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We report a patient with atypical parkinsonism due to coexistent Lewy body disease (LBD) and diffuse anaplastic astrocytoma. The patient presented with a mixed cerebellar and parkinsonian syndrome, incomplete levodopa response, and autonomic failure. The clinical diagnosis was multiple system atrophy (MSA). Supportive features of MSA according to the consensus diagnostic criteria included postural instability and early falls, early dysphagia, pyramidal signs, and orofacial dystonia. Multiple exclusion criteria for a diagnosis of idiopathic Parkinson’s disease (iPD) were present.Neuropathological examination of the left hemisphere, and the whole midbrain and brainstem showed LBD, neocortical-type consistent with iPD, hippocampal sclerosis and widespread neoplastic infiltration by an anaplastic astrocytoma without evidence of a space occupying lesion. There were no pathological features of MSA.The classification of atypical parkinsonism was difficult in this patient. The clinical features and disease course were confounded by the co-existent tumour, leading to atypical presentation and a diagnosis of MSA. We suggest that the initial features were due to Lewy body pathology, while progression and ataxia, pyramidal signs and falls, were accelerated by the occurrence of the astrocytoma. Our case reflects the challenges of an accurate diagnosis of atypical parkinsonism, the potential for confounding co-pathology and the need for autopsy examination to reach a definitive diagnosis.

BackgroundPick’s disease (PiD) is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. PiD is pathologically defined by argyrophilic inclusion Pick bodies and ballooned neurons in the frontal and temporal brain lobes. PiD is characterised by the presence of Pick bodies which are formed from aggregated, hyperphosphorylated, 3-repeat tau proteins, encoded by theMAPTgene. TheMAPTH2 haplotype has consistently been associated with a decreased disease risk of the 4-repeat tauopathies of progressive supranuclear palsy and corticobasal degeneration, however its role in susceptibility to PiD is unclear. The primary aim of this study was to evaluate the association betweenMAPTH2 and risk of PiD.MethodsWe established the Pick’s disease International Consortium (PIC) and collected 338 (60.7% male) pathologically confirmed PiD brains from 39 sites worldwide. 1,312 neurologically healthy clinical controls were recruited from Mayo Clinic Jacksonville, FL (N=881) or Rochester, MN (N=431). For the primary analysis, subjects were directly genotyped forMAPTH1-H2 haplotype-defining variant rs8070723. In secondary analysis, we genotyped and constructed the six-variantMAPTH1 subhaplotypes (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521).FindingsOur primary analysis found that theMAPTH2 haplotype was associated with increased risk of PiD (OR: 1.35, 95% CI: 1.12-1.64 P=0.002). In secondary analysis involving H1 subhaplotypes, a protective association with PiD was observed for the H1f haplotype (0.0% vs. 1.2%, P=0.049), with a similar trend noted for H1b (OR: 0.76, 95% CI: 0.58-1.00, P=0.051). The 4-repeat tauopathy risk haplotypeMAPTH1c was not associated with PiD susceptibility (OR: 0.93, 95% CI: 0.70-1.25, P=0.65).InterpretationThe PIC represents the first opportunity to perform relatively large-scale studies to enhance our understanding of the pathobiology of PiD. This study demonstrates that in contrast to its protective role in 4R tauopathies, theMAPTH2 haplotype is associated with an increased risk of PiD. This finding is critical in directing isoform-related therapeutics for tauopathies.FundingSee funding section

SummaryHigh levels of proinflammatory cytokines induce neurotoxicity and catalyze inflammation-driven neurodegeneration, but the specific release mechanisms from microglia remain elusive. We demonstrate that secretory autophagy (SA), a non-lytic modality of autophagy for secretion of vesicular cargo, regulates neuroinflammation-mediated neurodegeneration via SKA2 and FKBP5 signaling. SKA2 inhibits SA-dependent IL-1β release by counteracting FKBP5 function. HippocampalSka2knockdown in mice hyperactivates SA resulting in neuroinflammation, subsequent neurodegeneration and complete hippocampal atrophy within six weeks. The hyperactivation of SA increases IL-1β release, initiating an inflammatory feed-forward vicious cycle including NLRP3-inflammasome activation and Gasdermin D (GSDMD)-mediated neurotoxicity, which ultimately drives neurodegeneration. Results from protein expression and co-immunoprecipitation analyses of postmortem brains demonstrate that SA is hyperactivated in Alzheimer’s disease. Overall, our findings suggest that SKA2-regulated, hyperactive SA facilitates neuroinflammation and is linked to Alzheimer’s disease, providing new mechanistic insight into the biology of neuroinflammation.

Ordered assembly of the tau protein into filaments characterizes multiple neurodegenerative diseases, which are called tauopathies. We previously reported that by electron cryo-microscopy (cryo-EM), tau filament structures from Alzheimer’s disease (1,2), chronic traumatic encephalopathy (CTE) (3), Pick’s disease (4) and corticobasal degeneration (CBD) (5) are distinct. Here we show that the structures of tau filaments from typical and atypical progressive supranuclear palsy (PSP), the most common tauopathy after Alzheimer’s disease, define a previously unknown, three-layered fold. Moreover, the tau filament structures from globular glial tauopathy (GGT, Types I and II) are similar to those from PSP. The tau filament fold of argyrophilic grain disease (AGD) differs from the above and resembles the four-layered CBD fold. The majority of tau filaments from aging-related tau astrogliopathy (ARTAG) also have the AGD fold. Surprisingly, tau protofilament structures from inherited cases with mutations +3/+16 in intron 10 of MAPT, the microtubule-associated protein tau gene, are identical to those from AGD, suggesting that a relative overproduction of four-repeat tau can give rise to the AGD fold. Finally, tau filament structures from cases of familial British dementia (FBD) and familial Danish dementia (FDD) are the same as those from Alzheimer’s disease and primary age-related tauopathy (PART). These structures provide the basis for a classification of tauopathies that also allows identification of new entities, as we show here for a case diagnosed as PSP, but with abundant spherical 4R tau inclusions in limbic and other brain areas. The structures of the tau fold of this new disease (Limbic-predominant Neuronal inclusion body 4R Tauopathy, LNT) were intermediate between those of GGT and PSP.

Tauopathies are a subset of neurodegenerative diseases characterized by abnormal tau inclusions. Specifically, three-repeat tau and four-repeat tau in Alzheimer’s disease, three-repeat tau in Pick’s disease (PiD) and four-repeat tau in progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) form amyloid-like fibrous structures that accumulate in neurons and/or glial cells. Amplification and cell-to-cell transmission of abnormal tau based on the prion hypothesis are believed to explain the onset and progression of tauopathies. Recent studies support not only the self-propagation of abnormal tau, but also the presence of conformationally distinct tau aggregates, namely tau strains. Cryogenic electron microscopy analyses of patient-derived tau filaments have revealed disease-specific ordered tau structures. However, it remains unclear whether the ultrastructural and biochemical properties of tau strains are inherited during the amplification of abnormal tau in the brain. In this study, we investigated template-dependent amplification of tau aggregates using a cellular model of seeded aggregation. Tau strains extracted from human tauopathies caused strain-dependent accumulation of insoluble filamentous tau in SH-SY5Y cells. The seeding activity towards full-length four-repeat tau substrate was highest in CBD-tau seeds, followed by PSP-tau and Alzheimer’s disease (AD)-tau seeds, while AD-tau seeds showed higher seeding activity than PiD-tau seeds towards three-repeat tau substrate. Abnormal tau amplified in cells inherited the ultrastructural and biochemical properties of the original seeds. These results strongly suggest that the structural differences of patient-derived tau strains underlie the diversity of tauopathies, and that seeded aggregation and filament formation mimicking the pathogenesis of sporadic tauopathy can be reproduced in cultured cells. Our results indicate that the disease-specific conformation of tau aggregates determines the tau isoform substrate that is recruited for templated amplification, and also influences the prion-like seeding activity., Tarutani et al. show that pathogenic tau seeds extracted from the brains of patients with tauopathies induce disease-specific seeded tau aggregation and filament formation in cultured cells. The results indicate that template-dependent tau aggregation is key to the development of various types of tauopathy.

Fragile X‐associated tremor ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by a CGG trinucleotide expansion from 55 to 200 repeats in the non‐coding region of the fragile X mental retardation 1 (FMR1) gene (FMR1). Clinical features include cognitive decline, progressive tremor, and gait ataxia. Neuropathologically, FXTAS shows white matter changes, hippocampal and cerebellar involvement, and p62‐positive eosinophilic intranuclear inclusions in astrocytes and neurons. Here, we document the neuropathological findings from a subject who developed cognitive impairment but not tremor and was proved to have genetically confirmed FMR1 premutation. Microscopically, typical p62‐postive intranuclear inclusions were present in all the regions examined. Neocortical regions demonstrated gliosis of layer I and mild degree of neuronal loss and atrophy across the other layers. The molecular, Purkinje's cell, and granule cell layers of the cerebellar folia demonstrated mild gliosis, and cerebellar white matter was mildly affected. Aside from p62‐positive inclusions, the hippocampus was spared. Arteries in the deep white matter often showed changes consistent with moderate small vessel disease (SVD). Reactive gliosis and severe SVD were features of basal ganglia. Florid reactive astrocytosis was found in the white matter of all regions. Axonal loss and features of axonal damage were found in the white matter of the centrum semiovale. Microglial activation was widespread and evenly seen in both the white matter and grey matter, although the grey matter appeared more severely affected. Pathology associated with Alzheimer's disease was limited. Similarly, no abnormal accumulations of α‐synuclein were present. We postulate that age at death and disease duration may play a role in the extent of the pathological features associated with FXTAS. The present results suggest that immunohistochemical staining for p62 can help with the diagnosis of cases with atypical phenotype. In addition, it is likely that the cognitive impairment observed was a result of white matter changes.

Intracellular accumulation of abnormal proteins with conformational changes is the defining neuropathological feature of neurodegenerative diseases. The pathogenic proteins that accumulate in patients' brains adopt an amyloid-like fibrous structure and exhibit various ultrastructural features. The biochemical analysis of pathogenic proteins in sarkosyl-insoluble fractions extracted from patients’ brains also shows disease-specific features. Intriguingly, these ultrastructural and biochemical features are common within the same disease group. These differences among the pathogenic proteins extracted from patients’ brains have important implications for definitive diagnosis of the disease, and also suggest the existence of pathogenic protein strains that contribute to the heterogeneity of pathogenesis in neurodegenerative diseases. Recent experimental evidence has shown that prion-like propagation of these pathogenic proteins from host cells to recipient cells underlies the onset and progression of neurodegenerative diseases. The reproduction of the pathological features that characterize each disease in cellular and animal models of prion-like propagation also implies that the structural differences in the pathogenic proteins are inherited in a prion-like manner. In this review, we summarize the ultrastructural and biochemical features of pathogenic proteins extracted from the brains of patients with neurodegenerative diseases that accumulate abnormal forms of tau, α-synuclein, and TDP-43, and we discuss how these disease-specific properties are maintained in the brain, based on recent experimental insights.

We investigated the cerebral folate system in post-mortem brains and matched cerebrospinal fluid (CSF) samples from subjects with definite Alzheimer’s disease (AD) (n = 21) and neuropathologically normal brains (n = 21) using immunohistochemistry, Western blot and dot blot. In AD the CSF showed a significant decrease in 10-formyl tetrahydrofolate dehydrogenase (FDH), a critical folate binding protein and enzyme in the CSF, as well as in the main folate transporter, folate receptor alpha (FRα) and folate. In tissue, we found a switch in the pathway of folate supply to the cerebral cortex in AD compared to neurologically normal brains. FRα switched from entry through FDH-positive astrocytes in normal, to entry through glial fibrillary acidic protein (GFAP)-positive astrocytes in the AD cortex. Moreover, this switch correlated with an apparent change in metabolic direction to hypermethylation of neurons in AD. Our data suggest that the reduction in FDH in CSF prohibits FRα-folate entry via FDH-positive astrocytes and promotes entry through the GFAP pathway directly to neurons for hypermethylation. This data may explain some of the cognitive decline not attributable to the loss of neurons alone and presents a target for potential treatment.

Background: Early diagnosis of Alzheimer’s disease (AD) provides an opportunity for early intervention. Cognitive testing has proven to be a reliable way to identify individuals who may be at risk of AD. The Telephone Assessment for Cognitive Screening (TICS) is proficient in screening for cognitive impairment. However, its ability to identify those at risk of developing AD pathology is unknown. Objective: We aim to investigate associations between TICS scores, collected over a period of 13 years, and the cognitive status of participants at death. We also examine relationships between TICS scores and neuropathological indices of AD (CERAD score, Thal phase, and Braak stage). Methods: Between 2004 and 2017, participants from The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age underwent cognitive assessment using TICS. Scores from four time points were available for analysis. Cognitive impairment and AD pathology at death was evaluated in 101 participants. Results: TICS scores at time points 2, 3, and 4 were significantly lower in those cognitively impaired at death compared to those considered cognitively normal. There were significant negative correlations between TICS scores and CERAD score and Braak stage at time points 2 and 4. No correlations between Thal phase and TICS were found. Conclusion: Findings indicate that TICS could be used not only to screen for cognitive impairment, but also to identify individuals at risk of developing AD pathology, many years before any overt symptoms occur. Once identified, ‘at risk’ individuals could be targeted for early interventions which could attenuate the progression of the disease.

The sigma 1 receptor (S1R) is widely expressed in the CNS and is mainly located on the endoplasmic reticulum. The S1R is involved in the regulation of many neurotransmission systems and, indirectly, in neurodegenerative diseases. The S1R may therefore represent an interesting neuronal biomarker in neurodegenerative diseases such as Parkinson's (PD) or Alzheimer's diseases (AD). Here we present the characterisation of the S1R-specific 18F-labelled tracer 18F-IAM6067 in two animal models and in human brain tissue. Methods: Wistar rats were used for PET-CT imaging (60 min dynamic acquisition) and metabolite analysis (1, 2, 5, 10, 20, 60 min post-injection). To verify in vivo selectivity, haloperidol, BD1047 (S1R ligand), CM398 (S2R ligand) and SB206553 (5HT2B/C antagonist) were administrated for pre-saturation studies. Excitotoxic lesions induced by intra-striatal injection of AMPA were also imaged by 18F-IAM6067 PET-CT to test the sensitivity of the methods in a well-established model of neuronal loss. Tracer brain uptake was also verified by autoradiography in rats and in a mouse model of PD (intrastriatal 6-hydroxydopamine (6-OHDA) unilateral lesion). Finally, human cortical binding was investigated by autoradiography in three groups of subjects (control subjects with Braak ≤2, and AD patients, Braak >2 & ≤4 and Braak >4 stages). Results: We demonstrate that despite rapid peripheral metabolism of 18F-IAM6067, radiolabelled metabolites were hardly detected in brain samples. Brain uptake of 18F-IAM6067 showed differences in S1R anatomical distribution, namely from high to low uptake: pons-raphe, thalamus medio-dorsal, substantia nigra, hypothalamus, cerebellum, cortical areas and striatum. Pre-saturation studies showed 79-90% blockade of the binding in all areas of the brain indicated above except with the 5HT2B/C antagonist SB206553 and S2R ligand CM398 which induced no significant blockade, indicating good specificity of 18F-IAM6067 for S1Rs. No difference between ipsi- and contralateral sides of the brain in the mouse model of PD was detected. AMPA lesion induced a significant 69% decrease in 18F-IAM6067 uptake in the globus pallidus matching the neuronal loss as measured by NeuN, but only a trend to decrease (-16%) in the caudate putamen despite a significant 91% decrease in neuronal count. Moreover, no difference in the human cortical binding was shown between AD groups and controls. Conclusion: This work shows that 18F-IAM6067 is a specific and selective S1R radiotracer. The absence or small changes in S1R detected here in animal models and human tissue warrants further investigations and suggests that S1R might not be the anticipated ideal biomarker for neuronal loss in neurodegenerative diseases such as AD and PD.

0.ABSTRACTAmyloid beta (Aβ) is thought to play a critical role in the pathogenesis of Alzheimer’s disease (AD). Prion-like Aβ polymorphs, or “strains”, can have varying pathogenicity and may underlie the phenotypic heterogeneity of the disease. In order to develop effective AD therapies, it is critical to identify the strains of Aβ that might arise prior to the onset of clinical symptoms and understand how they may change with progressing disease. Down syndrome (DS), as the most common genetic cause of AD, presents promising opportunities to compare such features between early and advanced AD. In this work, we evaluate the neuropathology and Aβ strain profile in the post-mortem brain tissues of 210 DS, AD, and control individuals. We assayed the levels of various Aβ and tau species and used conformation-sensitive fluorescent probes to detect differences in Aβ strains among individuals and populations. We found that these cohorts have some common but also some distinct strains from one another, with the most heterogeneous populations of Aβ emerging in subjects with high levels of AD pathology. The emergence of distinct strains in DS at these later stages of disease suggests that the confluence of aging, pathology, and other DS-linked factors may favor conditions that generate strains that are unique from sAD.

Perinatal light exposure predisposes towards health and behaviour in adulthood. Season of birth is associated with psychiatric, allergic, cardiovascular and metabolic problems. It has been proposed that early-life environmental light disrupts the development of biological rhythms which, in turn, influence later-life health. However, the mechanisms linking perinatal seasonal light to later-life biological rhythm and health in humans are unknown. In this study, we investigated the association between season of birth and epigenome-wide DNA methylation of two postmortem human brain regions (16 hypothalamus, 14 temporal cortex). We did not find statistically significant differences at the whole epigenome level, either because we lacked statistical power or that no association exists. However, when we examined 24 CpG sites that had the highest significance or differential methylation, we identified regions which may be associated with circadian rhythm entrainment, cholinergic neurotransmission and neural development. Amongst methylation of the core clock genes, we identified that hypothalamus Neuronal PAS Domain Protein 2 (NPAS2) gene has hypermethylated regions in long photoperiod-born individuals. In addition, we found nominal associations between season of birth and genes linked to chronotype and narcolepsy. Season of birth-related brain DNA methylation profile was different than a previously reported blood methylation profile, suggesting a tissue-specific mechanism of perinatal light programming. Overall, we are the first to analyse the relationship between season of birth and human brain DNA methylation. Further studies with larger sample sizes are required to confirm an imprinting effect of perinatal light on the circadian clock.

Background: The APOE ɛ4 allele is the strongest known genetic risk factor for sporadic Alzheimer’s disease (AD). The neighboring TOMM40 gene has also been implicated in AD due to its close proximity to APOE. Objective: Here we tested whether methylation of the TOMM40-APOE locus may influence ApoE protein levels and AD pathology. Methods: DNA methylation levels across the TOMM40-APOE locus and ApoE levels were measured in superior frontal gyrus tissues of 62 human brains genotyped for APOE and scored for AD neuropathology. Results: Methylation levels within the TOMM40 CpG island in the promoter or APOE CpG island in Exon 4 did not differ between APOE ɛ4 carriers versus non-carriers. However, APOE ɛ4 carriers had significantly higher methylation the APOE promoter compared with non-carriers. Although DNA methylation at TOMM40, APOE promoter region, or APOE did not differ between AD pathological groups, there was a negative association between TOMM40 methylation and CERAD scores. ApoE protein concentrations did not significantly different between APOE ɛ4 carriers and non-carriers, or between AD pathological groups. Finally, there was no correlation between ApoE protein concentrations and DNA methylation levels. Conclusion: APOE gene methylation may not be affected by genotype, relate to AD pathology or ApoE protein levels in the superior frontal gyrus, though, DNA methylation at the ApoE promoter differed between genotype. DNA methylation at TOMM40 associated with amyloid-β plaques and longitudinal fluid intelligence. In sum, these results suggest a complicated regulation of the TOMM40-APOE locus in the brain in controlling ApoE protein levels and AD neuropathology.

The observation of neurofibrillary tangles (NFTs) without associated amyloid-beta (Aβ) in the brains of cognitively normal and cognitively impaired elderly individuals has, for many years, been a source of discussion and controversy. The term "primary age-related tauopathy" (PART) was introduced in 2014 and consensus guidelines for the condition were published [1]. The clinical manifestations of PART have been described (see [2] for review). A recent molecular imaging study suggested that mesial temporal tau load is associated with a decline in cognitive performance in those with no Aβ pathology [3].

Blockade of PD-1/PD-L1 interactions is proving an exciting, durable therapeutic modality in a range of cancers whereby T cells are released from checkpoint inhibition to revive their inherent anti-tumour activity. Here we have studied various ways to model ex vivo T cell function in order to compare the impact of the clinically utilised anti-PD-1 antibody, pembrolizumab (Keytruda) on the activation of human T cells: focussing on the release of pro-inflammatory IFNγ and anti-inflammatory IL-10 to assess functionality. Firstly, we investigated the actions of pembrolizumab in an acute model of T-cell activation with either immature or mature allogeneic dendritic cells (DCs); pembrolizumab enhanced IFNγ and IL-10 release from purified CD4+ T-cells in the majority of donors with a bias towards pro-inflammatory cytokine release. Next, we modelled the impact of pembrolizumab in settings of more chronic T-cell activation. In a 7-day antigen-specific response to EBV peptides, the presence of pembrolizumab resulted in a relatively modest increase in both IFNγ and IL-10 release. Where pembrolizumab was assessed against long-term stimulated CD4+ cells that had up-regulated the exhaustion markers TIM-3 and PD-1, there was a highly effective enhancement of the otherwise exhausted response to allogeneic DCs with respect to IFNγ production. By contrast, the restoration of IL-10 production was considerably more limited. Finally, to assess a direct clinical relevance we investigated the consequence of PD-1/PD-L1 blockade in the disease setting of dissociated cells from lung and colon carcinomas responding to allogeneic DCs: here, pembrolizumab once more enhanced IFNγ production from the majority of tumour preparations whereas, again, the increase in IL-10 release was modest at best. In conclusion, we have shown that the contribution of PD-1—revealed by using a canonical blocking antibody to interrupt its interaction with PD-L1—to the production of an exemplar pro- and anti-inflammatory cytokine, respectively, depends in magnitude and ratio on the particular stimulation setting and activation status of the target T cell. We have identified a number of in vitro assays with response profiles that mimic features of dissociated cell populations from primary tumours thereby indicating these represent disease-relevant functional assays for the screening of immune checkpoint inhibitors in current and future development. Such in vitro assays may also support patient stratification of those likely to respond to immuno-oncology therapies in the wider population.

Objectives: Early diagnosis of Alzheimer's disease (AD) is essential for early interventions. Symptoms of depression could represent a prodromal stage of AD. Very early mood alterations may help stratify those at highest risk of late-life AD. We aim to investigate associations between baseline/longitudinal scores for depression, presence of cognitive impairment and/or AD pathology at death.Methods/Design: Between 1991 and 2015, participants from The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age underwent 10 waves of assessment using the Geriatric Depression Scale (GDS). AD pathology at death was evaluated in 106 eligible cases. Analyses aimed to examine associations between GDS scores, cognitive status and AD pathology (as measured by Braak stage, Thal phase and CERAD).Results: Baseline GDS scores were significantly higher for those cognitively impaired at death than those cognitively normal. Significantly higher baseline GDS scores were found for those with greater CERAD scores than those with lower CERAD scores. Similarly, significantly higher baseline GDS scores were found for those with a greater Braak stage than those with lower tau burden. These correlations remained after controlling for age at death, education and APOE ε4, but were less robust. Mean longitudinal GDS scores associated with cognition but not pathology.Conclusions: GDS scores collected approximately 20 years before death were associated with cognitive status and AD pathology at death. We postulate that early AD-related pathological change produces raised GDS scores due to an overlapping neural basis with depression, and that this may be considered as an early diagnostic marker for AD. This article is protected by copyright. All rights reserved.

While many studies have examined the associations between APOE genotype and mortality, findings have often been conflicting and it remains unclear whether APOE genotype affects longevity. Using selected individuals from the Manchester arm of the Brains for Dementia Research programme and University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age, we investigated relationships between APOE genotype and age at death in both cognitively normal and cognitively impaired individuals. Results indicated that carrying the APOE ɛ4 allele led to a reduced chance in an individual reaching 80+ years and remaining cognitively healthy. Conversely, APOE ɛ2 carriers tended to live longer and remain cognitively normal. These findings add to the evidence that APOE genotype influences longevity, especially in cognitively impaired individuals who carry the APOE ɛ4 allele.

Background:An early symptom of Alzheimer’s disease (AD) is a disturbance of the circadian rhythm that is associated with disrupted sleep/wake cycles.Objective:To investigate if BMAL1, a key gene that drives the circadian cycle, is epigenetically regulated in brains in relation to longitudinal changes in cognition, sleep quality, and AD neuropathology.Methods:Frontal cortex tissues were acquired from the Manchester Brain Bank (N = 96). DNA methylation at six CpG sites at the promoter of BMAL1, determined using bisulfite pyrosequencing, was tested for associations with Braak stage, CERAD score, and Thal phase, longitudinal changes in cognition, sleep measurements, and cross-section measures of depressive symptoms (BDI score).Results:Methylation across all the CpGs strongly correlated with each other. We found increased CpG2 methylation with higher Braak (t(92) = 2.47, p = 0.015) and CERAD (t(94) = 2.04, p = 0.044) stages. No significance was found between longitudinal fluid intelligence, processing speed, and memory tests, but methylation at CpG1 (r = 0.20, p = 0.05) and CpG4 (r = 0.20, p = 0.05) positively correlated with vocabulary. CpG2 positively correlated with cross-sectional fluid intelligence (r = 0.20 p = 0.05) and vocabulary (r = 0.22 p = 0.03). Though longitudinal analysis revealed no significance between sleep duration, midsleep, and efficiency for any of the CpG sites, CpG3 (B = 0.03, 95% CI = 0.00/0.06, p = 0.03) and CpG5 (B = 0.04, 95% CI = 0.01,0.07, p = 0.01) significantly correlated with night wake. CpG4 correlated with depressive symptoms (B = –0.27, 95% CI=0.49/–0.05, p = 0.02).Conclusion:Methylation of BMAL1 associated with tau pathology, changes in cognitive measures, a measure of sleep and depressive symptoms, suggesting an involvement of the circadian cycle.

BACKGROUND: The pathological features of Alzheimer's disease (AD) are well described but little is known as to how both neurodegeneration and vascular changes might interact in causing cognitive impairment.OBJECTIVE: The present study aims to investigate relationships between vascular and AD pathology in cognitively healthy and cognitively impaired individuals with a particular emphasis on those at intermediate Braak tau stages.METHODS: We investigated the interplay between Braak tau stage and measures of vascular pathology as described by the vascular cognitive impairment neuropathology guidelines (VCING) in 185 brains from the Brains for Dementia Research programme and The University of Manchester Longitudinal Study of Cognition in Healthy Old Age. VCING asserts that at least one large (>10 mm) infarct, moderate/severe occipital leptomeningeal cerebral amyloid angiopathy, and moderate/severe arteriosclerosis in occipital white matter accurately predicts the contribution of cerebrovascular pathology to cognitive impairment.RESULTS: We found that the extent of arteriosclerosis in the occipital white matter did not differ between cognitive groups at intermediate (III-IV) Braak stages whereas moderate/severe leptomeningeal occipital cerebral amyloid angiopathy was greater in cognitively impaired than normal individuals at Braak stage III-IV. This finding remained significant after controlling for effects of age, sex, CERAD score, Thal phase, presence/severity of primary age-related tauopathy, presence/severity of limbic-predominant age-related TDP43 encephalopathy and small vessel disease in basal ganglia.CONCLUSION: Interventions targeting cerebral amyloid angiopathy may contribute to delay the onset of cognitive impairment in individuals with intermediate Alzheimer's type pathology.

While many studies have examined the associations between APOE genotype and mortality, findings have oftenbeen conflicting and it remains unclear whether APOE genotype affects longevity. Using selected individuals from theManchester arm of the Brains for Dementia Research programme and University of Manchester Longitudinal Study ofCognition in Normal Healthy Old Age, we investigated relationships between APOE genotype and age at death in bothcognitively normal and cognitively impaired individuals. Results indicated that carrying the APOE 4 allele led to a reducedchance in an individual reaching 80+ years and remaining cognitively healthy. Conversely, APOE 2 carriers tended to livelonger and remain cognitively normal. These findings add to the evidence that APOE genotype influences longevity, especiallyin cognitively impaired individuals who carry the APOE 4 allele.

A failure of protein degradation may underpin Lewy body disease (LBD) where α-synuclein is assimilated into the pathognomic Lewy bodies and Lewy neurites. We investigated histological alterations in lysosomes and autophagosomes in the substantia nigra (SN) and cingulate gyrus (CG) in 34 patients with LBD employing antibodies against phosphorylated α-synuclein and lysosomal (lysosomal associated membrane proteins 1 and 2 (LAMP-1 and LAMP-2), cathepsin D (CTSD)) and autophagosomal (microtubule-associated protein light chain 3α (LC3A)) proteins. Immunostained sections were qualitatively and semi-quantitatively assessed for the appearance, distribution and intensity of staining. Four LBD patients had mutations in GBA1. There was significantly less LAMP-1, LAMP-2 and CTSD immunostaining in neurons of the SN in LBD cases compared to control cases and marginally less LAMP-1 in patients with GBA1 mutations compared to those without. Loss of LAMP-1 and CTSD immunoreactivity correlated with cell loss from the SN. There were no changes in LC3A immunoreactivity in the SN, nor any major changes in the CG, or glial cell activity in the SN and CG, for any of the markers. A proportion of amyloid plaques in both the LBD and control cases was immunoreactive for LAMP-1 and LAMP-2, but not CTSD or LC3A proteins. These immunohisochemical features were seen in glial cells, which were negative for amyloid-β. Alterations in lysosomal structure or function, but not macroautophagy, may underpin the pathogenesis of LBD.

International audience; Chronic low-grade inflammation during aging (inflammaging) is associated with cognitive decline and neurodegeneration; however, the mechanisms underlying inflammaging are unclear. We studied a population (n = 361) of healthy young and old adults from the MyoAge cohort. Peripheral levels of C-X-C motif chemokine ligand 10 (CXCL10) was found to be higher in older adults, compared with young, and negatively associated with working memory performance. This coincided with an age-related reduction in blood DNA methylation at specific CpGs within the CXCL10 gene promoter. In vitro analysis supported the role of DNA methylation in regulating CXCL10 transcription. A polymorphism (rs56061981) that altered methylation at one of these CpG sites further associated with working memory performance in 2 independent aging cohorts. Studying prefrontal cortex samples, we found higher CXCL10 protein levels in those with Alzheimer's disease, compared with aged controls. These findings support the association of peripheral inflammation, as demonstrated by CXCL10, in aging and cognitive decline. We reveal age-related epigenetic and genetic factors which contribute to the dysregulation of CXCL10.

In the present study we have characterised and compared individuals whose brains were donated as part of The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age (UoM) with those donated through the Manchester arm of the UK Brains for Dementia Research (BDR) programme. The aim of this study was to investigate how differences in study recruitment may affect final pathological composition of cohort studies.UoM cohort was established as a longitudinal study of ageing and cognition whereas the BDR programme was established, prima facie, to collect brains from both demented and non-demented individuals for the purpose of building a tissue research resource. Consequently, the differences in recruitment patterns generated differences in demographic, clinical and neuropathological characteristics. There was a higher proportion of recruits with dementia (mostly Alzheimer’s disease (AD)) within the BDR cohort than in UoM cohort. In pathological terms, the BDR cohort was more ‘polarised’, being more composed of demented cases with high Braak pathology scores and non-demented cases with low Braak scores, and fewer non-AD pathology cases, than UoM cohort. In both cohorts, cerebral amyloid angiopathy (CAA) tended to be greater in demented than non-demented individuals. Such observations partly reflect the recruitment of demented and non-demented individuals into the BDR cohort, and also that insufficient study time may have elapsed for disease onset and development in non-demented individuals to take place. Conversely, in UoM cohort, where there had been nearly 30 years of study time, a broader spread of AD-type pathological changes had ‘naturally’ evolved in the brains of both demented and non-demented participants.

Background The glucocorticoid receptor (NR3C1, GR) is frequently downregulated in breast tumors, and evidence suggests it acts as a tumor suppressor in estrogen receptor-positive (ER+) breast cancer. We previously found that methylation of the GR promoter CpG island represses gene expression and occurs in ER+ breast tumors. In this study, the prognostic and predictive value of GR methylation was examined in ER+ patients from the CCTG MA.12 clinical trial of tamoxifen versus placebo in women with early breast cancer. Methods We developed a targeted multiplex bisulfite next-generation sequencing assay to detect methylation at multiple GR promoter regions in DNA from formalin-fixed paraffin-embedded (FFPE) samples. Following validation in a small cohort of breast tumors, ER+ FFPE tumor samples from MA.12 (n = 208) were tested. Survival analyses evaluated the impact of GR promoter methylation on patient overall survival (OS) and disease-free survival (DFS). Results An analysis of TCGA data found that GR methylation is prevalent in ER+ tumors and is associated with decreased gene expression and analysis of public microarray data (KM Plotter) linked decreased GR expression to a poor outcome. In MA.12, two GR promoter regions (U and C) each had prognostic value, but with opposite effects on the outcome. U methylation was associated with poor OS (HR = 1.79, P = 0.041) whereas C methylation was associated with better OS (HR = 0.40, P = 0.040) and DFS (HR = 0.49, P = 0.037). The classification of patients based on the methylation status of the two regions was prognostic for OS (P = 0.006) and DFS (P = 0.041) and revealed a group of patients (U methylated, C unmethylated) with very poor outcomes. Placebo-treated patients in this high-risk group had worse OS (HR = 2.86, P = 0.002) and DFS (HR = 2.09, P = 0.014) compared to the rest of the cohort. Conclusion Region-specific GR promoter methylation was an independent prognostic marker for patient survival and identified a subset of patients with poor prognosis, particularly without tamoxifen treatment. These findings provide a foundation for future studies into GR methylation as a promising prognostic biomarker in ER+ breast cancer.

Recent epigenome-wide association studies in Alzheimer's disease have highlighted consistent robust neuropathology-associated DNA hypermethylation of the ankyrin 1 (ANK1) gene in the cortex. The extent to which altered ANK1 DNA methylation is also associated with other neurodegenerative diseases is not currently known. In the present study, we used bisulfite pyrosequencing to quantify DNA methylation across 8 CpG sites within a 118 bp region of the ANK1 gene across multiple brain regions in Alzheimer's disease, Vascular dementia, Dementia with Lewy bodies, Huntington's disease, and Parkinson's disease. We demonstrate disease-associated ANK1 hypermethylation in the entorhinal cortex in Alzheimer's disease, Huntington's disease, and Parkinson's disease, whereas in donors with Vascular dementia and Dementia with Lewy bodies, we observed elevated ANK1 DNA methylation only in individuals with coexisting Alzheimer's disease pathology. We did not observe any disease-associated differential ANK1 DNA methylation in the striatum in Huntington's disease or the substantia nigra in Parkinson's disease. Our data suggest that ANK1 is characterized by region and disease-specific differential DNA methylation in multiple neurodegenerative diseases.

Intracellular filamentous tau pathology is the defining feature of tauopathies, which form a subset of neurodegenerative diseases. We have analyzed pathological tau in Alzheimer’s disease, and in frontotemporal lobar degeneration associated with tauopathy to include cases with Pick bodies, corticobasal degeneration, progressive supranuclear palsy, and ones due to intronic mutations in MAPT. We found that the C-terminal band pattern of the pathological tau species is distinct for each disease. Immunoblot analysis of trypsin-resistant tau indicated that the different band patterns of the 7–18 kDa fragments in these diseases likely reflect different conformations of tau molecular species. Protein sequence and mass spectrometric analyses revealed the carboxyl-terminal region (residues 243–406) of tau comprises the protease-resistant core units of the tau aggregates, and the sequence lengths and precise regions involved are different among the diseases. These unique assembled tau cores may be used to classify and diagnose disease strains. Based on these results, we propose a new clinicopathological classification of tauopathies based on the biochemical properties of tau. Electronic supplementary material The online version of this article (doi:10.1007/s00401-015-1503-3) contains supplementary material, which is available to authorized users.

ObjectivesHead injury with loss of consciousness (HI-LOC) is a common occurrence. Some studies have linked such injuries with an increased risk of Alzheimer’s disease (AD). However, recent large clinicopathologic studies have failed to find a clear relationship between HI-LOC and the pathological changes associated with AD. The present study aims to further investigate the relationship between HI-LOC and AD pathology in the elderly.Methods/DesignHistory of HI-LOC in participants in The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age was ascertained. The donated brains of 110 of these individuals were assessed for AD pathology using consensus guidelines. Analyses aimed to elucidate relationships between HI-LOC and AD pathology.ResultsNo associations were found between incidence of HI-LOC and regional AD pathology or any of the three established measures of the neuropathology associated with AD: CERAD score, Thal phase or Braak stage.ConclusionsSingle incidences of HI-LOC may not be sufficient to cause the pathology associated with late-stage AD. Other routes of damage, such as diffuse axonal injury or Lewy body pathology, may play a greater role in causing cognitive impairment associated with head injury.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is essential for neurogenesis and has been implicated in Alzheimer's disease (AD). However, few studies have investigated together the epigenetic, transcriptional, and translational regulation of this peptide in the brain in relation to AD.OBJECTIVE: To investigate mechanisms underlying how BDNF is possibly dysregulated in the brain in relation to aging and AD neuropathology.METHODS: Prefrontal cortex tissues were acquired from the Manchester Brain Bank (N = 67). BDNF exon I, and exon IV-containing transcripts and total long 3' transcript gene expression were determined by quantitative PCR and bisulfite pyrosequencing was used to quantify DNA methylation within promoters I and IV. Protein concentrations were quantified via ELISA.RESULTS: BDNF exon IV and total long 3' isoform gene expression levels negatively associated with donor's age at death (IV: r = -0.291, p = 0.020; total: r = -0.354, p = 0.004). Expression of BDNF exon I- containing isoform was significantly higher in Met-carriers of the rs6265 variant, compared to Val-homozygotes, when accounting for donor ages (F = 6.455, p = 0.014). BDNF total long 3' transcript expression was significantly lower in those with early AD neuropathology, compared to those without any neuropathology (p = 0.021). There were no associations between BDNF promoter I and IV methylation or protein levels with ages, rs6265 genotype or AD neuropathology status.CONCLUSION: Prefrontal cortex BDNF gene expression is associated with aging, rs6265 carrier status, and AD neuropathology in a variant-specific manner that seems to be independent of DNA methylation influences.

While post mortem studies have identified the major cell types and functional systems affected in Alzheimer’s disease (AD) the initial sites and molecular characteristics of pathology are still unclear. Because individuals with Down syndrome (DS) (trisomy 21) develop the full pathological changes of AD in a predictable way by the time they reach middle to late age, a study of the brains of such persons at different ages makes an ideal ‘model system’ in which the sites of earliest onset of pathology can be detected and the subsequent progression of changes be monitored. In the present study we have examined the brains of 56 individuals with DS ranging from new-born to 76 years for the presence of amyloid and tau pathology in key cortical and subcortical regions. Amyloid pathology was found to commence in the late teens to twenties as a deposition of diffuse plaques initially within the temporal neocortex, quickly involving other neocortical regions but only reaching subcortical regions and cerebellum by the late forties. Cerebral amyloid angiopathy did not regularly commence until after 45–50 years of age. Tau pathology usually commenced after 35 years of age, initially involving not only entorhinal areas and hippocampus but also subcortical regions such as locus caeruleus (LC) and dorsal raphe nucleus (DRN). Later, tau pathology spread throughout the neocortex reaching occipital lobes in most instances by mid-50 years of age. Such a pattern of spread is consistent with that seen in typical AD. We found no evidence that tau pathology might commence within the brain in DS before amyloid deposition had occurred, but there was limited data that suggests tau pathology in LC or DRN might predate that in entorhinal areas and hippocampus or at least be coincident.

Huntington's disease (HD) is a devastating, progressive neurodegenerative disease with a distinct phenotype characterized by chorea and dystonia, incoordination, cognitive decline and behavioral difficulties. The precise mechanisms of HD progression are poorly understood; however, it is known that there is an expansion of the trinucleotide cytosine-adenine-guanine (CAG) repeat in the Huntingtin gene. Herein DI/LC-MS/MS was used to accurately identify and quantify 185 metabolites in post mortem frontal lobe and striatum from HD patients and healthy control cases. The findings link changes in energy metabolism and phospholipid metabolism to HD pathology and also demonstrate significant reductions in neurotransmitters. Further investigation into the oxidation of fatty acids and phospholipid metabolism in pre-clinical models of HD are clearly warranted for the identification of potential therapies. Additionally, panels of 5 metabolite biomarkers were identified in both the frontal lobe (AUC = 0.962 (95% CI: 0.85–1.00) and striatum (AUC = 0.988 (95% CI: 0.899–1.00). This could have clinical utility in more accessible biomatrices such as blood serum for the early detection of those entering the prodromal phase of the disease, when treatment is believed to be most effective. Further evaluation of these biomarker panels in human cohorts is justified to determine their clinical efficacy.

Introduction Due to rising service pressures there is a need for innovation to optimise efficiency on acute medical and gastroenterology wards. Using smartphone applications to achieve this is an attractive proposition, but the utility of such technologies in clinical practice is unclear. Here, we report the experience of multidisciplinary staff after a pilot of a smartphone application at our hospital. Methods Two acute medical wards (including a 24 bed gastroenterology ward), were selected for a two-week pilot trial of a smartphone application, Listrunner (Desma Health, Canada), during October 2017. Multidisciplinary team members including; doctors, pharmacists, and nurses, were given access to Listrunner via dedicated secure mobile devices. During daily consultant ward rounds and throughout the working day, all tasks were uploaded onto Listrunner. A Control Centre lead reviewed all uploaded tasks, identified non-medical tasks and either completed these or reassigned them to more appropriate team members. At the end of the pilot, staff provided feedback on their experience via a structured questionnaire. Results During the pilot, whilst a total of 1080 tasks were uploaded onto Listrunner, 20% of these were non-medical tasks managed by the Control Centre. The most common tasks managed by Control Centre were chasing specialty reviews (42%) and chasing investigations (33%). At the end of the pilot, staff from both wards (n=19; Junior Doctors n=9, Nurses n=4, Consultants n=2, Pharmacists n=2 and Occupational Therapists n=2), completed questionnaires. Most doctors (73%) found Listrunner easy to use and 56% of juniors felt that it improved the relevance of their work by reassigning non-medical tasks. Overall, 42% rated Listrunner as ‘useful’, whereas 21% did not find it useful and 56% felt it improved communication between team members. When asked how Listrunner affected the conduct of ward work, the most popular responses selected were; ‘it improved patient flow/discharges’ (n=8), ‘it speeded up allocation of tasks’ (n=7) and ‘it prolonged the ward round’ (n=6). Whilst 12/19 (63%) felt it would be worth adopting Listrunner, 8/19 (42%) expressed some reservations about using smartphones in front of patients. The main barrier to adopting this technology more widely (according to 58%) would be the staffing levels and related costs required to replicate the pilot experience. Conclusions Our data suggest that a large number of tasks currently performed by doctors on acute wards are non-medical tasks. Smartphone technology appears to have potential to improve efficiency and streamline clinical activities, and our early experience may help inform future adoption and further development of this technology.

A failure of protein degradation may underpin Lewy body disease (LBD) where α-synuclein is assimilated into the pathognomic Lewy bodies and Lewy neurites. We investigated histological alterations in lysosomes and autophagosomes in the substantia nigra (SN) and cingulate gyrus (CG) in 34 patients with LBD employing antibodies against phosphorylated α-synuclein and lysosomal (lysosomal associated membrane proteins 1 and 2 (LAMP-1 and LAMP-2), cathepsin D (CTSD)) and autophagosomal (microtubule-associated protein light chain 3α (LC3A)) proteins. Immunostained sections were qualitatively and semi-quantitatively assessed for the appearance, distribution and intensity of staining. Four LBD patients had mutations in GBA1. There was significantly less LAMP-1, LAMP-2 and CTSD immunostaining in neurons of the SN in LBD cases compared to control cases and marginally less LAMP-1 in patients with GBA1 mutations compared to those without. Loss of LAMP-1 and CTSD immunoreactivity correlated with cell loss from the SN. There were no changes in LC3A immunoreactivity in the SN, nor any major changes in the CG, or glial cell activity in the SN and CG, for any of the markers. A proportion of amyloid plaques in both the LBD and control cases was immunoreactive for LAMP-1 and LAMP-2, but not CTSD or LC3A proteins. These immunohisochemical features were seen in glial cells, which were negative for amyloid-β. Alterations in lysosomal structure or function, but not macroautophagy, may underpin the pathogenesis of LBD.

AIMS: Frontotemporal lobar degeneration (FTLD) and Motor Neuron Disease are linked by the possession of a hexanucleotide repeat expansion in C9ORF72, and both show neuronal cytoplasmic inclusions within cerebellar and hippocampal neurones which are TDP-43 negative but immunoreactive for p62 and dipeptide repeat proteins (DPR), these being generated by a non-ATG RAN translation of the expanded region of the gene. METHODS: Twenty two cases of FTLD from Newcastle were analyzed for an expansion in C9ORF72 by repeat primed PCR and Southern blot. Detailed case note analysis was performed, and blinded retrospective clinical impressions were achieved by review of clinical histories. Sections from all major brain regions were immunostained for TDP-43, p62 and DPR. The extent of TDP-43 and DPR pathology in expansion bearers was compared to that in 13 other previously identified cases from the Manchester Brain Bank with established disease. RESULTS: Three Newcastle patients bearing an expansion in C9ORF72 were identified. These 3 patients died prematurely, two from bronchopneumonia within 10 months and 3 years of onset, and one from myocardial infarction 3 years after onset. In all three, DPR were plentiful throughout all cerebral cortical regions, hippocampus and cerebellum, but TDP-43 pathological changes were sparse. The severity of DPR pathological changes in these 3 patients was similar to that in the Manchester series, though the extent of TDP-43 pathology was significantly less. CONCLUSION: Widespread accumulation of DPR within nerve cells may occur much earlier than that of TDP-43 in patients with FTLD bearing expansion in C9ORF72.

The neuropathological changes responsible for cognitive impairment and dementia remain incompletely understood. Longitudinal studies with a brain donation end point allow the opportunity to examine relationships between cognitive status and neuropathology. We report on the first 97 participants coming to autopsy with sufficient clinical information from The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age. This study began in 1983 and recruited 6,542 healthy individuals between 1983 and 1994, 312 of whom consented to brain donation. Alzheimer-type pathology was common throughout the cohort and generally correlated well with cognitive status. However, there was some overlap between cognitive status and measures of Alzheimer pathology with 26% of cognitively intact participants reaching either CERAD B or C, 11% reaching Thal phase 4 or 5, and 29% reaching Braak stage III- VI. Cerebral amyloid angiopathy(CAA), α-synuclein, and TDP-43 pathology was less common, but when present correlated well with cognitive status. Possession of APOEɛ4 allele(s) was associated with more severe Alzheimer-type and CAA pathology and earlier death, whereas possession of APOEɛ2 allele(s) had no effect on pathology but was more common in cognitively intact individuals. The University of Manchester Longitudinal Study of Cognition in Normal Healthy Old Age cohort is pathologically representative when compared with similar studies. Cognitive impairment in life correlates strongly with all pathologies examined and the APOE status of an individual can affect pathology severity and longevity.

In this study, we have compared the severity of amyloid plaque formation and cerebral amyloid angiopathy (CAA), and the subtype pattern of CAA pathology itself, between APP genetic causes of AD (APPdup, APP mutations), older individuals with Down syndrome (DS) showing the pathology of Alzheimer’s disease (AD) and individuals with sporadic (early and late onset) AD (sEOAD and sLOAD, respectively). The aim of this was to elucidate important group differences and to provide mechanistic insights related to clinical and neuropathological phenotypes. Since lipid and cholesterol metabolism is implicated in AD as well as vascular disease, we additionally aimed to explore the role of APOE genotype in CAA severity and subtypes. Plaque formation was greater in DS and missense APP mutations than in APPdup, sEOAD and sLOAD cases. Conversely, CAA was more severe in APPdup and missense APP mutations, and in DS, compared to sEOAD and sLOAD. When stratified by CAA subtype from 1 to 4, there were no differences in plaque scores between the groups, though in patients with APPdup, APP mutations and sEOAD, types 2 and 3 CAA were more common than type 1. Conversely, in DS, sLOAD and controls, type 1 CAA was more common than types 2 and 3. APOE ε4 allele frequency was greater in sEOAD and sLOAD compared to APPdup, missense APP mutations, DS and controls, and varied between each of the CAA phenotypes with APOE ε4 homozygosity being more commonly associated with type 3 CAA than types 1 and 2 CAA in sLOAD and sEOAD. The differing patterns in CAA within individuals of each group could be a reflection of variations in the efficiency of perivascular drainage, this being less effective in types 2 and 3 CAA leading to a greater burden of CAA in parenchymal arteries and capillaries. Alternatively, as suggested by immunostaining using carboxy-terminal specific antibodies, it may relate to the relative tissue burdens of the two major forms of Aβ, with higher levels of Aβ40 promoting a more ‘aggressive’ form of CAA, and higher levels of Aβ42(3) favouring a greater plaque burden. Possession of APOE ε4 allele, especially ε4 homozygosity, favours development of CAA generally, and as type 3 particularly, in sEOAD and sLOAD. Electronic supplementary material The online version of this article (10.1007/s00401-018-1866-3) contains supplementary material, which is available to authorized users.