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The dry mass and the orientation of biomolecules can be imaged without a label by measuring their permittivity tensor (PT), which describes how biomolecules affect the phase and polarization of light. Three-dimensional (3D) imaging of PT has been challenging. We present a label-free computational microscopy technique, PT imaging (PTI), for the 3D measurement of PT. PTI encodes the invisible PT into images using oblique illumination, polarization-sensitive detection and volumetric sampling. PT is decoded from the data with a vectorial imaging model and a multi-channel inverse algorithm, assuming uniaxial symmetry in each voxel. We demonstrate high-resolution imaging of PT of isotropic beads, anisotropic glass targets, mouse brain tissue, infected cells and histology slides. PTI outperforms previous label-free imaging techniques such as vector tomography, ptychography and light-field imaging in resolving the 3D orientation and symmetry of organelles, cells and tissue. We provide open-source software and modular hardware to enable the adoption of the method.
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Algoritmos , Imagenología Tridimensional , Imagenología Tridimensional/métodos , Animales , Ratones , Encéfalo/diagnóstico por imagen , Microscopía/métodos , Programas Informáticos , Humanos , Procesamiento de Imagen Asistido por Computador/métodosRESUMEN
BACKGROUND AND OBJECTIVES: Neuromyelitis optica spectrum disorder (NMOSD) is a chronic CNS demyelinating autoimmune disorder targeting the astrocyte antigen aquaporin-4 (AQP4), typically presenting with optic neuritis, transverse myelitis, and brain syndromes. Cognitive dysfunction (CD) in NMOSD is under-recognized and poorly understood. The purpose of this study was to evaluate the prevalence and clinical variables associated with CD in NMOSD. METHODS: This observational retrospective study with longitudinal follow-up describes a clinical cohort seen in the Collaborative International Research in Clinical and Longitudinal Experience Study in NMOSD. Serial Montreal Cognitive Assessments (MoCAs) were performed upon enrollment and at 6-month intervals to evaluate longitudinal cognitive function relative to demographic and disease-related factors. We used 2-tailed t test, analysis of variance, the χ2 test, linear regression for univariable and adjusted analyses and simultaneous linear regression and mixed-effects model for multivariable analyses. RESULTS: Thirty-four percent (75/219) of patients met criteria for CD (MoCA <26); 29% (64/219) showed mild dysfunction (MoCA 20-26/30), and 5% (11/219) showed moderate (MoCA <20/30) dysfunction. Patients with less neurologic disability and lower pain scores had higher MoCA scores (95% CI 0.24-0.65 and 95% CI 0.09-0.42, respectively). Patients with at least high school education scored higher on the MoCA (95% CI 2.2-5). When comparing patients dichotomized for CD, patients never on rituximab scored higher than patients only treated with rituximab (p < 0.029). There was no significant association between annualized relapse rate, age, sex, disease duration, AQP4 serostatus or brain lesions, and CD. CD was more pronounced among Black than White patients (95% CI -2.7 to -0.7). Multivariable analysis of serial MoCA did not indicate change (p = 0.715). Descriptive analysis of serial MoCA showed 30% (45/150) of patients with worsening MoCA performance had impaired language and verbal recall. DISCUSSION: To our knowledge, this is the largest study of diverse cohort to investigate CD in patients with NMOSD. Our findings demonstrate 34% of patients with NMOSD experience mild-to-moderate CD, while 30% of patients demonstrated decline on serial testing. The substantial prevalence of CD in this pilot report highlights the need for improved and validated screening tools and comprehensive measures to investigate CD in NMOSD.
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Disfunción Cognitiva , Neuromielitis Óptica , Humanos , Neuromielitis Óptica/complicaciones , Neuromielitis Óptica/epidemiología , Prevalencia , Estudios Retrospectivos , Rituximab , Recurrencia Local de Neoplasia , Disfunción Cognitiva/epidemiología , Acuaporina 4RESUMEN
ABSTRACT: CD19 chimeric antigen receptor (CAR) T-cell therapy has proven highly effective for treating relapsed/refractory mantle cell lymphoma (MCL). However, immune effector cell-associated neurotoxicity syndrome (ICANS) remains a significant concern. This study aimed to evaluate the clinical, radiological, and laboratory correlatives associated with ICANS development after CD19 CAR T-cell therapy in patients with MCL. All patients (N = 26) who received standard-of-care brexucabtagene autoleucel until July 2022 at our institution were evaluated. Laboratory and radiographic correlatives including brain magnetic resonance imaging (MRI) and electroencephalogram (EEG) were evaluated to determine the clinical impact of ICANS. Seventeen (65%) patients experienced ICANS after treatment, with a median onset on day 6. Ten (38%) patients experienced severe (grade ≥3) ICANS. All patients with ICANS had antecedent cytokine release syndrome (CRS), but no correlation was observed between ICANS severity and CRS grade. Overall, 92% of EEGs revealed interictal changes; no patients experienced frank seizures because of ICANS. In total, 86% of patients with severe ICANS with postinfusion brain MRIs demonstrated acute neuroimaging findings not seen on pretreatment MRI. Severe ICANS was also associated with higher rates of cytopenia, coagulopathy, increased cumulative steroid exposure, and prolonged hospitalization. However, severe ICANS did not affect treatment outcomes of patients with MCL. Severe ICANS is frequently associated with a range of postinfusion brain MRI changes and abnormal EEG findings. Longer hospitalization was observed in patients with severe ICANS, especially those with abnormal acute MRI or EEG findings, but there was no discernible impact on overall treatment response and survival.
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Linfoma de Células del Manto , Síndromes de Neurotoxicidad , Humanos , Adulto , Linfoma de Células del Manto/terapia , Inmunoterapia Adoptiva/efectos adversos , Proteínas Adaptadoras Transductoras de Señales , Antígenos CD19 , Encéfalo , Síndrome de Liberación de CitoquinasRESUMEN
Multiple sclerosis (MS) is an inflammatory-demyelinating disease of the central nervous system (CNS) mediated by aberrant auto-reactive immune responses. The current immune-modulatory therapies are unable to protect and repair immune-mediated neural tissue damage. One of the therapeutic targets in MS is the sphingosine-1-phosphate (S1P) pathway which signals via sphingosine-1-phosphate receptors 1-5 (S1P1-5). S1P receptors are expressed predominantly on immune and CNS cells. Considering the potential neuroprotective properties of S1P signaling, we utilized S1P1-GFP (Green fluorescent protein) reporter mice in the cuprizone-induced demyelination model to investigate in vivo S1P - S1P1 signaling in the CNS. We observed S1P1 signaling in a subset of neural stem cells in the subventricular zone (SVZ) during demyelination. During remyelination, S1P1 signaling is expressed in oligodendrocyte progenitor cells in the SVZ and mature oligodendrocytes in the medial corpus callosum (MCC). In the cuprizone model, we did not observe S1P1 signaling in neurons and astrocytes. We also observed ß-arrestin-dependent S1P1 signaling in lymphocytes during demyelination and CNS inflammation. Our findings reveal ß-arrestin-dependent S1P1 signaling in oligodendrocyte lineage cells implying a role of S1P1 signaling in remyelination.
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Esclerosis Múltiple , Remielinización , Ratones , Animales , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/uso terapéutico , Cuprizona , Receptores de Lisoesfingolípidos/metabolismo , Receptores de Lisoesfingolípidos/uso terapéutico , Sistema Nervioso Central/metabolismo , Esclerosis Múltiple/metabolismo , Oligodendroglía/metabolismo , beta-Arrestinas/metabolismo , beta-Arrestinas/uso terapéutico , Ratones Endogámicos C57BLRESUMEN
Background: Fingolimod is a sphingosine 1-phosphate receptor modulator approved for relapsing MS. Long-term effects on the immunological profile are not fully understood. Objective: Investigate fingolimod's temporal effects on immune cell subsets, and safety outcomes. Methods: In FLUENT, a 12-month, prospective, non-randomized, open-label, phase IV study, adult participants received fingolimod 0.5â mg/day. Changes in immune cell subsets, anti-John Cunningham virus (JCV) antibody index, and serum neurofilament levels were assessed. Results: 165 fingolimod-naive and 217 participants treated for 2-12 years in routine clinical practice were enrolled. Levels of all monitored peripheral lymphocyte subsets were reduced from month 3 in fingolimod-naive participants. Greatest reductions occurred in naive and central memory CD4+ and CD8+ T cells, and in naive and memory B cells. Most lymphocyte subset levels remained stable in the continuous fingolimod group. Components of the innate immune system remained within reference ranges. No increase in JCV seropositivity was observed. No single cellular subset correlated with anti-JCV antibody index at any time point. Neurofilament levels remained within healthy adult reference limits throughout. No opportunistic infections were reported; no new or unexpected safety signals were observed. Conclusion: FLUENT provides insights into the utility of immunological profiling to evaluate therapy response and potential infection risk.
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Antígeno 2 del Estroma de la Médula Ósea/genética , Células Dendríticas/inmunología , Esclerosis Múltiple/genética , Animales , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/patología , Células Dendríticas/metabolismo , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Humanos , Ratones , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patologíaRESUMEN
Pericytes regulate the development of organ-specific characteristics of the brain vasculature such as the blood-brain barrier (BBB) and astrocytic end-feet. Whether pericytes are involved in the control of leukocyte trafficking in the adult central nervous system (CNS), a process tightly regulated by CNS vasculature, remains elusive. Using adult pericyte-deficient mice (Pdgfbret/ret ), we show that pericytes limit leukocyte infiltration into the CNS during homeostasis and autoimmune neuroinflammation. The permissiveness of the vasculature toward leukocyte trafficking in Pdgfbret/ret mice inversely correlates with vessel pericyte coverage. Upon induction of experimental autoimmune encephalomyelitis (EAE), pericyte-deficient mice die of severe atypical EAE, which can be reversed with fingolimod, indicating that the mortality is due to the massive influx of immune cells into the brain. Additionally, administration of anti-VCAM-1 and anti-ICAM-1 antibodies reduces leukocyte infiltration and diminishes the severity of atypical EAE symptoms of Pdgfbret/ret mice, indicating that the proinflammatory endothelium due to absence of pericytes facilitates exaggerated neuroinflammation. Furthermore, we show that the presence of myelin peptide-specific peripheral T cells in Pdgfbret/ret ;2D2tg mice leads to the development of spontaneous neurological symptoms paralleled by the massive influx of leukocytes into the brain. These findings indicate that intrinsic changes within brain vasculature can promote the development of a neuroinflammatory disorder.
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Barrera Hematoencefálica/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Homeostasis/inmunología , Leucocitos/inmunología , Pericitos/inmunología , Animales , Barrera Hematoencefálica/patología , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/patología , Homeostasis/genética , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/inmunología , Leucocitos/patología , Ratones , Ratones Transgénicos , Pericitos/patología , Proteínas Proto-Oncogénicas c-sis/deficiencia , Proteínas Proto-Oncogénicas c-sis/inmunología , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/inmunologíaRESUMEN
We report quantitative label-free imaging with phase and polarization (QLIPP) for simultaneous measurement of density, anisotropy, and orientation of structures in unlabeled live cells and tissue slices. We combine QLIPP with deep neural networks to predict fluorescence images of diverse cell and tissue structures. QLIPP images reveal anatomical regions and axon tract orientation in prenatal human brain tissue sections that are not visible using brightfield imaging. We report a variant of U-Net architecture, multi-channel 2.5D U-Net, for computationally efficient prediction of fluorescence images in three dimensions and over large fields of view. Further, we develop data normalization methods for accurate prediction of myelin distribution over large brain regions. We show that experimental defects in labeling the human tissue can be rescued with quantitative label-free imaging and neural network model. We anticipate that the proposed method will enable new studies of architectural order at spatial scales ranging from organelles to tissue.
Microscopy is central to biological research and has enabled scientist to study the structure and dynamics of cells and their components within. Often, fluorescent dyes or trackers are used that can be detected under the microscope. However, this procedure can sometimes interfere with the biological processes being studied. Now, Guo, Yeh, Folkesson et al. have developed a new approach to examine structures within tissues and cells without the need for a fluorescent label. The technique, called QLIPP, uses the phase and polarization of the light passing through the sample to get information about its makeup. A computational model was used to decode the characteristics of the light and to provide information about the density and orientation of molecules in live cells and brain tissue samples of mice and human. This way, Guo et al. were able to reveal details that conventional microscopy would have missed. Then, a type of machine learning, known as 'deep learning', was used to translate the density and orientation images into fluorescence images, which enabled the researchers to predict specific structures in human brain tissue sections. QLIPP can be added as a module to a microscope and its software is available open source. Guo et al. hope that this approach can be used across many fields of biology, for example, to map the connectivity of nerve cells in the human brain or to identify how cells respond to infection. However, further work in automating other aspects, such as sample preparation and analysis, will be needed to realize the full benefits.
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Encéfalo/anatomía & histología , Aprendizaje Profundo , Feto/anatomía & histología , Imagenología Tridimensional/métodos , Animales , Anisotropía , Humanos , RatonesRESUMEN
Neuromyelitis optica spectrum disorder (NMOSD) is a CNS neuroinflammatory disorder, mediated by the pathogenic autoantibody aquaporin-4 (AQP4-IgG). Current treatment includes long-term use of immunomodulatory therapies, leading to increased rates of infections among this population. It is of interest therefore, to study how the COVID-19 pandemic affects NMOSD patients in terms of their disease activity. A 15-point questionnaire was administered to 33 participants living in Northern California with NMOSD, MS and other related disorders. Although none of the participants were diagnosed with COVID-19, our results show that 2 participants with NMOSD experienced new onset of neurological symptoms and 2 experienced worsening of previous neurological symptoms - suggesting a possible effect of pandemic-related stress on this CNS autoimmune disorder.
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Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/psicología , Neuromielitis Óptica/complicaciones , Neumonía Viral/epidemiología , Neumonía Viral/psicología , Distrés Psicológico , Brote de los Síntomas , Adulto , Betacoronavirus , COVID-19 , Femenino , Humanos , Masculino , Pandemias , Proyectos Piloto , SARS-CoV-2 , Encuestas y CuestionariosRESUMEN
We report a patient with relapsing-remitting multiple sclerosis, who developed rheumatoid arthritis after exposure to natalizumab. While some multiple sclerosis therapies are known to unmask autoimmune conditions, natalizumab is rarely implicated as a cause of alternative autoimmunity. This case illustrates an unusual clinical scenario which may support recent scientific work suggesting that, when natalizumab blocks T helper 1 cells from entering the central nervous system, T helper 17 cells may continue to migrate into immune-privileged spaces and cause pathologic inflammation. BRIEF BACKGROUND: Multiple sclerosis (MS) patients often suffer from concurrent autoimmune conditions, and may be at increased risk for developing rheumatoid arthritis (RA) (Langer-Gould et al., 2010; Tseng et al., 2016). While alemtuzumab and rituximab are known to unmask underlying autoimmune disorders, natalizumab is not commonly associated with autoimmunity. Here, we report a patient with relapsing-remitting MS who developed acute autoimmune arthropathy following exposure to natalizumab. CASE REPORT: A 45-year-old woman with autoimmune thyroiditis presented after episodes of left arm and right leg numbness. MRI showed multiple supratentorial and spinal cord demyelinating lesions. Lumbar puncture yielded CSF with a lymphocytic pleocytosis (11 leukocytes, 97% lymphocytes), normal protein, normal glucose, elevated immunoglobulin G index (2.24), and multiple unmatched oligoclonal bands. Her initial autoimmune workup revealed elevated anti-thyroid peroxidase antibody and rheumatoid factor (22 IU/mL, reference value < 14 IU/mL). The remainder of the patient's rheumatologic evaluation was normal, including aquaporin-4 antibody, anti-nuclear antibody, complements 3 and 4, and Sjogren's antibodies. She fulfilled 2017 McDonald Criteria for multiple sclerosis, and was started on dimethyl fumarate. Three months later, she developed left foot numbness and urinary incontinence. MRI spine showed a new lesion at C7, and her therapy was escalated to natalizumab. Immediately after her initial natalizumab infusion, she experienced transient neck and shoulder pain with decreased range of motion. She had no history of arthropathy. After her second natalizumab infusion, she developed persistent shoulder and hip pain. Her arthralgias resolved after a course of oral steroids. Two weeks after her second natalizumab infusion, she was seen by a rheumatologist who noted mild synovitis of both elbows and wrists on exam, but no significant inflammation involving her shoulders, fingers, knees, ankles, or feet. This time, she had significantly elevated anticyclic citrullinated peptide IgG (> 300 U/mL, reference value < 3 U/mL) and rheumatoid factor (71 IU/mL). Based on the number of small joints involved, and her positive serology, she met 2010 American College of Rheumatology Criteria for rheumatoid arthritis. Natalizumab was discontinued, and the patient was started on methotrexate, with which her rheumatoid arthritis has been controlled for the past two years.
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Artritis Reumatoide/etiología , Factores Inmunológicos/efectos adversos , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Natalizumab/efectos adversos , Femenino , Humanos , Persona de Mediana EdadRESUMEN
Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a newly recognized autoimmune central nervous system (CNS) inflammatory disorder, presenting with an array of neurological symptoms in association with autoantibodies against GFAP, a hallmark protein expressed on astrocytes. Limited knowledge is available on the disease pathogenesis and clinical outcome. Here, we report a case of autoimmune GFAP astrocytopathy presenting with encephalomyelitis and parkinsonism. Our patient was a 66-year old male who experienced progressive somnolence, apathy, anxiety, right arm tremor, urinary retention, progressive weakness, and falls over the course of three months, followed by acute delusional psychosis. His neurologic exam on hospital admission was notable for cognitive impairment, myoclonus, rigidity, right hand action tremor, bradykinesia, shuffling gait, and dysmetria. Cerebrospinal fluid examination showed elevated protein, lymphocytic pleocytosis, and one unique oligoclonal band. Magnetic resonance imaging (MRI) revealed non-specific T2/FLAIR hyperintensities in the brain and longitudinally extensive transverse myelitis in the cervical spine. FDG-PET showed a pattern of brain uptake suspicious for limbic encephalitis. Serum and CSF paraneoplastic panel showed presence of GFAP immunoglobulin G (IgG). Treatment with corticosteroids resulted in clinical and radiographic improvement. However, the patient was treated with anti-CD20 immunotherapy due to steroid-dependence. This case exemplifies the recently described neurologic syndrome of autoimmune GFAP astrocytopathy presenting with encephalomyelitis and parkinsonism, reversed by B lymphocyte depletion.
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Multiple sclerosis (MS) is the most common neurological immune-mediated disease leading to disability in young adults. The outcome of the disease is unpredictable, and over time, neurological disabilities accumulate. Interferon beta-1b was the first drug to be approved in the 1990s for relapsing-remitting MS to modulate the course of the disease. Over the past two decades, the treatment landscape has changed tremendously. Currently, more than a dozen drugs representing 1 substances with different mechanisms of action have been approved (interferon beta preparations, glatiramer acetate, fingolimod, siponimod, mitoxantrone, teriflunomide, dimethyl fumarate, cladribine, alemtuzumab, ocrelizumab, and natalizumab). Ocrelizumab was the first medication to be approved for primary progressive MS. The objective of this review is to present the modes of action of these drugs and their effects on the immunopathogenesis of MS. Each agent's clinical development and potential side effects are discussed.
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Inmunosupresores/inmunología , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/terapia , Animales , Humanos , Factores Inmunológicos/inmunologíaRESUMEN
Objective: To develop a resource of systematically collected, longitudinal clinical data and biospecimens for assisting in the investigation into neuromyelitis optica spectrum disorder (NMOSD) epidemiology, pathogenesis, and treatment. Methods: To illustrate its research-enabling purpose, epidemiologic patterns and disease phenotypes were assessed among enrolled subjects, including age at disease onset, annualized relapse rate (ARR), and time between the first and second attacks. Results: As of December 2017, the Collaborative International Research in Clinical and Longitudinal Experience Study (CIRCLES) had enrolled more than 1,000 participants, of whom 77.5% of the NMOSD cases and 71.7% of the controls continue in active follow-up. Consanguineous relatives of patients with NMOSD represented 43.6% of the control cohort. Of the 599 active cases with complete data, 84% were female, and 76% were anti-AQP4 seropositive. The majority were white/Caucasian (52.6%), whereas blacks/African Americans accounted for 23.5%, Hispanics/Latinos 12.4%, and Asians accounted for 9.0%. The median age at disease onset was 38.4 years, with a median ARR of 0.5. Seropositive cases were older at disease onset, more likely to be black/African American or Hispanic/Latino, and more likely to be female. Conclusions: Collectively, the CIRCLES experience to date demonstrates this study to be a useful and readily accessible resource to facilitate accelerating solutions for patients with NMOSD.
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Investigación Biomédica/tendencias , Internacionalidad , Colaboración Intersectorial , Neuromielitis Óptica/diagnóstico , Neuromielitis Óptica/etnología , Adulto , Investigación Biomédica/métodos , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neuromielitis Óptica/sangreRESUMEN
PURPOSE: To develop a 7T simultaneous multi-slice (SMS) 2D gradient-echo sequence for susceptibility contrast imaging, and to compare its quality to 3D imaging. METHODS: A frequency modulated and phase cycled RF pulse was designed to simultaneously excite multiple slices in multi-echo 2D gradient-echo imaging. The imaging parameters were chosen to generate images with susceptibility contrast, including T2*-weighted magnitude/phase images, susceptibility-weighted images and quantitative susceptibility/R2* maps. To compare their image quality with 3D gradient-echo imaging, both 2D and 3D imaging were performed on 11 healthy volunteers and 4 patients with multiple sclerosis (MS). The signal to noise ratio (SNR) in gray and white matter and their contrast to noise ratio (CNR) was simulated for the 2D and 3D magnitude images using parameters from the imaging. The experimental SNRs and CNRs were measured in gray/white matter and deep gray matter structures on magnitude, phase, R2* and QSM images from volunteers and the visibility of MS lesions on these images from patients was visually rated. All SNRs and CNRs were compared between the 2D and 3D imaging using a paired t-test. RESULTS: Although the 3D magnitude images still had significantly higher SNRs (by 13.0~17.6%), the 2D magnitude and QSM images generated significantly higher gray/white matter or globus pallidus/putamen contrast (by 13.3~87.5%) and significantly higher MS lesion contrast (by 5.9~17.3%). CONCLUSION: 2D SMS gradient-echo imaging can serve as an alternative to often used 3D imaging to obtain susceptibility-contrast-weighted images, with an advantage of providing better image contrast and MS lesion sensitivity.
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Sustancia Gris/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Adulto , Algoritmos , Mapeo Encefálico/métodos , Medios de Contraste/farmacología , Femenino , Globo Pálido/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Putamen/diagnóstico por imagen , Relación Señal-Ruido , Programas InformáticosRESUMEN
The critical role of sphingosine-1-phosphate (S1P) signaling in lymphocyte trafficking is well recognized, however, the contribution of myeloid cell-S1P signaling in neuroimmunity is less well understood. We previously reported that C57BL/6J mice harboring phosphorylation defective S1P receptor 1 (S1P1) (with mutated serines in the carboxyl terminus, leading to impaired receptor internalization) [S1P1(S5A)] developed severe, TH17-dominant experimental autoimmune encephalomyelitis. In this study, we demonstrate that S1P1-mediated TH17 polarization is not an intrinsic T cell effect, but dependent on sustained S1P1 signaling in myeloid cells. First, utilizing the S1P1(S5A) mice in the EAE model, we observed that S1P1 activated and enhanced antigen presentation function in myeloid cells. Second, sequential phosphorylation of STAT3 occurred in dendritic cells, monocytes, and macrophages/microglia during neuroinflammation. Third, we show that pro-inflammatory (CD45hiCD11b+Ly6Chi) monocytes contribute to TH17 differentiation and neuroinflammation by regulating IL-6 expression. Finally, results from experiments utilizing myeloid cell-specific S1P1 overexpression (S1pr1f/stop/f:LysMCre) mice demonstrate that myeloid cell S1P1 directly contributes to severity of neuroinflammation. These findings reveal the critical contribution of myeloid-S1P1 signaling in CNS autoimmunity.
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Autoinmunidad/inmunología , Sistema Nervioso Central/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Inflamación/inmunología , Células Mieloides/inmunología , Receptores de Esfingosina-1-Fosfato/inmunología , Animales , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/patología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Monocitos/inmunología , Monocitos/metabolismo , Células Mieloides/metabolismo , Factor de Transcripción STAT3/inmunología , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/inmunología , Receptores de Esfingosina-1-Fosfato/genética , Receptores de Esfingosina-1-Fosfato/metabolismo , Células Th17/inmunología , Células Th17/metabolismoRESUMEN
BACKGROUND: Fingolimod is a sphingosine 1-phosphate receptor modulator for the treatment of patients with relapsing forms of multiple sclerosis (RMS). Fingolimod sequesters lymphocytes within lymphoid tissue thereby reducing the counts of circulating lymphocytes. However, fingolimod's effects on the innate and adaptive components of the immune system are incompletely understood. OBJECTIVE: The FLUENT study will investigate temporal changes in circulating immune cell subsets in patients with RMS treated with fingolimod. Secondary objectives include examining the association between anti-John Cunningham virus (JCV) antibody status/index and phenotypic changes in innate and T and B cell subsets in patients on fingolimod therapy, and the association between serum neurofilament levels and clinical outcomes. METHODS: FLUENT is a prospective, multicenter, two-cohort, nonrandomized, open-label Phase IV study. Cohort 1 will include fingolimod-naïve patients and Cohort 2 will include patients who have received fingolimod 0.5 mg/day continuously for ≥2 years. Changes in the cellular components of the innate and adaptive immune system will be characterized over 12 months. RESULTS: The study is ongoing. CONCLUSION: FLUENT may provide evidence for the use of immunologic profiling in predicting efficacy and risk of infection in patients with RMS treated with fingolimod.
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OBJECTIVE: We sought to confirm the presence and frequency of B cells and Epstein-Barr virus (EBV) (latent and lytic phase) antigens in archived MS and non-MS brain tissue by immunohistochemistry. METHODS: We quantified the type and location of B-cell subsets within active and chronic MS brain lesions in relation to viral antigen expression. The presence of EBV-infected cells was further confirmed by in situ hybridization to detect the EBV RNA transcript, EBV-encoded RNA-1 (EBER-1). RESULTS: We report the presence of EBV latent membrane protein 1 (LMP-1) in 93% of MS and 78% of control brains, with a greater percentage of MS brains containing CD138+ plasma cells and LMP-1-rich populations. Notably, 78% of chronic MS lesions and 33.3% of non-MS brains contained parenchymal CD138+ plasma cells. EBV early lytic protein, EBV immediate-early lytic gene (BZLF1), was also observed in 46% of MS, primarily in association with chronic lesions and 44% of non-MS brain tissue. Furthermore, 85% of MS brains revealed frequent EBER-positive cells, whereas non-MS brains seldom contained EBER-positive cells. EBV infection was detectable, by immunohistochemistry and by in situ hybridization, in both MS and non-MS brains, although latent virus was more prevalent in MS brains, while lytic virus was restricted to chronic MS lesions. CONCLUSIONS: Together, our observations suggest an uncharacterized link between the EBV virus life cycle and MS pathogenesis.
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Blood-brain barrier (BBB) disruption alters the composition of the brain microenvironment by allowing blood proteins into the CNS. However, whether blood-derived molecules serve as extrinsic inhibitors of remyelination is unknown. Here we show that the coagulation factor fibrinogen activates the bone morphogenetic protein (BMP) signaling pathway in oligodendrocyte progenitor cells (OPCs) and suppresses remyelination. Fibrinogen induces phosphorylation of Smad 1/5/8 and inhibits OPC differentiation into myelinating oligodendrocytes (OLs) while promoting an astrocytic fate in vitro. Fibrinogen effects are rescued by BMP type I receptor inhibition using dorsomorphin homolog 1 (DMH1) or CRISPR/Cas9 activin A receptor type I (ACVR1) knockout in OPCs. Fibrinogen and the BMP target Id2 are increased in demyelinated multiple sclerosis (MS) lesions. Therapeutic depletion of fibrinogen decreases BMP signaling and enhances remyelination in vivo. Targeting fibrinogen may be an upstream therapeutic strategy to promote the regenerative potential of CNS progenitors in diseases with remyelination failure.
Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Fibrinógeno/farmacología , Células Precursoras de Oligodendrocitos/metabolismo , Remielinización/efectos de los fármacos , Receptores de Activinas Tipo I/efectos de los fármacos , Receptores de Activinas Tipo I/genética , Receptores de Activinas Tipo I/metabolismo , Animales , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/patología , Fibrinógeno/antagonistas & inhibidores , Lisofosfatidilcolinas/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis por Micromatrices , Vaina de Mielina/metabolismo , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Plásmidos/genética , Transducción de Señal/efectos de los fármacosRESUMEN
The small heat shock protein αB-crystallin (CRYAB) has been implicated in multiple sclerosis (MS) pathogenesis. Earlier studies have indicated that CRYAB inhibits inflammation and attenuates clinical disease when administered in the experimental autoimmune encephalomyelitis model of MS. In this study, we evaluated the role of CRYAB in primary demyelinating events. Using the cuprizone model of demyelination, a noninflammatory model that allows the analysis of glial responses in MS, we show that endogenous CRYAB expression is associated with increased severity of demyelination. Moreover, we demonstrate a strong correlation between the expression of CRYAB and the extent of reactive astrogliosis in demyelinating areas and in in vitro assays. In addition, we reveal that CRYAB is differentially phosphorylated in astrocytes in active demyelinating MS lesions, as well as in cuprizone-induced lesions, and that this phosphorylation is required for the reactive astrocyte response associated with demyelination. Furthermore, taking a proteomics approach to identify proteins that are bound by the phosphorylated forms of CRYAB in primary cultured astrocytes, we show that there is clear differential binding of protein targets due to the specific phosphorylation of CRYAB. Subsequent Ingenuity Pathway Analysis of these targets reveals implications for intracellular pathways and biological processes that could be affected by these modifications. Together, these findings demonstrate that astrocytes play a pivotal role in demyelination, making them a potential target for therapeutic intervention, and that phosphorylation of CRYAB is a key factor supporting the pathogenic response of astrocytes to oligodendrocyte injury.