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1.
J Neuroinflammation ; 15(1): 174, 2018 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-29866203

RESUMEN

BACKGROUND: Subtle adjustment of the activation status of CNS resident microglia and peripheral macrophages, to promote their neuroprotective and neuroregenerative functions, may facilitate research towards curing neurodegenerative disorders. In the present study, we investigated whether targeted intracerebral delivery of the anti-inflammatory cytokine interleukin (IL)13, by means of transplanting IL13-expressing mesenchymal stem cells (IL13-MSCs), can promote a phenotypic switch in both microglia and macrophages during the pro-inflammatory phase in a mouse model of ischemic stroke. METHODS: We used the CX3CR1eGFP/+ CCR2RFP/+ transgenic mouse model to separately recognize brain-resident microglia from infiltrated macrophages. Quantitative immunohistochemical analyses were applied to characterize polarization phenotypes of both cell types. RESULTS: Distinct behaviors of both cell populations were noted dependent on the anatomical site of the lesion. Immunohistochemistry revealed that mice grafted with IL13-MSCs, in contrast to non-grafted and MSC-grafted control mice, were able to drive recruited microglia and macrophages into an alternative activation state, as visualized by a significant increase of Arg-1 and a noticeable decrease of MHC-II expression at day 14 after ischemic stroke. Interestingly, both Arg-1 and MHC-II were expressed more abundantly in macrophages than in microglia, further confirming the distinct behavior of both cell populations. CONCLUSIONS: The current data highlight the importance of controlled and localized delivery of the anti-inflammatory cytokine IL13 for modulation of both microglia and macrophage responses after ischemic stroke, thereby providing pre-clinical rationale for the application of L13-MSCs in future investigations of neurodegenerative disorders.


Asunto(s)
Antiinflamatorios/uso terapéutico , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/terapia , Interleucina-13/uso terapéutico , Macrófagos/efectos de los fármacos , Microglía/efectos de los fármacos , Animales , Receptor 1 de Quimiocinas CX3C/genética , Receptor 1 de Quimiocinas CX3C/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/fisiología , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/fisiopatología , Interleucina-13/genética , Interleucina-13/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Macrófagos/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microglía/metabolismo , Movimiento/fisiología , Fuerza Muscular , Propiocepción , ARN Mensajero/metabolismo , Receptores CCR2/genética , Receptores CCR2/metabolismo , Tacto/fisiología , Transducción Genética
2.
Glia ; 64(12): 2181-2200, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27685637

RESUMEN

Detrimental inflammatory responses in the central nervous system are a hallmark of various brain injuries and diseases. With this study we provide evidence that lentiviral vector-mediated expression of the immune-modulating cytokine interleukin 13 (IL-13) induces an alternative activation program in both microglia and macrophages conferring protection against severe oligodendrocyte loss and demyelination in the cuprizone mouse model for multiple sclerosis (MS). First, IL-13 mediated modulation of cuprizone induced lesions was monitored using T2 -weighted magnetic resonance imaging and magnetization transfer imaging, and further correlated with quantitative histological analyses for inflammatory cell influx, oligodendrocyte death, and demyelination. Second, following IL-13 immune gene therapy in cuprizone-treated eGFP+ bone marrow chimeric mice, we provide evidence that IL-13 directs the polarization of both brain-resident microglia and infiltrating macrophages towards an alternatively activated phenotype, thereby promoting the conversion of a pro-inflammatory environment toward an anti-inflammatory environment, as further evidenced by gene expression analyses. Finally, we show that IL-13 immune gene therapy is also able to limit lesion severity in a pre-existing inflammatory environment. In conclusion, these results highlight the potential of IL-13 to modulate microglia/macrophage responses and to improve disease outcome in a mouse model for MS. GLIA 2016;64:2181-2200.


Asunto(s)
Enfermedades Desmielinizantes/terapia , Encefalitis/terapia , Terapia Genética/métodos , Interleucina-13 , Macrófagos/efectos de los fármacos , Microglía/efectos de los fármacos , Animales , Antígenos de Diferenciación/metabolismo , Trasplante de Médula Ósea , Cuprizona/toxicidad , Citocinas/genética , Citocinas/metabolismo , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/diagnóstico por imagen , Modelos Animales de Enfermedad , Encefalitis/inducido químicamente , Encefalitis/diagnóstico por imagen , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Interleucina-13/genética , Interleucina-13/metabolismo , Interleucina-13/uso terapéutico , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Inhibidores de la Monoaminooxidasa/toxicidad , Proteínas de la Mielina/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Transducción Genética
3.
J Neuroinflammation ; 13(1): 288, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27829467

RESUMEN

BACKGROUND: Promoting the neuroprotective and repair-inducing effector functions of microglia and macrophages, by means of M2 polarisation or alternative activation, is expected to become a new therapeutic approach for central nervous system (CNS) disorders in which detrimental pro-inflammatory microglia and/or macrophages display a major contribution to the neuropathology. In this study, we present a novel in vivo approach using intracerebral grafting of mesenchymal stem cells (MSC) genetically engineered to secrete interleukin 13 (IL13-MSC). METHODS: In the first experimental setup, control MSC and IL13-MSC were grafted in the CNS of eGFP+ bone marrow chimaeric C57BL/6 mice to histologically evaluate IL13-mediated expression of several markers associated with alternative activation, including arginase1 and Ym1, on MSC graft-recognising microglia and MSC graft-infiltrating macrophages. In the second experimental setup, IL13-MSC were grafted on the right side (or on both the right and left sides) of the splenium of the corpus callosum in wild-type C57BL/6 mice and in C57BL/6 CX3CR1eGFP/+CCR2RFP/+ transgenic mice. Next, CNS inflammation and demyelination was induced by means of a cuprizone-supplemented diet. The influence of IL13-MSC grafting on neuropathological alterations was monitored by non-invasive T 2-weighted magnetic resonance imaging (MRI) and quantitative histological analyses, as compared to cuprizone-treated mice with control MSC grafts and/or cuprizone-treated mice without MSC injection. RESULTS: In the first part of this study, we demonstrate that MSC graft-associated microglia and MSC graft-infiltrating macrophages are forced into alternative activation upon grafting of IL13-MSC, but not upon grafting of control MSC. In the second part of this study, we demonstrate that grafting of IL13-MSC, in addition to the recruitment of M2 polarised macrophages, limits cuprizone-induced microgliosis, oligodendrocyte death and demyelination. Furthermore, we here demonstrate that injection of IL13-MSC at both sides of the splenium leads to a superior protective effect as compared to a single injection at one side of the splenium. CONCLUSIONS: Controlled and localised production of IL13 by means of intracerebral MSC grafting has the potential to modulate cell graft- and pathology-associated microglial/macrophage responses, and to interfere with oligodendrocyte death and demyelinating events in the cuprizone mouse model.


Asunto(s)
Cuprizona/toxicidad , Enfermedades Desmielinizantes , Gliosis/etiología , Interleucina-13/metabolismo , Trasplante de Células Madre Mesenquimatosas , Inhibidores de la Monoaminooxidasa/toxicidad , Oligodendroglía/patología , Animales , Línea Celular Transformada , Citocinas/genética , Citocinas/metabolismo , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/diagnóstico por imagen , Enfermedades Desmielinizantes/patología , Enfermedades Desmielinizantes/cirugía , Modelos Animales de Enfermedad , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Imagen por Resonancia Magnética , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteína Básica de Mielina/metabolismo , Oligodendroglía/efectos de los fármacos
4.
Alzheimers Dement ; 12(9): 964-976, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27107518

RESUMEN

INTRODUCTION: In Alzheimer's disease (AD), pathologic amyloid-beta (Aß) is synaptotoxic and impairs neuronal function at the microscale, influencing brain networks at the macroscale before Aß deposition. The latter can be detected noninvasively, in vivo, using resting-state functional MRI (rsfMRI), a technique used to assess brain functional connectivity (FC). METHODS: RsfMRI was performed longitudinally in TG2576 and PDAPP mice, starting before Aß deposition to determine the earliest FC changes. Additionally, the role of pathologic Aß on early FC alterations was investigated by treating TG2576 mice with the 3D6 anti-Aß-antibody. RESULTS: Both transgenic models showed hypersynchronized FC before Aß deposition and hyposynchronized FC at later stages. Early anti-Aß treatment in TG2576 mice prevented hypersynchronous FC and the associated synaptic impairments and excitatory/inhibitory disbalances. DISCUSSION: Hypersynchrony of FC may be used as a new noninvasive read out of early AD and can be recovered by anti-Aß treatment, encouraging preventive treatment strategies in familial AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Enfermedad de Alzheimer/diagnóstico por imagen , Animales , Autoanticuerpos/farmacología , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Circulación Cerebrovascular/fisiología , Sincronización Cortical/fisiología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Estudios Longitudinales , Imagen por Resonancia Magnética , Ratones Transgénicos , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Fármacos Neuroprotectores/farmacología , Oxígeno/sangre , Placa Amiloide/diagnóstico por imagen , Placa Amiloide/fisiopatología , Placa Amiloide/prevención & control , Síntomas Prodrómicos , Descanso
5.
Neuroimage ; 114: 128-35, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25871629

RESUMEN

Non-invasive measures of well-known pathological hallmarks of multiple sclerosis (MS) such as demyelination, inflammation and axonal injury would serve as useful markers to monitor disease progression and evaluate potential therapies. To this end, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) provides a powerful means to monitor metabolic changes in the brain and may be sensitive to these pathological hallmarks. In our study, we used the cuprizone mouse model to study pathological features of MS, such as inflammation, de- and remyelination, in a highly reproducible manner. C57BL/6J mice were challenged with a 0.2% cuprizone diet for 6-weeks to induce demyelination, thereafter the mice were put on a cuprizone free diet for another 6weeks to induce spontaneous remyelination. We employed in vivo (1)H-MRS to longitudinally monitor metabolic changes in the corpus callosum of cuprizone-fed mice during the demyelination (weeks 4 and 6) and spontaneous remyelination (week 12) phases. The MRS spectra were quantified with LCModel and since the total creatine (tCr) levels did not change over time or between groups, metabolite concentrations were expressed as ratios relative to tCr. After 4 and 6weeks of cuprizone treatment a significant increase in taurine/tCr and a significant reduction in total N-acetylaspartate/tCr, total choline-containing compounds/tCr and glutamate/tCr could be observed compared to mice under normal diet. At week 12, when almost full remyelination was established, no statistically significant metabolic differences were present between the control and cuprizone group. Our results suggest that these metabolic changes may represent sensitive markers for cuprizone induced demyelination, axonal injury and inflammation. To the best of our knowledge, this is the first longitudinal in vivo (1)H-MRS study that monitored biochemical changes in the corpus callosum of cuprizone fed mice.


Asunto(s)
Cuerpo Calloso/metabolismo , Esclerosis Múltiple/metabolismo , Vaina de Mielina/metabolismo , Espectroscopía de Protones por Resonancia Magnética , Animales , Cuerpo Calloso/patología , Cuprizona , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos C57BL , Esclerosis Múltiple/inducido químicamente , Esclerosis Múltiple/patología , Vaina de Mielina/patología
6.
NMR Biomed ; 28(4): 505-13, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25802215

RESUMEN

Conventional MRI is frequently used during the diagnosis of multiple sclerosis but provides only little additional pathological information. Proton MRS ((1) H-MRS), however, provides biochemical information on the lesion pathology by visualization of a spectrum of metabolites. In this study we aimed to better understand the changes in metabolite concentrations following demyelination of the white matter. Therefore, we used the cuprizone model, a well-established mouse model to mimic type III human multiple sclerosis demyelinating lesions. First, we identified CX3 CL1/CX3 CR1 signaling as a major regulator of microglial activity in the cuprizone mouse model. Compared with control groups (heterozygous CX3 CR1(+/-) C57BL/6 mice and wild type CX3 CR1(+/+) C57BL/6 mice), microgliosis, astrogliosis, oligodendrocyte cell death and demyelination were shown to be highly reduced or absent in CX3 CR1(-/-) C57BL/6 mice. Second, we show that (1) H-MRS metabolite spectra are different when comparing cuprizone-treated CX3 CR1(-/-) mice showing mild demyelination with cuprizone-treated CX3 CR1(+/+) mice showing severe demyelination and demyelination-associated inflammation. Following cuprizone treatment, CX3 CR1(+/+) mice show a decrease in the Glu, tCho and tNAA concentrations as well as an increased Tau concentration. In contrast, following cuprizone treatment CX3 CR1(-/-) mice only showed a decrease in tCho and tNAA concentrations. Therefore, (1) H-MRS might possibly allow us to discriminate demyelination from demyelination-associated inflammation via changes in Tau and Glu concentration. In addition, the observed decrease in tCho concentration in cuprizone-induced demyelinating lesions should be further explored as a possible diagnostic tool for the early identification of human MS type III lesions.


Asunto(s)
Enfermedades Desmielinizantes/patología , Gliosis/patología , Imagen por Resonancia Magnética , Neuroimagen/métodos , Espectroscopía de Protones por Resonancia Magnética , Animales , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Química Encefálica , Colina/análisis , Creatina/análisis , Cuprizona/toxicidad , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/diagnóstico , Dipéptidos/análisis , Modelos Animales de Enfermedad , Femenino , Gliosis/inducido químicamente , Gliosis/diagnóstico , Masculino , Ratones , Ratones Endogámicos C57BL , Oligodendroglía/patología , Fosfocreatina/análisis
7.
Neuroimage ; 86: 99-110, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23933305

RESUMEN

Multiple sclerosis is a devastating demyelinating disease of the central nervous system (CNS) in which endogenous remyelination, and thus recovery, often fails. Although the cuprizone mouse model allowed elucidation of many molecular factors governing remyelination, currently very little is known about the spatial origin of the oligodendrocyte progenitor cells that initiate remyelination in this model. Therefore, we here investigated in this model whether subventricular zone (SVZ) neural stem/progenitor cells (NSPCs) contribute to remyelination of the splenium following cuprizone-induced demyelination. Experimentally, from the day of in situ NSPC labeling, C57BL/6J mice were fed a 0.2% cuprizone diet during a 4-week period and then left to recover on a normal diet for 8weeks. Two in situ labeling strategies were employed: (i) NSPCs were labeled by intraventricular injection of micron-sized iron oxide particles and then followed up longitudinally by means of magnetic resonance imaging (MRI), and (ii) SVZ NSPCs were transduced with a lentiviral vector encoding the eGFP and Luciferase reporter proteins for longitudinal monitoring by means of in vivo bioluminescence imaging (BLI). In contrast to preceding suggestions, no migration of SVZ NSPC towards the demyelinated splenium was observed using both MRI and BLI, and further validated by histological analysis, thereby demonstrating that SVZ NSPCs are unable to contribute directly to remyelination of the splenium in the cuprizone model. Interestingly, using longitudinal BLI analysis and confirmed by histological analysis, an increased migration of SVZ NSPC-derived neuroblasts towards the olfactory bulb was observed following cuprizone treatment, indicative for a potential link between CNS inflammation and increased neurogenesis.


Asunto(s)
Ventrículos Cerebrales/patología , Cuerpo Calloso/patología , Enfermedades Desmielinizantes/patología , Imagen de Difusión por Resonancia Magnética/métodos , Fibras Nerviosas Mielínicas/patología , Células-Madre Neurales/patología , Bulbo Olfatorio/patología , Animales , Movimiento Celular , Rastreo Celular/métodos , Cuprizona , Enfermedades Desmielinizantes/inducido químicamente , Femenino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente/métodos , Imagen Multimodal/métodos , Vías Nerviosas/patología , Neurogénesis
8.
Front Immunol ; 15: 1446748, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224590

RESUMEN

Multiple sclerosis (MS) is a devastating immune-mediated disorder of the central nervous system resulting in progressive disability accumulation. As there is no cure available yet for MS, the primary therapeutic objective is to reduce relapses and to slow down disability progression as early as possible during the disease to maintain and/or improve health-related quality of life. However, optimizing treatment for people with MS (pwMS) is complex and challenging due to the many factors involved and in particular, the high degree of clinical and sub-clinical heterogeneity in disease progression among pwMS. In this paper, we discuss these many different challenges complicating treatment optimization for pwMS as well as how a shift towards a more pro-active, data-driven and personalized medicine approach could potentially improve patient outcomes for pwMS. We describe how the 'Clinical Impact through AI-assisted MS Care' (CLAIMS) project serves as a recent example of how to realize such a shift towards personalized treatment optimization for pwMS through the development of a platform that offers a holistic view of all relevant patient data and biomarkers, and then using this data to enable AI-supported prognostic modelling.


Asunto(s)
Inteligencia Artificial , Esclerosis Múltiple , Medicina de Precisión , Humanos , Esclerosis Múltiple/terapia , Esclerosis Múltiple/inmunología , Medicina de Precisión/métodos , Progresión de la Enfermedad , Biomarcadores , Calidad de Vida , Pronóstico
9.
Diagnostics (Basel) ; 12(7)2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35885513

RESUMEN

Early diagnosis of COVID-19 is required to provide the best treatment to our patients, to prevent the epidemic from spreading in the community, and to reduce costs associated with the aggravation of the disease. We developed a decision tree model to evaluate the impact of using an artificial intelligence-based chest computed tomography (CT) analysis software (icolung, icometrix) to analyze CT scans for the detection and prognosis of COVID-19 cases. The model compared routine practice where patients receiving a chest CT scan were not screened for COVID-19, with a scenario where icolung was introduced to enable COVID-19 diagnosis. The primary outcome was to evaluate the impact of icolung on the transmission of COVID-19 infection, and the secondary outcome was the in-hospital length of stay. Using EUR 20000 as a willingness-to-pay threshold, icolung is cost-effective in reducing the risk of transmission, with a low prevalence of COVID-19 infections. Concerning the hospitalization cost, icolung is cost-effective at a higher value of COVID-19 prevalence and risk of hospitalization. This model provides a framework for the evaluation of AI-based tools for the early detection of COVID-19 cases. It allows for making decisions regarding their implementation in routine practice, considering both costs and effects.

10.
Immunol Cell Biol ; 89(4): 511-6, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21102538

RESUMEN

Currently, much attention is given to the development of cellular therapies for treatment of central nervous system (CNS) injuries. Diverse cell implantation strategies, either to directly replace damaged neural tissue or to create a neuroregenerative environment, are proposed to restore impaired brain function. However, because of the complexity of the CNS, it is now becoming clear that the contribution of cell implantation into the brain will mainly act in a supportive manner. In addition, given the time dependence of neural development during embryonic and post-natal life, cellular implants, either self or non-self, will most likely have to interact for a sustained period of time with both healthy and injured neural tissue. The latter also implies potential recognition of cellular implants by the innate immune system of the brain. In this review, we will emphasize on preclinical observations in rodents, regarding the recognition and immunogenicity of autologous, allogeneic and xenogeneic cellular implants in the CNS of immune-competent hosts. Taken together, we here suggest that a profound study of the interaction between cellular grafts and the brain's innate immune system will be inevitable before clinical cell transplantation in the CNS can be performed successfully.


Asunto(s)
Encéfalo/inmunología , Trasplante de Células , Inmunidad Innata/inmunología , Inmunología del Trasplante/inmunología , Animales , Tratamiento Basado en Trasplante de Células y Tejidos , Enfermedades del Sistema Nervioso Central/terapia , Humanos
11.
Alzheimers Res Ther ; 10(1): 1, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29370870

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia in the elderly population. In this study, we used the APP/PS1 transgenic mouse model to explore the feasibility of using diffusion kurtosis imaging (DKI) as a tool for the early detection of microstructural changes in the brain due to amyloid-ß (Aß) plaque deposition. METHODS: We longitudinally acquired DKI data of wild-type (WT) and APP/PS1 mice at 2, 4, 6 and 8 months of age, after which these mice were sacrificed for histological examination. Three additional cohorts of mice were also included at 2, 4 and 6 months of age to allow voxel-based co-registration between diffusion tensor and diffusion kurtosis  metrics and immunohistochemistry. RESULTS: Changes were observed in diffusion tensor (DT) and diffusion kurtosis (DK) metrics in many of the 23 regions of interest that were analysed. Mean and axial kurtosis were greatly increased owing to Aß-induced pathological changes in the motor cortex of APP/PS1 mice at 4, 6 and 8 months of age. Additionally, fractional anisotropy (FA) was decreased in APP/PS1 mice at these respective ages. Linear discriminant analysis of the motor cortex data indicated that combining diffusion tensor and diffusion kurtosis metrics permits improved separation of WT from APP/PS1 mice compared with either diffusion tensor or diffusion kurtosis metrics alone. We observed that mean kurtosis and FA are the critical metrics for a correct genotype classification. Furthermore, using a newly developed platform to co-register the in vivo diffusion-weighted magnetic resonance imaging with multiple 3D histological stacks, we found high correlations between DK metrics and anti-Aß (clone 4G8) antibody, glial fibrillary acidic protein, ionised calcium-binding adapter molecule 1 and myelin basic protein immunohistochemistry. Finally, we observed reduced FA in the septal nuclei of APP/PS1 mice at all ages investigated. The latter was at least partially also observed by voxel-based statistical parametric mapping, which showed significantly reduced FA in the septal nuclei, as well as in the corpus callosum, of 8-month-old APP/PS1 mice compared with WT mice. CONCLUSIONS: Our results indicate that DKI metrics hold tremendous potential for the early detection and longitudinal follow-up of Aß-induced pathology.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador , Placa Amiloide/diagnóstico por imagen , Envejecimiento/patología , Animales , Encéfalo/patología , Modelos Animales de Enfermedad , Diagnóstico Precoz , Estudios de Factibilidad , Estudios de Seguimiento , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional , Inmunohistoquímica , Estudios Longitudinales , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Placa Amiloide/patología
12.
Cell Transplant ; 24(8): 1481-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25197881

RESUMEN

While multiple rodent preclinical studies, and to a lesser extent human clinical trials, claim the feasibility, safety, and potential clinical benefit of cell grafting in the central nervous system (CNS), currently only little convincing knowledge exists regarding the actual fate of the grafted cells and their effect on the surrounding environment (or vice versa). Our preceding studies already indicated that only a minor fraction of the initially grafted cell population survives the grafting process, while the surviving cell population becomes invaded by highly activated microglia/macrophages and surrounded by reactive astrogliosis. In the current study, we further elaborate on early cellular and inflammatory events following syngeneic grafting of eGFP(+) mouse embryonic fibroblasts (mEFs) in the CNS of immunocompetent mice. Based on obtained quantitative histological data, we here propose a detailed mathematically derived working model that sequentially comprises hypoxia-induced apoptosis of grafted mEFs, neutrophil invasion, neoangiogenesis, microglia/macrophage recruitment, astrogliosis, and eventually survival of a limited number of grafted mEFs. Simultaneously, we observed that the cellular events following mEF grafting activates the subventricular zone neural stem and progenitor cell compartment. This proposed model therefore further contributes to our understanding of cell graft-induced cellular responses and will eventually allow for successful manipulation of this intervention.


Asunto(s)
Sistema Nervioso Central/metabolismo , Inflamación , Ventrículos Laterales/citología , Neutrófilos/inmunología , Animales , Apoptosis , Proliferación Celular , Células Cultivadas , Sistema Nervioso Central/inmunología , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Fibroblastos/trasplante , Genes Reporteros , Supervivencia de Injerto , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Hipoxia , Macrófagos/citología , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microglía/metabolismo , Modelos Biológicos , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neutrófilos/citología
13.
Cell Transplant ; 24(2): 223-33, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24380384

RESUMEN

Although intracerebral transplantation of various fibroblast(-like) cell populations has been shown feasible, little is known about the actual in vivo remodeling of these cellular grafts and their environment. In this study, we aimed to compare the in vitro and in vivo behavior of two phenotypically similar-but developmentally distinct-fibroblast-like cell populations, namely, mouse embryonic fibroblasts (mEFs) and mouse fetal membrane-derived stromal cells (mFMSCs). While both mEFs and mFMSCs are readily able to reduce TNF-α secretion by LPS/IFN-γ-activated BV-2 microglia, mFMSCs and mEFs display strikingly opposite behavior with regard to VEGF production under normal and inflammatory conditions. Whereas mFMSCs downregulate VEGF production upon coculture with LPS/IFN-γ-activated BV-2 microglia, mEFs upregulate VEGF production in the presence of LPS/IFN-γ-activated BV-2 microglia. Subsequently, in vivo grafting of mFMSCs and mEFs revealed no difference in microglial and astroglial responses toward the cellular grafts. However, mFMSC grafts displayed a lower degree of neoangiogenesis compared to mEF grafts, thereby potentially explaining the lower cell number able to survive in mFMSC grafts. In summary, our results suggest that physiological differences between fibroblast-like cell populations might lie at the basis of variations in histopathological and/or clinical outcome following cell grafting in mouse brain.


Asunto(s)
Encéfalo/patología , Embrión de Mamíferos/citología , Membranas Extraembrionarias/citología , Fibroblastos/trasplante , Células del Estroma/trasplante , Animales , Diferenciación Celular , Células Cultivadas , Técnicas de Cocultivo , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Inmunofenotipificación , Interferón gamma/farmacología , Lipopolisacáridos/toxicidad , Ratones , Ratones Endogámicos C57BL , Microglía/citología , Microglía/efectos de los fármacos , Microglía/metabolismo , Células del Estroma/citología , Células del Estroma/metabolismo , Trasplante Homólogo , Factor de Necrosis Tumoral alfa/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
14.
Neurosci Biobehav Rev ; 47: 485-505, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25445182

RESUMEN

The cuprizone mouse model allows the investigation of the complex molecular mechanisms behind nonautoimmune-mediated demyelination and spontaneous remyelination. While it is generally accepted that oligodendrocytes are specifically vulnerable to cuprizone intoxication due to their high metabolic demands, a comprehensive overview of the etiology of cuprizone-induced pathology is still missing to date. In this review we extensively describe the physico-chemical mode of action of cuprizone and discuss the molecular and enzymatic mechanisms by which cuprizone induces metabolic stress, oligodendrocyte apoptosis, myelin degeneration and eventually axonal and neuronal pathology. In addition, we describe the dual effector function of the immune system which tightly controls demyelination by effective induction of oligodendrocyte apoptosis, but in contrast also paves the way for fast and efficient remyelination by the secretion of neurotrophic factors and the clearance of cellular and myelinic debris. Finally, we discuss the many clinical symptoms that can be observed following cuprizone treatment, and how these strengthened the cuprizone model as a useful tool to study human multiple sclerosis, schizophrenia and epilepsy.


Asunto(s)
Encéfalo/patología , Cuprizona , Modelos Animales de Enfermedad , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Neuroglía/patología , Neuronas/patología , Animales , Encéfalo/metabolismo , Ratones , Esclerosis Múltiple/inducido químicamente , Esclerosis Múltiple/metabolismo , Vaina de Mielina/metabolismo , Neuroglía/metabolismo , Neuronas/metabolismo , Estrés Oxidativo/fisiología
15.
Methods Mol Biol ; 1213: 265-83, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25173390

RESUMEN

Preclinical animal studies involving intracerebral (stem) cell grafting are gaining popularity in many laboratories due to the reported beneficial effects of cell grafting on various diseases or traumata of the central nervous system (CNS). In this chapter, we describe a histological workflow to characterize and quantify cellular events following neural and fibroblast(-like) stem cell grafting in healthy and demyelinated CNS tissue. First, we provide standardized protocols to isolate and culture eGFP(+) neural and fibroblast(-like) stem cells from embryonic mouse tissue. Second, we describe flow cytometric procedures to determine cell viability, eGFP transgene expression, and the expression of different stem cell lineage markers. Third, we explain how to induce reproducible demyelination in the CNS of mice by means of cuprizone administration, a validated mouse model for human multiple sclerosis. Fourth, the technical procedures for cell grafting in the CNS are explained in detail. Finally, an optimized and validated workflow for the quantitative histological analysis of cell graft survival and endogenous astroglial and microglial responses is provided.


Asunto(s)
Enfermedades Desmielinizantes/terapia , Células-Madre Neurales/citología , Trasplante de Células Madre , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Modelos Animales de Enfermedad , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Citometría de Flujo , Expresión Génica , Genes Reporteros , Supervivencia de Injerto , Inmunohistoquímica , Ratones , Células-Madre Neurales/metabolismo , Medicina Regenerativa , Transgenes
16.
Stem Cell Res Ther ; 4(4): 101, 2013 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-23998480

RESUMEN

Over the past decade a lot of research has been performed towards the therapeutic use of mesenchymal stem cells (MSCs) in neurodegenerative and neuroinflammatory diseases. MSCs have shown to be beneficial in different preclinical studies of central nervous system (CNS) disorders due to their immunomodulatory properties and their capacity to secrete various growth factors. Nevertheless, most of the transplanted cells die within the first hours after transplantation and induce a neuroinflammatory response. In order to increase the efficacy of MSC transplantation, it is thus imperative to completely characterise the mechanisms mediating neuroinflammation and cell death following MSC transplantation into the CNS. Consequently, different components of these cell death- and neuroinflammation-inducing pathways can be targeted in an attempt to improve the therapeutic potential of MSCs for CNS disorders.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/fisiología , Sistema Nervioso Central , Humanos , Células Madre Mesenquimatosas/patología
17.
Methods Mol Biol ; 1052: 125-41, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23733539

RESUMEN

Stem cell transplantation in the central nervous system (CNS) is currently under intensive investigation as a novel therapeutic approach for a variety of brain disorders and/or injuries. However, one of the main hurdles at the moment is the lack of standardized procedures to evaluate cell graft survival and behavior following transplantation into CNS tissue, thereby leading to the publication of confusing and/or conflicting research results. In this chapter, we therefore provide validated in vivo bioluminescence and postmortem histological procedures to quantitatively determine: (a) the survival of grafted stem cells, and (b) the microglial and astroglial cell responses following cell grafting.


Asunto(s)
Sistema Nervioso Central/citología , Mediciones Luminiscentes/métodos , Trasplante de Células Madre Mesenquimatosas , Células-Madre Neurales/trasplante , Animales , Astrocitos/citología , Diferenciación Celular , Supervivencia Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Células Cultivadas , Supervivencia de Injerto , Células Madre Mesenquimatosas/citología , Ratones , Microglía/citología , Células-Madre Neurales/citología , Neuronas/metabolismo , Oligodendroglía/metabolismo
18.
PLoS One ; 8(12): e84241, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24358348

RESUMEN

INTRODUCTION: Functional connectivity (FC) studies have gained immense popularity in the evaluation of several neurological disorders, such as Alzheimer's disease (AD). AD is a complex disorder, characterised by several pathological features. The problem with FC studies in patients is that it is not straightforward to focus on a specific aspect of pathology. In the current study, resting state functional magnetic resonance imaging (rsfMRI) is applied in a mouse model of amyloidosis to assess the effects of amyloid pathology on FC in the mouse brain. METHODS: Nine APP/PS1 transgenic and nine wild-type mice (average age 18.9 months) were imaged on a 7T MRI system. The mice were anesthetized with medetomidine and rsfMRI data were acquired using a gradient echo EPI sequence. The data were analysed using a whole brain seed correlation analysis and interhemispheric FC was evaluated using a pairwise seed analysis. Qualitative histological analyses were performed to assess amyloid pathology, inflammation and synaptic deficits. RESULTS: The whole brain seed analysis revealed an overall decrease in FC in the brains of transgenic mice compared to wild-type mice. The results showed that interhemispheric FC was relatively preserved in the motor cortex of the transgenic mice, but decreased in the somatosensory cortex and the hippocampus when compared to the wild-type mice. The pairwise seed analysis confirmed these results. Histological analyses confirmed the presence of amyloid pathology, inflammation and synaptic deficits in the transgenic mice. CONCLUSIONS: In the current study, rsfMRI demonstrated decreased FC in APP/PS1 transgenic mice compared to wild-type mice in several brain regions. The APP/PS1 transgenic mice had advanced amyloid pathology across the brain, as well as inflammation and synaptic deficits surrounding the amyloid plaques. Future studies should longitudinally evaluate APP/PS1 transgenic mice and correlate the rsfMRI findings to specific stages of amyloid pathology.


Asunto(s)
Amiloidosis/fisiopatología , Mapeo Encefálico , Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Amiloidosis/metabolismo , Amiloidosis/patología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Modelos Animales de Enfermedad , Masculino , Ratones
19.
Immunobiology ; 218(5): 696-705, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22944251

RESUMEN

Although cell transplantation is increasingly suggested to be beneficial for the treatment of various neurodegenerative diseases, the therapeutic application of such intervention is currently hindered by the limited knowledge regarding central nervous system (CNS) transplantation immunology. In this study, we aimed to investigate the early post transplantation innate immune events following grafting of autologous mesenchymal stromal cells (MSC) in the CNS of immune competent mice. First, the survival of grafted Luciferase/eGFP-expressing MSC (MSC-Luc/eGFP) was demonstrated to be stable from on day 3 post implantation using in vivo bioluminescence imaging (BLI), which was further confirmed by quantitative histological analysis of MSC-Luc/eGFP graft survival. Additional histological analyses at week 1 and week 2 post grafting revealed the appearance of (i) graft-surrounding/-invading Iba1+ microglia and (ii) graft-surrounding GFAP+ astrocytes, as compared to day 0 post grafting. While the density of graft-surrounding astrocytes and microglia did not change between week 1 and week 2 post grafting, the density of graft-invading microglia significantly decreased between week 1 and week 2 post implantation. However, despite the observed decrease in microglial density within the graft site, additional phenotypic analysis of graft-invading microglia, based on CD11b- and MHCII-expression, revealed >50% of graft-invading microglia at week 2 post implantation to display an activated status. Although microglial expression of CD11b and MHCII is already suggestive for a pro-inflammatory M1-oriented phenotype, the latter was further confirmed by: (i) the expression of NOS2 by microglia within the graft site, and (ii) the absence of arginase 1-expression, an enzyme known to suppress NO activity in M2-oriented microglia, on graft-surrounding and -invading microglia. In summary, we here provide a detailed phenotypic analysis of post transplantation innate immune events in the CNS of mice, and warrant that such intervention is associated with an M1-oriented microglia response and severe astrogliosis.


Asunto(s)
Astrocitos/citología , Encéfalo/citología , Supervivencia de Injerto/inmunología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Microglía/citología , Animales , Astrocitos/inmunología , Encéfalo/inmunología , Antígeno CD11b/genética , Antígeno CD11b/inmunología , Recuento de Células , Células Cultivadas , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes , Luciferasas , Masculino , Células Madre Mesenquimatosas/inmunología , Ratones , Ratones Transgénicos , Microglía/inmunología , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/inmunología , Trasplante Autólogo
20.
Stem Cell Rev Rep ; 8(1): 262-78, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21537994

RESUMEN

Transplantation of neural stem cells (NSC) is hoped to become a promising primary or secondary therapy for the treatment of various neurodegenerative disorders of the central nervous system (CNS), as demonstrated by multiple pre-clinical animal studies in which functional recovery has already been demonstrated. However, for NSC therapy to be successful, the first challenge will be to define a transplantable cell population. In the first part of this review, we will briefly discuss the main features of ex vivo culture and characterisation of NSC. Next, NSC grafting itself may not only result in the regeneration of lost tissue, but more importantly has the potential to improve functional outcome through many bystander mechanisms. In the second part of this review, we will briefly discuss several pre-clinical studies that contributed to a better understanding of the therapeutic potential of NSC grafts in vivo. However, while many pre-clinical animal studies mainly report on the clinical benefit of NSC grafting, little is known about the actual in vivo fate of grafted NSC. Therefore, the third part of this review will focus on non-invasive imaging techniques for monitoring cellular grafts in the brain under in vivo conditions. Finally, as NSC transplantation research has evolved during the past decade, it has become clear that the host micro-environment itself, either in healthy or injured condition, is an important player in defining success of NSC grafting. The final part of this review will focus on the host environmental influence on survival, migration and differentiation of grafted NSC.


Asunto(s)
Células-Madre Neurales/fisiología , Animales , Técnicas de Cultivo de Célula , Movimiento Celular , Sistema Nervioso Central/patología , Sistema Nervioso Central/fisiopatología , Enfermedades del Sistema Nervioso Central/terapia , Humanos , Regeneración Nerviosa , Células-Madre Neurales/metabolismo , Células-Madre Neurales/trasplante , Neurogénesis , Prótesis e Implantes
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