Complement factor C3 is the central component of the complement system and a key inflammatory protein activated in Alzheimer's disease (AD). Previous studies demonstrated that inhibition of C3 by ...overexpression of soluble complement receptor-related protein y in an AD mouse model led to reduced microgliosis, increased amyloid beta (Abeta) plaque burden, and neurodegeneration. To further address the role of C3 in AD pathology, we generated a complement C3-deficient amyloid precursor protein (APP) transgenic AD mouse model (APP;C3(-/-)). Brains were analyzed at 8, 12, and 17 months of age by immunohistochemical and biochemical methods and compared with age-matched APP transgenic mice. At younger ages (8-12 months), no significant neuropathological differences were observed between the two transgenic lines. In contrast, at 17 months of age, APP;C3(-/-) mice showed significant changes of up to twofold increased total Abeta and fibrillar amyloid plaque burden in midfrontal cortex and hippocampus, which correlated with (1) significantly increased Tris-buffered saline (TBS)-insoluble Abeta(42) levels and reduced TBS-soluble Abeta(42) and Abeta(40) levels in brain homogenates, (2) a trend for increased Abeta levels in the plasma, (3) a significant loss of neuronal-specific nuclear protein-positive neurons in the hippocampus, and (4) differential activation of microglia toward a more alternative phenotype (e.g., significantly increased CD45-positive microglia, increased brain levels of interleukins 4 and 10, and reduced levels of CD68, F4/80, inducible nitric oxide synthase, and tumor necrosis factor). Our results suggest a beneficial role for complement C3 in plaque clearance and neuronal health as well as in modulation of the microglia phenotype.
Angiogenesis is a common finding in chronic inflammatory diseases; however, its role in multiple sclerosis (MS) is unclear. Central nervous system lesions from both MS and experimental autoimmune ...encephalomyelitis (EAE), the animal model of MS, contain T cells, macrophages and activated glia, which can produce pro-angiogenic factors. Previous EAE studies have demonstrated an increase in blood vessels, but differences between the different phases of disease have not been reported. Therefore we examined angiogenic promoting factors in MS and EAE lesions to determine if there were changes in blood vessel density at different stages of EAE.
In this series of experiments we used a combination of vascular casting, VEGF ELISA and immunohistochemistry to examine angiogenesis in experimental autoimmune encephalomyelitis (EAE). Using immunohistochemistry we also examined chronic active MS lesions for angiogenic factors.
Vascular casting and histological examination of the spinal cord and brain of rats with EAE demonstrated that the density of patent blood vessels increased in the lumbar spinal cord during the relapse phase of the disease (p < 0.05). We found an increased expression of VEGF by inflammatory cells and a decrease in the recently described angiogenesis inhibitor meteorin. Examination of chronic active human MS tissues demonstrated glial expression of VEGF and glial and blood vessel expression of the pro-angiogenic receptor VEGFR2. There was a decreased expression of VEGFR1 in the lesions compared to normal white matter.
These findings reveal that angiogenesis is intimately involved in the progression of EAE and may have a role in MS.
Spinal muscular atrophy (SMA) is a monogenic disorder caused by loss of function mutations in the survival motor neuron 1 gene, which results in a broad range of disease severity, from neonatal to ...adult onset. There is currently a concerted effort to define the natural history of the disease and develop outcome measures that accurately capture its complexity. As several therapeutic strategies are currently under investigation and both the FDA and EMA have recently approved the first medical treatment for SMA, there is a critical need to identify the right association of responsive outcome measures and biomarkers for individual patient follow-up. As an approved treatment becomes available, untreated patients will soon become rare, further intensifying the need for a rapid, prospective and longitudinal study of the natural history of SMA Type 2 and 3. Here we present the baseline assessments of 81 patients aged 2 to 30 years of which 19 are non-sitter SMA Type 2, 34 are sitter SMA Type 2, 9 non-ambulant SMA Type 3 and 19 ambulant SMA Type 3. Collecting these data at nine sites in France, Germany and Belgium established the feasibility of gathering consistent data from numerous and demanding assessments in a multicenter SMA study. Most assessments discriminated between the four groups well. This included the Motor Function Measure (MFM), pulmonary function testing, strength, electroneuromyography, muscle imaging and workspace volume. Additionally, all of the assessments showed good correlation with the MFM score. As the untreated patient population decreases, having reliable and valid multi-site data will be imperative for recruitment in clinical trials. The pending two-year study results will evaluate the sensitivity of the studied outcomes and biomarkers to disease progression.
ClinicalTrials.gov (NCT02391831).
Aims
Sphingosine‐1‐phosphate receptor (S1PR) modulating therapies are currently in the clinic or undergoing investigation for multiple sclerosis (MS) treatment. However, the expression of S1PRs is ...still unclear in the central nervous system under normal conditions and during neuroinflammation.
Methods
Using immunohistochemistry we examined tissues from both grey and white matter MS lesions for sphingosine‐1‐phosphate receptor 1 (S1P1) and 5 (S1P5) expression. Tissues from Alzheimer's disease (AD) cases were also examined.
Results
S1P1 expression was restricted to astrocytes and endothelial cells in control tissues and a decrease in endothelial cell expression was found in white matter MS lesions. In grey matter MS lesions, astrocyte expression was lost in active lesions, while in quiescent lesions it was restored to normal expression levels. CNPase colocalization studies demonstrated S1P5 expression on myelin and both were reduced in demyelinated lesions. In AD tissues we found no difference in S1P1 expression.
Conclusion
These data demonstrate a differential modulation of S1PRs in MS lesions, which may have an impact on S1PR‐directed therapies.
Introduction
To investigate the validity and reliability of the 32-item Motor Function Measure (MFM32) in individuals with neuromuscular disorders (NMD), including spinal muscular atrophy (SMA), aged ...2–5 years, and in non-ambulant individuals with Types 2 or 3 SMA, aged 2–25 years.
Methods
Test–retest reliability (intraclass correlation coefficient ICC), internal consistency (Cronbach’s alpha
α
), convergent validity (Spearman rank-order correlations), and known-groups validity (analysis of covariance comparing groups defined by the Clinical Global Impression of Severity CGI-S scale and Vignos grade) were calculated. The analysis was performed on a dataset provided by Hospices Civils De Lyon, extracted from the multinational MFM32 database. A total of 165 individuals were included in the analyses, of whom 84 were in the NMD group (aged 2–5 years) and 81 were in the SMA group (aged 2–25 years).
Results
Strong evidence of test–retest reliability (ICC: 2- to 5-years’ population = 0.94–0.95; 2- to 25-years’ population = 0.97), internal consistency (Cronbach’s
α
: 2- to 5-years’ population = 0.96; 2- to 25-years’ population = 0.95), convergent validity (2- to 5-years’ population: CGI-S rho = − 0.84, Vignos grade rho = − 0.79; 2- to 25-years’ population: CGI-S rho = − 0.49), and known-groups validity (all
P
< 0.001) were demonstrated.
Conclusions
These analyses provide supportive evidence of the validity and reliability of the MFM32 in younger individuals with NMDs, aged 2–5 years, and in non-ambulant individuals with Types 2 or 3 SMA, aged 2–25 years, supporting the use of the MFM32 across a wide age range.
Objective
To characterize the natural history of spinal muscular atrophy (SMA) over 24 months using innovative measures such as wearable devices, and to provide evidence for the sensitivity of these ...measures to determine their suitability as endpoints in clinical trials.
Methods
Patients with Type 2 and 3 SMA (N = 81) with varied functional abilities (sitters, nonsitters, nonambulant, and ambulant) who were not receiving disease‐modifying treatment were assessed over 24 months: motor function (Motor Function Measure MFM), upper limb strength (MyoGrip, MyoPinch), upper limb activity (ActiMyo®), quantitative magnetic resonance imaging (fat fraction FFT2 mapping and contractile cross‐sectional area C‐CSA), pulmonary function (forced vital capacity FVC, peak cough flow, maximum expiratory pressure, maximum inspiratory pressure, and sniff nasal inspiratory pressure), and survival of motor neuron (SMN) protein levels.
Results
MFM32 scores declined significantly over 24 months, but not 12 months. Changes in upper limb activity could be detected over 6 months and continued to decrease significantly over 12 months, but not 24 months. Upper limb strength decreased significantly over 12 and 24 months. FVC declined significantly over 12 months, but not 24 months. FFT2 increased over 12 and 24 months, although not with statistical significance. A significant increase in C‐CSA was observed at 12 but not 24 months. Blood SMN protein levels were stable over 12 and 24 months.
Interpretation
These data demonstrate that the MFM32, MyoGrip, MyoPinch, and ActiMyo® enable the detection of a significant decline in patients with Type 2 and 3 SMA over 12 or 24 months.
Amyloid-β (Aβ) immunotherapy lowers cerebral Aβ and improves cognition in mouse models of Alzheimer's disease (AD). A clinical trial using active immunization with Aβ1–42 was suspended after ∼6% of ...patients developed meningoencephalitis, possibly because of a T-cell reaction against Aβ. Nevertheless, beneficial effects were reported in antibody responders. Consequently, alternatives are required for a safer vaccine. The Aβ1–15 sequence contains the antibody epitope(s) but lacks the T-cell reactive sites of full-length Aβ1–42. Therefore, we tested four alternative peptide immunogens encompassing either a tandem repeat of two lysine-linked Aβ1–15 sequences (2×Aβ1–15) or the Aβ1–15 sequence synthesized to a cross-species active T1 T-helper-cell epitope (T1-Aβ1–15) and each with the addition of a three-amino-acid RGD (Arg-Gly-Asp) motif (R-2×Aβ1–15; T1-R-Aβ1–15). High anti-Aβ antibody titers were observed in wild-type mice after intranasal immunization with R-2×Aβ1–15 or 2×Aβ1–15 plus mutant
Escherichia coli
heat-labile enterotoxin LT(R192G) adjuvant. Moderate antibody levels were induced after immunization with T1-R-Aβ1–15 or T1-Aβ1–15 plus LT(R192G). Restimulation of splenocytes with the corresponding immunogens resulted in moderate proliferative responses, whereas proliferation was absent after restimulation with full-length Aβ or Aβ1–15. Immunization of human amyloid precursor protein, familial AD (hAPP
FAD
) mice with R-2×Aβ1–15 or 2×Aβ1–15 resulted in high anti-Aβ titers of noninflammatory T-helper 2 isotypes (IgG1 and IgG2b), a lack of splenocyte proliferation against full-length Aβ, significantly reduced Aβ plaque load, and lower cerebral Aβ levels. In addition, 2×Aβ1–15-immunized hAPP
FAD
animals showed improved acquisition of memory compared with vehicle controls in a reference-memory Morris water-maze behavior test that approximately correlated with anti-Aβ titers. Thus, our novel immunogens show promise for future AD vaccines.
Amyloid β (Aβ) protein immunotherapy lowers cerebral Aβ and improves cognition in mouse models of Alzheimer's disease (AD). Here we show that Caribbean vervet monkeys (
Chlorocebus aethiops, SK) ...develop cerebral Aβ plaques with aging and that these deposits are associated with gliosis and neuritic dystrophy. Five aged vervets were immunized with Aβ peptide over 10 months. Plasma and cerebral spinal fluid (CSF) samples were collected periodically from the immunized vervets and five aged controls; one monkey per group expired during the study. By Day 42, immunized animals generated plasma Aβ antibodies that labeled Aβ plaques in human, AD transgenic mouse and vervet brains; bound Aβ1–7; and recognized monomeric and oligomeric Aβ but not full-length amyloid precursor protein nor its C-terminal fragments. Low anti-Aβ titers were detected in CSF. Aβx-40 levels were elevated ∼2- to 5-fold in plasma and decreased up to 64% in CSF in immunized vervets. Insoluble Aβx-42 was decreased by 66% in brain homogenates of the four immunized animals compared to archival tissues from 13 age-matched control vervets. Aβ42-immunoreactive plaques were detected in frontal cortex in 11 of the 13 control animals, but not in six brain regions examined in each of the four immunized vervets. No T cell response or inflammation was observed. Our study is the first to demonstrate age-related Aβ deposition in the vervet monkey as well as the lowering of cerebral Aβ by Aβ vaccination in a non-human primate. The findings further support Aβ immunotherapy as a potential prevention and treatment of AD.
Abstract
Background
Activation of microglia is a part of the inflammatory response in neurodegenerative diseases but its role in the pathophysiology of these diseases is still unclear. The ...osteopetrotic (op/op) mouse lacks colony-stimulating factor-1 (CSF-1) and thus has a deficiency in microglia and macrophages. Prior reports have demonstrated that op/op mice deposit amyloid β (Aβ) plaques, similar to those found in Alzheimer's disease. The purpose of these studies was to confirm this and to determine if the lack of CSF-1 affects the development of dopaminergic neurons and the expression of CD200, a known microglial inhibitory protein.
Method
We examined the central nervous system of op/op mice at 30 days, 60 days and 7 months of age and wildtype littermates at 30 days using immunohistochemistry and histochemistry.
Results
We found a decrease in the number of microglia in 1 month-old op/op mice compared to wildtype (WT) littermates as measured by CD11b, CD45, CD32/16, CD68, CD204 and F4/80 immunoreactivity. Aβ plaques were not detected, while the number of dopaminergic neurons appeared normal. The expression of CD200 appeared to be normal, but there appeared to be a lower expression in the substantia nigra.
Conclusion
In contrast to a prior report we did not detect Aβ deposition in the central nervous system of op/op mice at 30 days, 60 days or 7 months of age and there was a normal number of dopaminergic neurons. This indicates that op/op mice may be useful to examine the effects of microglia on neurodegenerative disease progression by breeding them to different transgenic mouse models. In addition, the lack of CSF-1 does not appear to affect CD200 expression by neurons but we did note a decrease in the substantia nigra of op/op and WT mice, suggesting that this may be a mechanism by which microglia control may be attenuated in this specific area during Parkinson's disease.
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