In vitro models of microglia: a comparative study.

Microglia perform key homeostatic functions to protect the central nervous system (CNS). However, in many brain disorders their protective functions are abrogated, contributing to disease progression. Therefore, studies of microglial function are critical to developing treatments for brain disorders.

Heterogeneity in pericyte inflammatory responses across age and species highlight the importance of human cell models.

Pericytes in the central nervous system are essential for maintaining blood-brain barrier function, regulating blood flow, modulating immune responses, and interacting closely with surrounding cells of the neurovascular unit to support brain homeostasis. Increasing evidence has highlighted their involvement in age-related neuroinflammation, where their dysfunction may contribute to sustained inflammatory states associated with neurodegenerative disorders. Here, we compared inflammatory responses to lipopolysaccharide (LPS) in primary cerebral pericytes from neonatal and adult mice and adult humans.

Phenotypic approaches for CNS drugs.

Central nervous system (CNS) drug development is plagued by high clinical failure rate. Phenotypic assays promote clinical translation of drugs by reducing complex brain diseases to measurable, clinically valid phenotypes. We critique recent platforms integrating patient-derived brain cells, which most accurately recapitulate CNS disease phenotypes, with higher throughput models, including immortalized cells, to balance validity and scalability.

Measurement of blood-brain barrier water exchange rate using diffusion-prepared and multi-echo arterial spin labelling: Comparison of quantitative values and age dependence.

Water exchange rate (Kw) across the blood-brain barrier (BBB) is an important physiological parameter that may provide new insight into ageing and neurodegenerative disease. Recently, two non-invasive arterial spin labelling (ASL) MRI methods have been developed to measure Kw, but results from the different methods have not been directly compared. Furthermore, the association of Kw with age for each method has not been investigated in a single cohort.

Ultrastructural localization of Porphyromonas gingivalis gingipains in the substantia nigra of Parkinson's disease brains.

Gingipains are protease virulence factors produced by Porphyromonas gingivalis, a Gram-negative bacterium best known for its role in chronic periodontitis. Gingipains were recently identified in the middle temporal gyrus of postmortem Alzheimer's disease (AD) brains, where gingipain load correlated with AD diagnosis and tau and ubiquitin pathology. Since AD and Parkinson's disease (PD) share some overlapping pathologic features, including nigral pathology and Lewy bodies, the current study explored whether gingipains are present in the substantia nigra pars compacta of PD brains.

Aggregate-prone brain regions in Parkinson's disease are rich in unique N-terminus α-synuclein conformers with high proteolysis susceptibility.

In Parkinson's disease (PD), and other α-synucleinopathies, α-synuclein (α-Syn) aggregates form a myriad of conformational and truncational variants. Most antibodies used to detect and quantify α-Syn in the human brain target epitopes within the C-terminus (residues 96-140) of the 140 amino acid protein and may fail to capture the diversity of α-Syn variants present in PD. We sought to investigate the heterogeneity of α-Syn conformations and aggregation states in the PD human brain by labelling with multiple antibodies that detect epitopes along the entire length of α-Syn.

Pericytes take up and degrade α-synuclein but succumb to apoptosis under cellular stress.

Parkinson's disease (PD) is characterised by the progressive loss of midbrain dopaminergic neurons and the presence of aggregated α-synuclein (α-syn). Pericytes and microglia, two non-neuronal cells contain α-syn in the human brain, however, their role in disease processes is poorly understood. Pericytes, found surrounding the capillaries in the brain are important for maintaining the blood-brain barrier, controlling blood flow and mediating inflammation.

Tumour infiltrating lymphocyte density differs by meningioma type and is associated with prognosis in atypical meningioma.

Tumour infiltrating lymphocyte (TIL) density is prognostically significant in various tumours, but few studies have investigated its significance in meningioma. This study aimed to investigate how TIL density differs by meningioma histology and whether it is a predictor of meningioma recurrence. We studied CD3, CD8, CD4, FOXP3 and PD-1 positive (+) TIL density in a continuous cohort of 476 meningiomas resected at Auckland Hospital between 2002 and 2011 using tissue microarrays and computer assisted image analysis.

Single-cell image analysis reveals a protective role for microglia in glioblastoma.

Background: Microglia and tumor-associated macrophages (TAMs) constitute up to half of the total tumor mass of glioblastomas. Despite these myeloid populations being ontogenetically distinct, they have been largely conflated. Recent single-cell transcriptomic studies have identified genes that distinguish microglia from TAMs.

Isolation of adult mouse microglia using their in vitro adherent properties.

Microglia are the primary innate immune effectors of the central nervous system. Although numerous protocols have been developed to isolate fetal mouse microglia, the isolation of adult mouse microglia has proven more difficult. Here, we present a simple, widely accessible protocol to isolate pure microglia cultures from 4- to 14-month-old mouse brains using their adherent properties .

fISHing with immunohistochemistry for housekeeping gene changes in Alzheimer's disease using an automated quantitative analysis workflow.

In situ hybridization (ISH) is a powerful tool that can be used to localize mRNA expression in tissue samples. Combining ISH with immunohistochemistry (IHC) to determine cell type provides cellular context of mRNA expression, which cannot be achieved with gene microarray or polymerase chain reaction. To study mRNA and protein expression on the same section we investigated the use of RNAscope® ISH in combination with fluorescent IHC on paraffin-embedded human brain tissue.

The Interplay Between Beta-Amyloid 1-42 (Aβ)-Induced Hippocampal Inflammatory Response, p-tau, Vascular Pathology, and Their Synergistic Contributions to Neuronal Death and Behavioral Deficits.

Alzheimer's disease (AD), the most common chronic neurodegenerative disorder, has complex neuropathology. The principal neuropathological hallmarks of the disease are the deposition of extracellular β-amyloid (Aβ) plaques and neurofibrillary tangles (NFTs) comprised of hyperphosphorylated tau (p-tau) protein. These changes occur with neuroinflammation, a compromised blood-brain barrier (BBB) integrity, and neuronal synaptic dysfunction, all of which ultimately lead to neuronal cell loss and cognitive deficits in AD.

Isolation and culture of functional adult human neurons from neurosurgical brain specimens.

The ability to characterize and study primary neurons isolated directly from the adult human brain would greatly advance neuroscience research. However, significant challenges such as accessibility of human brain tissue and the lack of a robust neuronal cell culture protocol have hampered its progress. Here, we describe a simple and reproducible method for the isolation and culture of functional adult human neurons from neurosurgical brain specimens, adult human neurons form a dense network and express a plethora of mature neuronal and synaptic markers.

The epidemiology of patients undergoing meningioma resection in Auckland, New Zealand, 2002 to 2011.

The incidence of meningioma is known to vary by gender and ethnicity. This study aimed to describe the epidemiological characteristics of a 10-year cohort of patients undergoing meningioma resection at Auckland City Hospital, Auckland, New Zealand. Of particular interest was whether there was any difference in meningioma incidence and recurrence rates between New Zealand Maori and Pacific Island patients compared with other ethnic groups.

Human in vitro systems for examining synaptic function and plasticity in the brain.

The human brain shows remarkable complexity in its cellular makeup and function, which are distinct from nonhuman species, signifying the need for human-based research platforms for the study of human cellular neurophysiology and neuropathology. However, the use of adult human brain tissue for research purposes is hampered by technical, methodological, and accessibility challenges. One of the major problems is the limited number of in vitro systems that, in contrast, are readily available from rodent brain tissue.

Assessing fibrinogen extravasation into Alzheimer's disease brain using high-content screening of brain tissue microarrays.

Background: Tissue microarrays are commonly used to evaluate disease pathology however methods to automate and quantify pathological changes are limited.

New Method: This article demonstrates the utility of the VSlide scanner (MetaSystems) for automated image acquisition from immunolabelled tissue microarray slides, and subsequent automated image analysis with MetaXpress (Molecular Devices) software to obtain objective, efficient and reproducible data from immunolabelled tissue microarray sections.

Results: Significant increases in fibrinogen immunolabelling were observed in 29 Alzheimer's disease cases compared to 28 control cases analysed from a single tissue microarray slide.

Hypothermic neuroprotection is associated with recovery of spectral edge frequency after asphyxia in preterm fetal sheep.

Background And Purpose: Electroencephalographic recovery is predictive of outcome after perinatal hypoxia-ischemia, but it is unknown whether early changes in electroencephalographic can predict the response to therapeutic hypothermia in the preterm brain.

Methods: 0.7 gestation fetal sheep received umbilical cord occlusion or sham occlusion for 25 minutes, followed by sham hypothermia or whole-body cooling started either 30 minutes or 5 hours after occlusion and continued for 72 hours.

High content analysis of histone acetylation in human cells and tissues.

There is increasing demand for automated image analysis of cell nuclei to be fast, objective and informative. Here, we have developed a high content analysis method for quantifying histone acetylation within any given population of cells. To demonstrate the utility of this method we quantified the effect of valproic acid (VPA) on histone H3 acetylation levels in SK-N-SH cells, a human neuroblastomal cell line.

M3 muscarinic receptors promote cell survival through activation of the extracellular regulated kinase (ERK1/2) pathway.

Activation of certain subtypes of the muscarinic acetylcholine receptor can enhance cell survival. In SK-N-SH human neuroblastoma cells, muscarinic acetylcholine receptor activation induces phosphorylation of CREB and induction of EGR1, transcription factors associated with cell growth and survival. We identified the M3 muscarinic acetylcholine receptor subtype as being primarily responsible for these transcription factor responses after stimulation with carbachol, using subtype-preferring receptor antagonists and muscarinic snake toxins.

High-throughput quantification of Alzheimer's disease pathological markers in the post-mortem human brain.

Quantitative analysis of amyloid plaques and neurofibrillary tangles is central to many Alzheimer's disease studies. A novel approach for quantitative immunohistochemistry of plaques and tangles has arisen from the need to account for the heterogeneous expression pattern of these markers in the human brain. This approach aims to overcome the human bias inherent to many sampling strategies, to account for the effects of tissue shrinkage resulting from antigen-retrieval procedures, and to accelerate the analysis of large sample sets by using a high-throughput quantification system.

Extracellular signal-regulated kinase involvement in human astrocyte migration.

Glial scar formation occurs after virtually any injury to the brain. The migration of astrocytes into regions of brain injury underlies the formation of the glial scar. The exact role of the glial scar has yet to be elucidated, although it is likely to impair brain recovery.

High throughput quantification of cells with complex morphology in mixed cultures.

Automated image-based and biochemical assays have greatly increased throughput for quantifying cell numbers in in vitro studies. However, it has been more difficult to automate the counting of specific cell types with complex morphologies in mixed cell cultures. We have developed a fully automated, fast, accurate and objective method for the quantification of primary human GFAP-positive astrocytes and CD45-positive microglia from images of mixed cell populations.

Human neuroblasts migrate to the olfactory bulb via a lateral ventricular extension.

The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone cells reach the olfactory bulb (OB) in rodents. However, the RMS in the adult human brain has been elusive. We demonstrate the presence of a human RMS, which is unexpectedly organized around a lateral ventricular extension reaching the OB, and illustrate the neuroblasts in it.

Activation of activating transcription factor 2 by p38 MAP kinase during apoptosis induced by human amylin in cultured pancreatic beta-cells.

Amylin-mediated islet beta-cell death is implicated in diabetogenesis. We previously reported that fibrillogenic human amylin (hA) evokes beta-cell apoptosis through linked activation of Jun N-terminal kinase 1 (JNK 1) and a caspase cascade. Here we show that p38 kinase [p38 mitogen-activated protein (MAP) kinase] became activated by hA treatment of cultured beta-cells whereas extracellular signal-regulated kinase (ERK) did not; by contrast, nonfibrillogenic rat amylin (rA) altered neither.