 terminal effector, ARTN, CEC, Gal-9, CD8 terminal effector, and MCP1 but lower frequency/levels of TGF-ß and MAIT cells can distinguish LC from the R group. Our findings provide a new paradigm in the pathogenesis of ME/CFS to identify strategies for its prevention and treatment.
Asunto(s)
COVID-19 , Eritropoyesis , Síndrome de Fatiga Crónica , SARS-CoV-2 , Humanos , Síndrome de Fatiga Crónica/inmunología , Síndrome de Fatiga Crónica/sangre , COVID-19/inmunología , COVID-19/sangre , COVID-19/complicaciones , Femenino , Masculino , Persona de Mediana Edad , SARS-CoV-2/inmunología , Adulto , Eritropoyesis/inmunología , Galectinas/sangre , Galectinas/inmunología , Citocinas/sangre , Citocinas/metabolismo , Síndrome Post Agudo de COVID-19 , Inflamación/inmunología , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/sangreRESUMEN
Anti-contactin associated protein receptor 2 (CASPR2) encephalitis is a severe autoimmune encephalitis with a variable clinical phenotype including behavioral abnormalities, cognitive decline, epileptic seizures, peripheral nerve hyperexcitability and neuropathic pain. The detailed mechanisms of how CASPR2 autoantibodies lead to synaptic dysfunction and clinical symptoms are largely unknown. Aiming for analyses from the molecular to the clinical level, we isolated antibody-secreting cells from the cerebrospinal fluid of two patients with CASPR2 encephalitis. From these we cloned four anti-CASPR2 human monoclonal autoantibodies (mAbs) with strong binding to brain and peripheral nerves. All were highly hypermutated and mainly of the IgG4 subclass. Mutagenesis studies determined selective binding to the discoidin domain of CASPR2. Surface plasmon resonance revealed affinities with dissociation constants KD in the pico- to nanomolar range. CASPR2 mAbs interrupted the interaction of CASPR2 with its binding partner contactin 2 in vitro and were internalized after binding to CASPR2-expressing cells. Electrophysiological recordings of rat hippocampal slices after stereotactic injection of CASPR2 mAbs showed characteristic afterpotentials following electrical stimulation. In vivo experiments with intracerebroventricular administration of human CASPR2 mAbs into mice and rats showed EEG-recorded brain hyperexcitability but no spontaneous recurrent seizures. Behavioral assessment of infused mice showed a subtle clinical phenotype, mainly affecting sociability. Mouse brain MRI exhibited markedly reduced resting-state functional connectivity without short-term structural changes. Together, the experimental data support the direct pathogenicity of CASPR2 autoantibodies. The minimally invasive EEG and MRI techniques applied here may serve as novel objective, quantifiable tools for improved animal models, in particular for subtle neuropsychiatric phenotypes or repeated measurements.
Asunto(s)
Anticuerpos Monoclonales , Autoanticuerpos , Encefalitis , Imagen por Resonancia Magnética , Proteínas de la Membrana , Proteínas del Tejido Nervioso , Animales , Autoanticuerpos/inmunología , Autoanticuerpos/metabolismo , Ratas , Humanos , Ratones , Imagen por Resonancia Magnética/métodos , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/metabolismo , Masculino , Encefalitis/inmunología , Encefalitis/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/inmunología , Modelos Animales de Enfermedad , Femenino , Encéfalo/metabolismo , Hipocampo/metabolismo , Conducta Animal/fisiologíaRESUMEN
Host innate recognition triggers key immune responses for viral elimination. The sensing mechanism of hepatitis B virus (HBV), a DNA virus, and the subsequent downstream signaling events remain to be fully clarified. Here we found that type III but not type I interferons are predominantly induced in human primary hepatocytes in response to HBV infection, through retinoic acid-inducible gene-I (RIG-I)-mediated sensing of the 5'-ε region of HBV pregenomic RNA. In addition, RIG-I could also counteract the interaction of HBV polymerase (P protein) with the 5'-ε region in an RNA-binding dependent manner, which consistently suppressed viral replication. Liposome-mediated delivery and vector-based expression of this ε region-derived RNA in liver abolished the HBV replication in human hepatocyte-chimeric mice. These findings identify an innate-recognition mechanism by which RIG-I dually functions as an HBV sensor activating innate signaling and to counteract viral polymerase in human hepatocytes.
Asunto(s)
Productos del Gen pol/antagonistas & inhibidores , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/inmunología , Hepatocitos/fisiología , Hígado/fisiología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , ARN Viral/inmunología , Animales , Preescolar , Femenino , Células Hep G2 , Hepatocitos/trasplante , Hepatocitos/virología , Humanos , Inmunidad Innata , Interferones/metabolismo , Hígado/virología , Proteínas de la Membrana/inmunología , Ratones , Ratones SCID , Proteínas del Tejido Nervioso/inmunología , ARN Viral/genética , Receptores de Superficie Celular , Transgenes/genética , Quimera por Trasplante , Replicación Viral/genéticaRESUMEN
Synaptic ribbons are the eponymous specializations of continuously active ribbon synapses. They are primarily composed of the RIBEYE protein that consists of a unique amino-terminal A-domain and carboxy-terminal B-domain that is largely identical to the ubiquitously expressed transcriptional regulator protein CtBP2. Both RIBEYE A-domain and RIBEYE B-domain are essential for the assembly of the synaptic ribbon, as shown by previous analyses of RIBEYE knockout and knockin mice and related investigations. How exactly the synaptic ribbon is assembled from RIBEYE subunits is not yet clear. To achieve further insights into the architecture of the synaptic ribbon, we performed analytical post-embedding immunogold-electron microscopy with direct gold-labelled primary antibodies against RIBEYE A-domain and RIBEYE B-domain for improved ultrastructural resolution. With direct gold-labelled monoclonal antibodies against RIBEYE A-domain and RIBEYE B-domain, we found that both domains show a very similar localization within the synaptic ribbon of mouse photoreceptor synapses, with no obvious differential gradient between the centre and surface of the synaptic ribbon. These data favour a model of the architecture of the synaptic ribbon in which the RIBEYE A-domain and RIBEYE B-domain are located similar distances from the midline of the synaptic ribbon.
Asunto(s)
Anticuerpos Monoclonales , Sinapsis , Animales , Ratones , Sinapsis/ultraestructura , Sinapsis/metabolismo , Anticuerpos Monoclonales/inmunología , Oxidorreductasas de Alcohol/metabolismo , Oxidorreductasas de Alcohol/química , Proteínas Co-Represoras/metabolismo , Inmunohistoquímica/métodos , Dominios Proteicos , Microscopía Inmunoelectrónica/métodos , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/inmunologíaRESUMEN
Chorea is a very commonly encountered movement disorder; it has various etiologies, and it can have autoimmune, vascular, degenerative, or paraneoplastic etiology. Our patient had acute onset chorea and a strong history of smoking, which made us suspect first vascular followed by paraneoplastic cause. After ruling out common vascular and metabolic causes, his whole body positron emission tomography (PET) scan revealed a mass in the right upper lobe, a biopsy revealed a small cell carcinoma lung and a paraneoplastic panel showed antibodies positive for collapsin response mediator protein 5 antigen (CRMP-5/CV2); the patient was started on immunomodulation, chemotherapy with the variable response, he succumbed to a cardiac event after treatment.
Asunto(s)
Corea , Neoplasias Pulmonares , Humanos , Corea/etiología , Corea/diagnóstico , Masculino , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico , Proteínas del Tejido Nervioso/inmunología , Carcinoma Pulmonar de Células Pequeñas/complicaciones , Resultado Fatal , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Hidrolasas , Proteínas Asociadas a MicrotúbulosRESUMEN
Paraneoplastic neurological syndromes occur due to immune-mediated neuronal dysfunction secondary to systemic malignancy, and symptoms can usually be seen before malignancy. There are many subtypes that depend on the antibodies present or the proteins they target. Accurate epidemiological data are lacking as it is difficult to diagnose. We would like to present a case of anti-Yo antibody-associated encephalitis due to breast cancer in a 47-year-old male patient. When we searched the literature, we did not find a case of anti-Yo-associated autoimmune encephalitis due to breast adenocarcinoma in a male patient. For this reason, we find it worth presenting our case.
Asunto(s)
Adenocarcinoma , Neoplasias de la Mama Masculina , Encefalitis , Humanos , Masculino , Persona de Mediana Edad , Adenocarcinoma/complicaciones , Adenocarcinoma/inmunología , Neoplasias de la Mama Masculina/complicaciones , Neoplasias de la Mama Masculina/inmunología , Encefalitis/inmunología , Encefalitis/complicaciones , Encefalitis/etiología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Proteínas del Tejido Nervioso/inmunología , Enfermedad de Hashimoto/complicaciones , Enfermedad de Hashimoto/inmunología , Enfermedad de Hashimoto/diagnóstico , Síndromes Paraneoplásicos del Sistema Nervioso/inmunología , Síndromes Paraneoplásicos del Sistema Nervioso/etiologíaRESUMEN
Anti-N-methyl D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disorder characterized by IgG antibodies targeting NMDAR. The prevalence is remarkably higher in women and some develop the condition during pregnancy. While immunotherapies have shown good outcomes for pregnant mothers and their infants, the impact on early neurodevelopment remains elusive. This study investigates the effects of anti-NMDAR antibody on the development of primary cortical cultures. Anti-NMDAR antibody was administered to the cultures at day in vitro 5 for the following 5 days to assess dendritic branching and arbor complexity, and at day in vitro 14 for measuring the expression of brain-derived neurotrophic factor (BDNF) and synaptic proteins. Immature cultured neurons treated with anti-NMDAR antibody exhibited impaired dendritic branching and arbor complexity. Interestingly, BDNF expression was unaffected in mature neurons. Additionally, GluN1 expression, a mandatory NMDAR subunit, was significantly reduced, while no significant alterations were observed in PSD-95, gephyrin and synaptophysin expression. These findings shed light on the structural and synaptic impacts of anti-NMDAR antibody on immature neurons, providing evidence for their consequences in early neuronal development.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Dendritas , Neuronas , Receptores de N-Metil-D-Aspartato , Animales , Receptores de N-Metil-D-Aspartato/inmunología , Dendritas/efectos de los fármacos , Dendritas/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Células Cultivadas , Homólogo 4 de la Proteína Discs Large/metabolismo , Sinaptofisina/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/inmunología , Ratas , Proteínas Portadoras , Femenino , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/metabolismoRESUMEN
During immunoglobulin class-switch recombination (CSR), the cytidine deaminase AID induces double-strand breaks into transcribed, repetitive DNA elements called switch sequences. The mechanism that promotes the binding of AID specifically to switch regions remains to be elucidated. Here we used a proteomic screen with in vivo biotinylation of AID to identify the splicing regulator PTBP2 as a protein that interacts with AID. Knockdown of PTBP2 mediated by short hairpin RNA in B cells led to a decrease in binding of AID to transcribed switch regions, which resulted in considerable impairment of CSR. PTBP2 is thus an effector of CSR that promotes the binding of AID to switch-region DNA.
Asunto(s)
Citidina Desaminasa/metabolismo , ADN/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteína de Unión al Tracto de Polipirimidina/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Citidina Desaminasa/genética , Citidina Desaminasa/inmunología , ADN/genética , Cambio de Clase de Inmunoglobulina/genética , Región de Cambio de la Inmunoglobulina/genética , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Proteína de Unión al Tracto de Polipirimidina/genética , Proteína de Unión al Tracto de Polipirimidina/inmunología , Unión Proteica/genética , ARN Interferente Pequeño/genética , Activación Transcripcional/genética , Activación Transcripcional/inmunología , Transgenes/genéticaRESUMEN
Type 2 helper T cells (T(H)2) are critically involved in allergies and asthma. Here we demonstrate that extracellular matrix protein-1 (ECM1) is highly and selectively expressed in T(H)2 cells. ECM1 deficiency caused impaired T(H)2 responses and reduced allergic airway inflammation in vivo. Functional analysis demonstrated that although the T(H)2 polarization of ECM1-deficient cells was unimpaired, these cells had a defect in migration and were retained in peripheral lymphoid organs. This was associated with reduced expression of KLF2 and S1P(1). We also found that ECM1 could directly bind the interleukin-2 (IL-2) receptor to inhibit IL-2 signaling and activate S1P(1) expression. Our data identify a previously unknown function of ECM1 in regulating T(H)2 cell migration through control of KLF2 and S1P(1) expression.
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Proteínas de la Matriz Extracelular/metabolismo , Hipersensibilidad/inmunología , Proteínas del Tejido Nervioso/metabolismo , Receptores Mensajeros de Linfocitos/metabolismo , Células Th2/metabolismo , Traslado Adoptivo , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Movimiento Celular/genética , Movimiento Celular/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/inmunología , Regulación de la Expresión Génica/inmunología , Humanos , Ganglios Linfáticos/patología , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Receptores Mensajeros de Linfocitos/genética , Receptores Mensajeros de Linfocitos/inmunología , Transducción de Señal/inmunología , Células Th2/inmunología , Células Th2/patología , Transgenes/genéticaRESUMEN
OBJECTIVE: The encephalitis associated with antibodies against contactin-associated proteinlike 2 (CASPR2) is presumably antibody-mediated, but the antibody effects and whether they cause behavioral alterations are not well known. Here, we used a mouse model of patients' immunoglobulin G (IgG) transfer and super-resolution microscopy to demonstrate the antibody pathogenicity. METHODS: IgG from patients with anti-CASPR2 encephalitis or healthy controls was infused into the cerebroventricular system of mice. The levels and colocalization of CASPR2 with transient axonal glycoprotein 1 (TAG1) were determined with stimulated emission depletion microscopy (40-70µm lateral resolution). Hippocampal clusters of Kv1.1 voltage-gated potassium channels (VGKCs) and GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) were quantified with confocal microscopy. Behavioral alterations were assessed with standard behavioral paradigms. Cultured neurons were used to determine the levels of intracellular CASPR2 and TAG1 after exposure to patients' IgG. RESULTS: Infusion of patients' IgG, but not controls' IgG, caused memory impairment along with hippocampal reduction of surface CASPR2 clusters and decreased CASPR2/TAG1 colocalization. In cultured neurons, patients' IgG led to an increase of intracellular CASPR2 without affecting TAG1, suggesting selective CASPR2 internalization. Additionally, mice infused with patients' IgG showed decreased levels of Kv1.1 and GluA1 (two CASPR2-regulated proteins). All these alterations and the memory deficit reverted to normal after removing patients' IgG. INTERPRETATION: IgG from patients with anti-CASPR2 encephalitis causes reversible memory impairment, inhibits the interaction of CASPR2/TAG1, and decreases the levels of CASPR2 and related proteins (VGKC, AMPAR). These findings fulfill the postulates of antibody-mediated disease and provide a biological basis for antibody-removing treatment approaches. ANN NEUROL 2022;91:801-813.
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Autoanticuerpos , Encefalitis , Proteínas de la Membrana , Proteínas del Tejido Nervioso , Canales de Potasio con Entrada de Voltaje , Animales , Autoanticuerpos/inmunología , Contactina 2/inmunología , Encefalitis/inmunología , Humanos , Inmunoglobulina G/metabolismo , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Ratones , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/metabolismoRESUMEN
Plasmacytoid dendritic cells (PDCs) represent a unique immune cell type specialized in type I interferon (IFN) secretion in response to viral nucleic acids. The molecular control of PDC lineage specification has been poorly understood. We report that basic helix-loop-helix transcription factor (E protein) E2-2/Tcf4 is preferentially expressed in murine and human PDCs. Constitutive or inducible deletion of murine E2-2 blocked the development of PDCs but not of other lineages and abolished IFN response to unmethylated DNA. Moreover, E2-2 haploinsufficiency in mice and in human Pitt-Hopkins syndrome patients was associated with aberrant expression profile and impaired IFN response of the PDC. E2-2 directly activated multiple PDC-enriched genes, including transcription factors involved in PDC development (SpiB, Irf8) and function (Irf7). These results identify E2-2 as a specific transcriptional regulator of the PDC lineage in mice and humans and reveal a key function of E proteins in the innate immune system.
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Células Dendríticas/inmunología , Proteínas del Tejido Nervioso/inmunología , Factores de Transcripción TCF/inmunología , Adolescente , Animales , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Niño , Preescolar , Proteínas de Unión al ADN , Células Dendríticas/metabolismo , Humanos , Hiperventilación/inmunología , Inmunidad Innata , Discapacidad Intelectual/inmunología , Interferones/inmunología , Ratones , Síndrome , Factor de Transcripción 4 , Proteína 2 Similar al Factor de Transcripción 7 , Factores de TranscripciónRESUMEN
Enhancing long-term persistence while simultaneously potentiating the effector response of CD8+ T cells has been a long-standing goal in immunology to produce better vaccines and adoptive cell therapy products. NR4A3 is a transcription factor of the orphan nuclear receptor family. While it is rapidly and transiently expressed following T cell activation, its role in the early stages of T cell response is unknown. We show that NR4A3-deficient murine CD8+ T cells differentiate preferentially into memory precursor and central memory cells, but also produce more cytokines. This is explained by an early influence of NR4A3 deficiency on the memory transcriptional program and on accessibility of chromatin regions with motifs for bZIP transcription factors, which impacts the transcription of Fos/Jun target genes. Our results reveal a unique and early role for NR4A3 in programming CD8+ T cell differentiation and function. Manipulating NR4A3 activity may represent a promising strategy to improve vaccination and T cell therapy.