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1.
Int J Mol Sci ; 25(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38255817

RESUMO

Demyelination in the central nervous system (CNS) resulting from injury or disease can cause loss of nerve function and paralysis. Cell therapies intended to promote remyelination of axons are a promising avenue of treatment, with mesenchymal stromal cells (MSCs) a prominent candidate. We have previously demonstrated that MSCs derived from human olfactory mucosa (hOM-MSCs) promote myelination to a greater extent than bone marrow-derived MSCs (hBM-MSCs). However, hOM-MSCs were developed using methods and materials that were not good manufacturing practice (GMP)-compliant. Before considering these cells for clinical use, it is necessary to develop a method for their isolation and expansion that is readily adaptable to a GMP-compliant environment. We demonstrate here that hOM-MSCs can be derived without enzymatic tissue digestion or cell sorting and without culture antibiotics. They grow readily in GMP-compliant media and express typical MSC surface markers. They robustly produce CXCL12 (a key secretory factor in promoting myelination) and are pro-myelinating in in vitro rodent CNS cultures. GMP-compliant hOM-MSCs are comparable in this respect to those grown in non-GMP conditions. However, when assessed in an in vivo model of demyelinating disease (experimental autoimmune encephalitis, EAE), they do not significantly improve disease scores compared with controls, indicating further pre-clinical evaluation is necessary before their advancement to clinical trials.


Assuntos
Antibacterianos , Células-Tronco Mesenquimais , Humanos , Técnicas de Cultura , Axônios , Transporte Biológico
2.
Biology (Basel) ; 12(3)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36979099

RESUMO

Therapies that target the multicellular pathology of central nervous system (CNS) disease/injury are urgently required. Modified non-anticoagulant heparins mimic the heparan sulphate (HS) glycan family and have been proposed as therapeutics for CNS repair since they are effective regulators of numerous cellular processes. Our in vitro studies have demonstrated that low-sulphated modified heparan sulphate mimetics (LS-mHeps) drive CNS repair. However, LS-mHeps are derived from pharmaceutical heparin purified from pig intestines, in a supply chain at risk of shortages and contamination. Alternatively, cellular synthesis of heparin and HS can be achieved using mammalian cell multiplex genome engineering, providing an alternative source of recombinant HS mimetics (rHS). TEGA Therapeutics (San Diego) have manufactured rHS reagents with varying degrees of sulphation and we have validated their ability to promote repair in vitro using models that mimic CNS injury, making comparisons to LS-mHep7, a previous lead compound. We have shown that like LS-mHep7, low-sulphated rHS compounds promote remyelination and reduce features of astrocytosis, and in contrast, highly sulphated rHS drive neurite outgrowth. Cellular production of heparin mimetics may, therefore, offer potential clinical benefits for CNS repair.

3.
Glia ; 71(7): 1683-1698, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36945189

RESUMO

There is an urgent need for therapies that target the multicellular pathology of central nervous system (CNS) disease. Modified, nonanticoagulant heparins mimic the heparan sulfate glycan family and are known regulators of multiple cellular processes. In vitro studies have demonstrated that low sulfated modified heparin mimetics (LS-mHeps) drive repair after CNS demyelination. Herein, we test LS-mHep7 (an in vitro lead compound) in experimental autoimmune encephalomyelitis (EAE) and cuprizone-induced demyelination. In EAE, LS-mHep7 treatment resulted in faster recovery and rapidly reduced inflammation which was accompanied by restoration of animal weight. LS-mHep7 treatment had no effect on remyelination or on OLIG2 positive oligodendrocyte numbers within the corpus callosum in the cuprizone model. Further in vitro investigation confirmed that LS-mHep7 likely mediates its pro-repair effect in the EAE model by sequestering inflammatory cytokines, such as CCL5 which are upregulated during immune-mediated inflammatory attacks. These data support the future clinical translation of this next generation modified heparin as a treatment for CNS diseases with active immune system involvement.


Assuntos
Doenças do Sistema Nervoso Central , Encefalomielite Autoimune Experimental , Animais , Camundongos , Cuprizona/toxicidade , Sulfatos/efeitos adversos , Oligodendroglia/patologia , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Corpo Caloso/patologia , Doenças do Sistema Nervoso Central/patologia , Heparitina Sulfato/uso terapêutico , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Bainha de Mielina/patologia
4.
Front Mol Neurosci ; 15: 860410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493328

RESUMO

Zika virus (ZIKV) is a neurotropic flavivirus recently linked to congenital ZIKV syndrome in children and encephalitis and Guillain-Barré syndrome in adults. Neurotropic viruses often use axons to traffic to neuronal or glial cell somas where they either remain latent or replicate and proceed to infect new cells. Consequently, it has been suggested that axon degeneration could represent an evolutionarily conserved mechanism to limit viral spread. Whilst it is not known if ZIKV transits in axons, we previously reported that ZIKV infection of glial cells in a murine spinal cord-derived cell culture model of the CNS is associated with a profound loss of neuronal cell processes. This, despite that postmitotic neurons are relatively refractory to infection and death. Here, we tested the hypothesis that ZIKV-associated degeneration of neuronal processes is dependent on activation of Sterile alpha and armadillo motif-containing protein 1 (SARM1), an NADase that acts as a central executioner in a conserved axon degeneration pathway. To test this, we infected wild type and Sarm1 homozygous or heterozygous null cell cultures with ZIKV and examined NAD+ levels as well as the survival of neurons and their processes. Unexpectedly, ZIKV infection led to a rapid SARM1-independent reduction in NAD+. Nonetheless, the subsequent profound loss of neuronal cell processes was SARM1-dependent and was preceded by early changes in the appearance of ß-tubulin III staining. Together, these data identify a role for SARM1 in the pathogenesis of ZIKV infection, which may reflect SARM1's conserved prodegenerative function, independent of its NADase activity.

5.
Methods Mol Biol ; 2429: 333-344, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507171

RESUMO

Striatum-derived neural stem cells have been used to generate a variety of neural cell populations. They are composed of free-floating clusters of clonal neural stem cells, termed neurospheres, and can be expanded under growth factor stimulation in vitro. The multipotent nature of neurospheres means that under certain growth conditions they can differentiate into neuronal and glial progenitors of the central nervous system (CNS).Here, we describe a method for creating a population of astrocytes derived from rat striatum neurospheres, which in turn can be used to generate astrocytes with different reactivity phenotypes. Several methods and techniques are already available for the generation of neurospheres, but the method detailed herein provides an accessible, reproducible protocol for large numbers of astrocyte cultures, that can then be manipulated in an experimental format for further investigation.


Assuntos
Astrócitos , Células-Tronco Neurais , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Imuno-Histoquímica , Fenótipo , Ratos
6.
Exp Neurol ; 354: 114113, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35569511

RESUMO

Iron released from oligodendrocytes during demyelination or derived from haemoglobin breakdown products is believed to amplify oxidative tissue injury in multiple sclerosis (MS). However, the pathophysiological significance of iron-containing haemoglobin breakdown products themselves is rarely considered in the context of MS and their cellular specificity and mode of action remain unclear. Using myelinating cell cultures, we now report the cytotoxic potential of hemin (ferriprotoporphyrin IX chloride), a major degradation product of haemoglobin, is 25-fold greater than equimolar concentrations of free iron in myelinating cultures; a model that reproduces the complex multicellular environment of the CNS. At low micro molar concentrations (3.3 - 10 µM) we observed hemin preferentially binds to myelin and axons to initiate a complex detrimental response that results in targeted demyelination and axonal loss but spares neuronal cell bodies, astrocytes and the majority of oligodendroglia. Demyelination and axonal loss in this context are executed by a combination of mechanisms that include iron-dependent peroxidation by reactive oxygen species (ROS) and ferroptosis. These effects are microglial-independent, do not require any initiating inflammatory insult and represent a direct effect that compromises the structural integrity of myelinated axons in the CNS. Our data identify hemin-mediated demyelination and axonal loss as a novel mechanism by which intracerebral degradation of haemoglobin may contribute to lesion development in MS.


Assuntos
Hemina , Esclerose Múltipla , Axônios/patologia , Sistema Nervoso Central/patologia , Hemina/metabolismo , Hemina/farmacologia , Humanos , Ferro/metabolismo , Esclerose Múltipla/patologia , Bainha de Mielina/patologia , Oligodendroglia/metabolismo , Estresse Oxidativo
7.
Acta Neuropathol Commun ; 10(1): 12, 2022 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093166

RESUMO

One of the therapeutic approaches for the treatment of the autoimmune demyelinating disease, multiple sclerosis (MS) is bone marrow mesenchymal stromal cell (hBM-MSCs) transplantation. However, given their capacity to enhance myelination in vitro, we hypothesised that human olfactory mucosa-derived MSCs (hOM-MSCs) may possess additional properties suitable for CNS repair. Herein, we have examined the efficacy of hOM-MSCs versus hBM-MSCs using the experimental autoimmune encephalomyelitis (EAE) model. Both MSC types ameliorated disease, if delivered during the initial onset of symptomatic disease. Yet, only hOM-MSCs improved disease outcome if administered during established disease when animals had severe neurological deficits. Histological analysis of spinal cord lesions revealed hOM-MSC transplantation reduced blood-brain barrier disruption and inflammatory cell recruitment and enhanced axonal survival. At early time points post-hOM-MSC treatment, animals had reduced levels of circulating IL-16, which was reflected in both the ability of immune cells to secrete IL-16 and the level of IL-16 in spinal cord inflammatory lesions. Further in vitro investigation revealed an inhibitory role for IL-16 on oligodendrocyte differentiation and myelination. Moreover, the availability of bioactive IL-16 after demyelination was reduced in the presence of hOM-MSCs. Combined, our data suggests that human hOM-MSCs may have therapeutic benefit in the treatment of MS via an IL-16-mediated pathway, especially if administered during active demyelination and inflammation.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Interleucina-16/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Bainha de Mielina/metabolismo , Mucosa Olfatória/citologia , Animais , Encefalomielite Autoimune Experimental/metabolismo , Humanos , Camundongos , Neurogênese/fisiologia
8.
Glia ; 69(8): 2023-2036, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942402

RESUMO

Some children with proven intrauterine Zika virus (ZIKV) infection who were born asymptomatic subsequently manifested neurodevelopmental delays, pointing to impairment of development perinatally and postnatally. To model this, we infected postnatal day (P) 5-6 (equivalent to the perinatal period in humans) susceptible mice with a mammalian cell-propagated ZIKV clinical isolate from the Brazilian outbreak in 2015. All infected mice appeared normal up to 4 days post-intraperitoneal inoculation (dpi), but rapidly developed severe clinical signs at 5-6 dpi. All nervous tissue examined at 5/6 dpi appeared grossly normal. However, anti-ZIKV positive cells were observed in the optic nerve, brain, and spinal cord; predominantly in white matter. Co-labeling with cell type specific markers demonstrated oligodendrocytes and astrocytes support productive infection. Rarely, ZIKV positive neurons were observed. In spinal cord white matter, which we examined in detail, apoptotic cells were evident; the density of oligodendrocytes was significantly reduced; and there was localized microglial reactivity including expression of the NLRP3 inflammasome. Together, our observations demonstrate that a clinically relevant ZIKV isolate can directly impact oligodendrocytes. As primary oligodendrocyte cell death can lead later to secondary autoimmune demyelination, our observations may help explain neurodevelopmental delays in infants appearing asymptomatic at birth and commend lifetime surveillance.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Neurônios , Oligodendroglia , Gravidez , Infecção por Zika virus/complicações
9.
Cells ; 10(4)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919910

RESUMO

The use of mesenchymal stem/stromal cells (MSCs) for transplant-mediated repair represents an important and promising therapeutic strategy after spinal cord injury (SCI). The appeal of MSCs has been fuelled by their ease of isolation, immunosuppressive properties, and low immunogenicity, alongside the large variety of available tissue sources. However, despite reported similarities in vitro, MSCs sourced from distinct tissues may not have comparable biological properties in vivo. There is accumulating evidence that stemness, plasticity, immunogenicity, and adaptability of stem cells is largely controlled by tissue niche. The extrinsic impact of cellular niche for MSC repair potential is therefore important, not least because of its impact on ex vivo expansion for therapeutic purposes. It is likely certain niche-targeted MSCs are more suited for SCI transplant-mediated repair due to their intrinsic capabilities, such as inherent neurogenic properties. In addition, the various MSC anatomical locations means that differences in harvest and culture procedures can make cross-comparison of pre-clinical data difficult. Since a clinical grade MSC product is inextricably linked with its manufacture, it is imperative that cells can be made relatively easily using appropriate materials. We discuss these issues and highlight the importance of identifying the appropriate niche-specific MSC type for SCI repair.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Regeneração Nervosa/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Nicho de Células-Tronco , Humanos
10.
Viruses ; 13(1)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440758

RESUMO

Understanding how Zika virus (Flaviviridae; ZIKV) affects neural cells is paramount in comprehending pathologies associated with infection. Whilst the effects of ZIKV in neural development are well documented, impact on the adult nervous system remains obscure. Here, we investigated the effects of ZIKV infection in established mature myelinated central nervous system (CNS) cultures. Infection incurred damage to myelinated fibers, with ZIKV-positive cells appearing when myelin damage was first detected as well as axonal pathology, suggesting the latter was a consequence of oligodendroglia infection. Transcriptome analysis revealed host factors that were upregulated during ZIKV infection. One such factor, CCL5, was validated in vitro as inhibiting myelination. Transferred UV-inactivated media from infected cultures did not damage myelin and axons, suggesting that viral replication is necessary to induce the observed effects. These data show that ZIKV infection affects CNS cells even after myelination-which is critical for saltatory conduction and neuronal function-has taken place. Understanding the targets of this virus across developmental stages including the mature CNS, and the subsequent effects of infection of cell types, is necessary to understand effective time frames for therapeutic intervention.


Assuntos
Axônios/virologia , Doenças Desmielinizantes/etiologia , Infecção por Zika virus/complicações , Infecção por Zika virus/virologia , Zika virus/fisiologia , Animais , Biomarcadores , Traumatismos dos Nervos Cranianos/etiologia , Traumatismos dos Nervos Cranianos/metabolismo , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Camundongos , Ratos , Transcriptoma
11.
Biomater Sci ; 8(13): 3611-3627, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32515439

RESUMO

The limited regenerative capacity of the CNS poses formidable challenges to the repair of spinal cord injury (SCI). Two key barriers to repair are (i) the physical gap left by the injury, and (ii) the inhibitory milieu surrounding the injury, the glial scar. Biomaterial implantation into the injury site can fill the cavity, provide a substrate for cell migration, and potentially attenuate the glial scar. We investigated the biological viability of a biocompatible and biodegradable poly-ε-lysine based biomaterial, Proliferate®, in low and high cross-linked forms and when coated with IKVAV peptide, for SCI implantation. We demonstrate altered astrocyte morphology and nestin expression on Proliferate® compared to conventional glass cell coverslips suggesting a less reactive phenotype. Moreover Proliferate® supported myelination in vitro, with myelination observed sooner on IKVAV-coated constructs compared with uncoated Proliferate®, and delayed overall compared with maintenance on glass coverslips. For in vivo implantation, parallel-aligned channels were fabricated into Proliferate® to provide cell guidance cues. Extensive vascularisation and cellular infiltration were observed in constructs implanted in vivo, along with an astrocyte border and microglial response. Axonal ingrowth was observed at the construct border and inside implants in intact channels. We conclude that Proliferate® is a promising biomaterial for implantation following SCI.


Assuntos
Materiais Biocompatíveis/química , Doenças do Sistema Nervoso Central/terapia , Polilisina/química , Próteses e Implantes , Traumatismos da Medula Espinal/terapia , Animais , Materiais Biocompatíveis/síntese química , Células Cultivadas , Polilisina/síntese química , Ratos , Ratos Sprague-Dawley
12.
Spinal Cord ; 58(8): 844-856, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32249830

RESUMO

INTRODUCTION: Spinal cord injury (SCI) is associated with significant and life-long disability. Yet, despite decades of research, no regenerative treatment has reached clinical practice. Cell-based therapies are one possible regenerative strategy beginning to transfer to human trials from a more extensive pre-clinical basis. METHODS: We therefore conducted a scoping review to synthesise all cell-based trials in SCI to consider the current state of the field and the cell transplant type or strategy with greatest promise. A search strategy of MEDLINE returned 1513 results. All clinical trials including adult human patients with acute or chronic, compete or incomplete SCI and a recorded ASIA score were sought. Exclusion criteria included non-traumatic SCI, paediatric patients and animal studies. A total of 43 studies, treating 1061 patients, were identified. Most trials evaluated cells from the bone marrow (22 papers, 660 patients) or the olfactory bulb (10 papers, 245 patients). RESULTS: Cell transplantation does appear to be safe, with no serious adverse effects being reported in the short-term. 86% of trials described efficacy as a primary outcome. However, varying degrees of outcome reporting prevented meta-analysis. No emerging cell type or technique was identified. The majority of trials, 53%, took place in developing countries, which may suggest more stringent regulatory requirements within Western countries. CONCLUSION: We believe cell-based transplantation translation remains in its infancy and that, although further robust clinical research is required, it is an important strategy to consider in the treatment of SCI.


Assuntos
Transplante de Células , Avaliação de Resultados em Cuidados de Saúde , Traumatismos da Medula Espinal/terapia , Transplante de Células/efeitos adversos , Transplante de Células/estatística & dados numéricos , Humanos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos
13.
Nat Rev Neurol ; 16(4): 229-240, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32099190

RESUMO

Spinal cord injury (SCI) remains one of the biggest challenges in the development of neuroregenerative therapeutics. Cell transplantation is one of numerous experimental strategies that have been identified and tested for efficacy at both preclinical and clinical levels in recent years. In this Review, we briefly discuss the state of human olfactory cell transplantation as a therapy, considering both its current clinical status and its limitations. Furthermore, we introduce a mesenchymal stromal cell derived from human olfactory tissue, which has the potential to induce multifaceted reparative effects in the environment within and surrounding the lesion. We argue that no single therapy will be sufficient to treat SCI effectively and that a combination of cell-based, rehabilitation and pharmaceutical interventions is the most promising approach to aid repair. For this reason, we also introduce a novel pharmaceutical strategy based on modifying the activity of heparan sulfate, an important regulator of a wide range of biological cell functions. The multi-target approach that is exemplified by these types of strategies will probably be necessary to optimize SCI treatment.


Assuntos
Heparitina Sulfato/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Mucosa Olfatória/citologia , Traumatismos da Medula Espinal/terapia , Regeneração da Medula Espinal , Transplante de Células/métodos , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Heparina/uso terapêutico , Heparitina Sulfato/análogos & derivados , Humanos , Células-Tronco Mesenquimais/citologia , Regeneração Nervosa , Neuroglia , Mucosa Olfatória/fisiologia , Neurônios Receptores Olfatórios
14.
Glob Health Action ; 12(1): 1666566, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31640505

RESUMO

Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN`s mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network.


Assuntos
Surtos de Doenças/prevenção & controle , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle , América , Brasil , Fortalecimento Institucional/organização & administração , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/prevenção & controle , Feminino , Acesso aos Serviços de Saúde/organização & administração , Humanos , Recém-Nascido , Controle de Mosquitos/organização & administração , Vigilância da População , Gravidez , Zika virus , Infecção por Zika virus/diagnóstico
15.
Biology (Basel) ; 8(3)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261710

RESUMO

In vitro cell-based assays have been fundamental in modern drug discovery and have led to the identification of novel therapeutics. We have developed complex mixed central nervous system (CNS) cultures, which recapitulate the normal process of myelination over time and allow the study of several parameters associated with CNS damage, both during development and after injury or disease. In particular, they have been used as a reliable screen to identify drug candidates that may promote (re)myelination and/or neurite outgrowth. Previously, using these cultures, we demonstrated that a panel of low sulphated heparin mimetics, with structures similar to heparan sulphates (HSs), can reduce astrogliosis, and promote myelination and neurite outgrowth. HSs reside in either the extracellular matrix or on the surface of cells and are thought to modulate cell signaling by both sequestering ligands, and acting as co-factors in the formation of ligand-receptor complexes. In this study, we have used these cultures as a screen to address the repair potential of numerous other commercially available sulphated glycomolecules, namely heparosans, ulvans, and fucoidans. These compounds are all known to have certain characteristics that mimic cellular glycosaminoglycans, similar to heparin mimetics. We show that the N-sulphated heparosans promoted myelination. However, O-sulphated heparosans did not affect myelination but promoted neurite outgrowth, indicating the importance of structure in HS function. Moreover, neither highly sulphated ulvans nor fucoidans had any effect on remyelination but CX-01, a low sulphated porcine intestinal heparin, promoted remyelination in vitro. These data illustrate the use of myelinating cultures as a screen and demonstrate the potential of heparin mimetics as CNS therapeutics.

16.
Bioinformatics ; 35(21): 4528-4530, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31095292

RESUMO

SUMMARY: MyelinJ is a free user friendly ImageJ macro for high throughput analysis of fluorescent micrographs such as 2D-myelinating cultures and statistical analysis using R. MyelinJ can analyse single images or complex experiments with multiple conditions, where the ggpubr package in R is automatically used for statistical analysis and the production of publication quality graphs. The main outputs are percentage (%) neurite density and % myelination. % neurite density is calculated using the normalize local contrast algorithm, followed by thresholding, to adjust for differences in intensity. For % myelination the myelin sheaths are selected using the Frangi vesselness algorithm, in conjunction with a grey scale morphology filter and the removal of cell bodies using a high intensity mask. MyelinJ uses a simple graphical user interface and user name system for reproducibility and sharing that will be useful to the wider scientific community that study 2D-myelination in vitro. AVAILABILITY AND IMPLEMENTATION: MyelinJ is freely available at https://github.com/BarnettLab/MyelinJ. For statistical analysis the freely available R and the ggpubr package are also required. MyelinJ has a user guide (Supplementary Material) and has been tested on both Windows (Windows 10) and Mac (High Sierra) operating systems. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Software , Neuritos , Reprodutibilidade dos Testes
17.
F1000Res ; 8: 117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31069065

RESUMO

The normal development and maintenance of CNS white matter, and its responses to disease and injury, are defined by synergies between axons, oligodendrocytes, astrocytes and microglia, and further influenced by peripheral components such as the gut microbiome and the endocrine and immune systems. Consequently, mechanistic insights, therapeutic approaches and safety tests rely ultimately on in vivo models and clinical trials. However, in vitro models that replicate the cellular complexity of the CNS can inform these approaches, reducing costs and minimising the use of human material or experimental animals; in line with the principles of the 3Rs. Using electrophysiology, pharmacology, time-lapse imaging, and immunological assays, we demonstrate that murine spinal cord-derived myelinating cell cultures recapitulate spinal-like electrical activity and innate CNS immune functions, including responses to disease-relevant myelin debris and pathogen associated molecular patterns (PAMPs).  Further, we show they are (i) amenable to siRNA making them suitable for testing gene-silencing strategies; (ii) can be established on microelectrode arrays (MEAs) for electrophysiological studies; and (iii) are compatible with multi-well microplate formats for semi-high throughput screens, maximising information output whilst further reducing animal use. We provide protocols for each of these. Together, these advances increase the utility of this in vitro tool for studying normal and pathological development and function of white matter, and for screening therapeutic molecules or gene targets for diseases such as multiple sclerosis, motor neuron disease or spinal cord injury, whilst avoiding in vivo approaches on experimental animals.


Assuntos
Modelos Biológicos , Esclerose Múltipla , Traumatismos da Medula Espinal , Substância Branca , Animais , Axônios , Humanos , Camundongos , Bainha de Mielina
18.
Glia ; 67(4): 668-687, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30585359

RESUMO

The lack of endogenous repair following spinal cord injury (SCI) accounts for the frequent permanent deficits for which effective treatments are absent. Previously, we demonstrated that low sulfated modified heparin mimetics (LS-mHeps) attenuate astrocytosis, suggesting they may represent a novel therapeutic approach. mHeps are glycomolecules with structural similarities to resident heparan sulfates (HS), which modulate cell signaling by both sequestering ligands, and acting as cofactors in the formation of ligand-receptor complexes. To explore whether mHeps can affect the myelination and neurite outgrowth necessary for repair after SCI, we created lesioned or demyelinated neural cell co-cultures and exposed them with a panel of mHeps with varying degrees and positions of their sulfate moieties. LS-mHep7 enhanced neurite outgrowth and myelination, whereas highly sulfated mHeps (HS-mHeps) had attenuating effects. LS-mHeps had no effects on myelination or neurite extension in developing, uninjured myelinating cultures, suggesting they might exert their proregenerating effects by modulating or sequestering inhibitory factors secreted after injury. To investigate this, we examined conditioned media from cultures using chemokine arrays and conducted an unbiased proteomics approach by applying TMT-LC/MS to mHep7 affinity purified conditioned media from these cultures. Multiple protein factors reported to play a role in damage or repair mechanisms were identified, including amyloid betaA4. Amyloid beta peptide (1-42) was validated as an important candidate by treating myelination cultures and shown to inhibit myelination. Thus, we propose that LS-mHeps exert multiple beneficial effects on mechanisms supporting enhanced repair, and represent novel candidates as therapeutics for CNS damage.


Assuntos
Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/metabolismo , Doenças Desmielinizantes/tratamento farmacológico , Heparitina Sulfato/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Animais Recém-Nascidos , Antimetabólitos/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Desoxiuridina/farmacologia , Embrião de Mamíferos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas da Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito/metabolismo , Neuritos/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Medula Espinal/citologia
19.
Global health action, v. 12, n. 1, p. 1666566, oct. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2866

RESUMO

Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN's mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network.

20.
Global health action ; 12(1): 1666566, 2019.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17261

RESUMO

Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN's mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network.

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