scholarly journals FTIR Imaging of Brain Tissue Reveals Crystalline Creatine Deposits Are an ex Vivo Marker of Localized Ischemia during Murine Cerebral Malaria: General Implications for Disease Neurochemistry

2012 ◽  
Vol 3 (12) ◽  
pp. 1017-1024 ◽  
Author(s):  
Mark J. Hackett ◽  
Joonsup Lee ◽  
Fatima El-Assaad ◽  
James A. McQuillan ◽  
Elizabeth A. Carter ◽  
...  
Keyword(s):  
Cerebral Malaria ◽  
Brain Tissue ◽  
Ex Vivo ◽  
Ftir Imaging

Monocytes as Carriers of Magnetic Nanoparticles for Tracking Inflammation in the Epileptic Rat Brain

2019 ◽  
Vol 16 (7) ◽  
pp. 637-644 ◽  
Author(s):  
Hadas Han ◽  
Sara Eyal ◽  
Emma Portnoy ◽  
Aniv Mann ◽  
Miriam Shmuel ◽  
...  
Keyword(s):  
Brain Tissue ◽  
Ex Vivo ◽  
In Vivo Studies ◽  
Nanoparticle Distribution ◽  
Spontaneous Seizures ◽  
Systemic Distribution ◽  
Hippocampal Ca1 ◽  
Pilocarpine Model

Background: Inflammation is a hallmark of epileptogenic brain tissue. Previously, we have shown that inflammation in epilepsy can be delineated using systemically-injected fluorescent and magnetite- laden nanoparticles. Suggested mechanisms included distribution of free nanoparticles across a compromised blood-brain barrier or their transfer by monocytes that infiltrate the epileptic brain. Objective: In the current study, we evaluated monocytes as vehicles that deliver nanoparticles into the epileptic brain. We also assessed the effect of epilepsy on the systemic distribution of nanoparticleloaded monocytes. Methods: The in vitro uptake of 300-nm nanoparticles labeled with magnetite and BODIPY (for optical imaging) was evaluated using rat monocytes and fluorescence detection. For in vivo studies we used the rat lithium-pilocarpine model of temporal lobe epilepsy. In vivo nanoparticle distribution was evaluated using immunohistochemistry. Results: 89% of nanoparticle loading into rat monocytes was accomplished within 8 hours, enabling overnight nanoparticle loading ex vivo. The dose-normalized distribution of nanoparticle-loaded monocytes into the hippocampal CA1 and dentate gyrus of rats with spontaneous seizures was 176-fold and 380-fold higher compared to the free nanoparticles (p<0.05). Seizures were associated with greater nanoparticle accumulation within the liver and the spleen (p<0.05). Conclusion: Nanoparticle-loaded monocytes are attracted to epileptogenic brain tissue and may be used for labeling or targeting it, while significantly reducing the systemic dose of potentially toxic compounds. The effect of seizures on monocyte biodistribution should be further explored to better understand the systemic effects of epilepsy.

scholarly journals Multicellular ‘hotspots’ harbour high-grade potential in lower-grade gliomas

2021 ◽  
Author(s):  
Alastair J Kirby ◽  
José P Lavrador ◽  
Istvan Bodi ◽  
Francesco Vergani ◽  
Ranjeev Bhangoo ◽  
...  
Keyword(s):  
Human Brain ◽  
Brain Tissue ◽  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Brain Slices ◽  
Glioma Cells ◽  
Malignant Progression ◽  
Lower Grade ◽  
High Grade ◽  
Human Brain Tissue

Abstract Background Lower-grade gliomas may be indolent for many years before developing malignant behaviour. The reasons mechanisms underlying malignant progression remain unclear. Methods We collected blocks of live human brain tissue donated by people undergoing glioma resection. The tissue blocks extended through the peritumoral cortex and into the glioma. The living human brain tissue was cut into ex vivo brain slices and bathed in 5-aminolevulinic acid (5-ALA). High-grade glioma cells avidly take up 5-aminolevulinic acid (5-ALA) and accumulate high levels of the fluorescent metabolite, Protoporphyrin IX (PpIX). We exploited the PpIX fluorescence emitted by higher-grade glioma cells to investigate the earliest stages of malignant progression in lower-grade gliomas. Results We found sparsely-distributed ‘hot-spots’ of PpIX-positive cells in living lower-grade glioma tissue. Glioma cells and endothelial cells formed part of the PpIX hotspots. Glioma cells in PpIX hotspots were IDH1 mutant and expressed nestin suggesting they had acquired stem-like properties. Spatial analysis with 5-ALA conjugated quantum dots indicated that these glioma cells replicated adjacent to blood vessels. PpIX hotspots formed in the absence of angiogenesis. Conclusion Our data show that PpIX hotspots represent microdomains of cells with high-grade potential within lower-grade gliomas and identify locations where malignant progression could start.

scholarly journals Thrombospondin mediates the cytoadherence of Plasmodium falciparum- infected red cells to vascular endothelium in shear flow conditions

Blood ◽  
1988 ◽  
Vol 71 (1) ◽  
pp. 71-75
Author(s):  
EP Rock ◽  
EF Jr Roth ◽  
RR Rojas-Corona ◽  
JA Sherwood ◽  
RL Nagel ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Cerebral Malaria ◽  
Ex Vivo ◽  
Rabbit Antiserum ◽  
Immune Serum ◽  
Red Cells ◽  
Specific Attachment ◽  
Infected Cells ◽  
Human Immune ◽  
Venular Endothelium

Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria.

scholarly journals Publisher Correction: Investigation of brain tissue infiltration by medulloblastoma cells in an ex vivo model

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Anuja Neve ◽  
Karthiga Santhana Kumar ◽  
Dimitra Tripolitsioti ◽  
Michael A. Grotzer ◽  
Martin Baumgartner
Keyword(s):  
Brain Tissue ◽  
Ex Vivo ◽  
Ex Vivo Model

scholarly journals P11.57 A 3D brain organoid coculture system delineates the invasive cell components in glioblastoma

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii56-iii57
Author(s):  
W Zhou ◽  
B Klink ◽  
G Dittmar ◽  
P Nazarov ◽  
E M Garcia ◽  
...  
Keyword(s):  
Brain Tissue ◽  
Cell Invasion ◽  
Ex Vivo ◽  
Normal Brain ◽  
Rna Seq ◽  
Normal Brain Tissue ◽  
Coculture System ◽  
Mature Brain ◽  
Brain Organoid ◽  
The Brain

Abstract BACKGROUND Glioblastoma (GBM) cell infiltration into the surrounding normal brain tissue where the blood brain barrier is intact, represents a major problem for clinical management and therapy. There is a vital need to understand the molecular mechanism that drives tumor cell invasion into the surrounding brain. We have previously developed a 3D coculture model where mature brain organoids are confronted with patient-derived glioblastoma stem-like cells (GSCs). In such a coculture system, single cell invasion into the normal brain tissue can be studied in detail. Here, we first describe in detail, by RNA-seq and proteomics, the differentiation of various neural cell lineages into mature brain organoids as well as their cellular organization. By real-time confocal microscopy and imaging analyses we also determine the speed of tumor cell invasion into the brain. Finally, we used this coculture system to delineate in detail the cellular heterogeneity within the invasive compartment and their gene expression. MATERIAL AND METHODS Immunohistochemistry and immunofluorescence were used to determine the expression and distribution of mature neurons, astrocytes, oligodendrocytes, and microglia within the brain organoids. Proteomics and RNA-seq were used to determine brain development ex-vivo. To assess the clonal composition of the GBM-invasive compartment, we used cellular (RGB) barcoding technology. By advanced imaging, we tracked in real time the invasion of barcoded cells into the brain organoids. Finally, we isolated invasive cells and non-invasive cells from our coculture system and used single cell sequencing to analyze their gene expression profiles and molecular phenotypes. RESULTS Immunohistochemistry and immunofluorescence showed that brain organoids, after 21 days of differentiation, display a highly cellular and structural organization. RNA-seq and proteomics, performed at different time points of organoid differentiation, revealed that the brain organoids develop into mature brain structures after 21 days as verified by a comparative analysis to normal rat brain development in vivo. Imaging analyses showed that multiple clones within the GBMs have the capacity to invade into the brain tissue with an average speed of ~ 20 μm/h. RNA-sec analysis of the invasive compartment revealed a strong up-regulation of genes and pathways associated with anaerobic respiration (glycolysis). CONCLUSION We describe a highly standardized brain organoid coculture system that can be used to delineate GBM invasion ex-vivo. We demonstrate that this platform can be used to unravel the mechanisms that drive GBM invasion into the normal brain.

Imaging of Aβ-deposits in ex-vivo Alzheimer's disease brain tissue using Raman spectroscopy (Conference Presentation)

2019 ◽  
Author(s):  
Benjamin Lochocki ◽  
Tjado H. J. Morrema ◽  
Jurre den Haan ◽  
Freek Ariese ◽  
Femke H. Bouwman ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Raman Spectroscopy ◽  
Brain Tissue ◽  
Ex Vivo

scholarly journals Modelling heme-mediated brain injury associated with cerebral malaria in human brain cortical organoids

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Adriana Harbuzariu ◽  
Sidney Pitts ◽  
Juan Carlos Cespedes ◽  
Keri Oxendine Harp ◽  
Annette Nti ◽  
...  
Keyword(s):  
Brain Injury ◽  
Cerebral Malaria ◽  
Structural Changes ◽  
Ex Vivo ◽  
Human Subjects ◽  
Neuroprotective Effect ◽  
Three Dimensional ◽  
Free Heme ◽  
Tyrosine Protein Kinase ◽  
Induced Pluripotent

AbstractHuman cerebral malaria (HCM), a severe encephalopathy associated with Plasmodium falciparum infection, has a 20–30% mortality rate and predominantly affects African children. The mechanisms mediating HCM-associated brain injury are difficult to study in human subjects, highlighting the urgent need for non-invasive ex vivo human models. HCM elevates the systemic levels of free heme, which damages the blood-brain barrier and neurons in distinct regions of the brain. We determined the effects of heme on induced pluripotent stem cells (iPSCs) and a three-dimensional cortical organoid system and assessed apoptosis and differentiation. We evaluated biomarkers associated with heme-induced brain injury, including a pro-inflammatory chemokine, CXCL-10, and its receptor, CXCR3, brain-derived neurotrophic factor (BDNF) and a receptor tyrosine-protein kinase, ERBB4, in the organoids. We then tested the neuroprotective effect of neuregulin-1 (NRG-1) against heme treatment in organoids. Neural stem and mature cells differentially expressed CXCL-10, CXCR3, BDNF and ERBB4 in the developing organoids and in response to heme-induced neuronal injury. The organoids underwent apoptosis and structural changes that were attenuated by NRG-1. Thus, cortical organoids can be used to model heme-induced cortical brain injury associated with HCM pathogenesis as well as for testing agents that reduce brain injury and neurological sequelae.

scholarly journals Common Strategies To Prevent and Modulate Experimental Cerebral Malaria in Mouse Strains with Different Susceptibilities

2008 ◽  
Vol 76 (7) ◽  
pp. 3312-3320 ◽  
Author(s):  
Louise M. Randall ◽  
Fiona H. Amante ◽  
Karli A. McSweeney ◽  
Yonghong Zhou ◽  
Amanda C. Stanley ◽  
...  
Keyword(s):  
T Cells ◽  
Cerebral Malaria ◽  
Brain Tissue ◽  
Expression Profiles ◽  
Susceptibility Gene ◽  
Treg Cells ◽  
Mouse Strains ◽  
Significant Heterogeneity ◽  
Experimental Cerebral Malaria ◽  
Cba Mice

ABSTRACT Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection, predominantly experienced by children and nonimmune adults, which results in significant mortality and long-term sequelae. Previous studies have reported distinct susceptibility gene loci in CBA/CaH (CBA) and C57BL/6 (B6) mice with experimental CM (ECM) caused by infection with Plasmodium berghei ANKA. Here we present an analysis of genome-wide expression profiles in brain tissue taken from B6 and CBA mice with ECM and report significant heterogeneity between the two mouse strains. Upon comparison of the leukocyte composition of ECM brain tissue, microglia were expanded in B6 mice but not CBA mice. Furthermore, circulating levels of gamma interferon, interleukin-10, and interleukin-6 were significantly higher in the serum of B6 mice than in that of CBA mice with ECM. Two therapeutic strategies were applied to B6 and CBA mice, i.e., (i) depletion of regulatory T (Treg) cells prior to infection and (ii) depletion of CD8+ T cells after the establishment of ECM. Despite the described differences between susceptible mouse strains, depletion of Treg cells before infection attenuated ECM in both B6 and CBA mice. In addition, the depletion of CD8+ T cells when ECM symptoms are apparent leads to abrogation of ECM in B6 mice and a lack of progression of ECM in CBA mice. These results may have important implications for the development of effective treatments for human CM.

scholarly journals Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice

2016 ◽  
Vol 37 (3) ◽  
pp. 994-1005 ◽  
Author(s):  
Lindsay S Cahill ◽  
Lisa M Gazdzinski ◽  
Albert KY Tsui ◽  
Yu-Qing Zhou ◽  
Sharon Portnoy ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Tissue ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Cell Model ◽  
Ex Vivo ◽  
Tissue Hypoxia ◽  
Brain Physiology ◽  
The Brain

Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.

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