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Inflammation contributes to Parkinson’s disease pathogenesis. We hypothesized that B lymphocytes are involved in Parkinson’s disease progression. We measured antibodies to alpha-synuclein and tau in serum from patients with rapid eye movement sleep behaviour disorder (n = 79), early Parkinson’s disease (n = 50) and matched controls (n = 50). Rapid eye movement sleep behaviour disorder cases were stratified by risk of progression to Parkinson’s disease (low risk = 30, high risk = 49). We also measured B-cell activating factor of the tumour necrosis factor receptor family, C-reactive protein and total immunoglobulin G. We found elevated levels of antibodies to alpha-synuclein fibrils in rapid eye movement sleep behaviour disorder patients at high risk of Parkinson’s disease conversion (ANOVA, P < 0.001) and lower S129D peptide-specific antibodies in those at low risk (ANOVA, P < 0.001). An early humoral response to alpha-synuclein is therefore detectable prior to the development of Parkinson’s disease. Peripheral B lymphocyte phenotyping using flow cytometry in early Parkinson’s disease patients and matched controls (n = 41 per group) revealed reduced B cells in Parkinson’s disease, particularly in those at higher risk of developing an early dementia [t(3) = 2.87, P = 0.01]. Patients with a greater proportion of regulatory B cells had better motor scores [F(4,24) = 3.612, P = 0.019], suggesting they have a protective role in Parkinson’s disease. In contrast, B cells isolated from Parkinson’s disease patients at higher risk of dementia had greater cytokine (interleukin 6 and interleukin 10) responses following in vitro stimulation. We assessed peripheral blood lymphocytes in alpha-synuclein transgenic mouse models of Parkinson’s disease: they also had reduced B cells, suggesting this is related to alpha-synuclein pathology. In a toxin-based mouse model of Parkinson’s disease, B-cell deficiency or depletion resulted in worse pathological and behavioural outcomes, supporting the conclusion that B cells play an early protective role in dopaminergic cell loss. In conclusion, we found changes in the B-cell compartment associated with risk of disease progression in rapid eye movement sleep behaviour disorder (higher alpha-synuclein antibodies) and early Parkinson’s disease (lower levels of B lymphocytes that were more reactive to stimulation). Regulatory B cells play a protective role in a mouse model, potentially by attenuating inflammation and dopaminergic cell loss. B cells are therefore likely to be involved in the pathogenesis of Parkinson’s disease, albeit in a complex way, and thus warrant consideration as a therapeutic target.

BACKGROUND: Several reports have identified different patterns of Parkinson's disease progression in individuals carrying missense variants in GBA or LRRK2 genes. The overall contribution of genetic factors to the severity and progression of Parkinson's disease, however, has not been well studied. OBJECTIVES: To test the association between genetic variants and the clinical features of Parkinson's disease on a genomewide scale. METHODS: We accumulated individual data from 12 longitudinal cohorts in a total of 4093 patients with 22,307 observations for a median of 3.81 years. Genomewide associations were evaluated for 25 cross-sectional and longitudinal phenotypes. Specific variants of interest, including 90 recently identified disease-risk variants, were also investigated post hoc for candidate associations with these phenotypes. RESULTS: Two variants were genomewide significant. Rs382940(T>A), within the intron of SLC44A1, was associated with reaching Hoehn and Yahr stage 3 or higher faster (hazard ratio 2.04 [1.58-2.62]; P value = 3.46E-8). Rs61863020(G>A), an intergenic variant and expression quantitative trait loci for α-2A adrenergic receptor, was associated with a lower prevalence of insomnia at baseline (odds ratio 0.63 [0.52-0.75]; P value = 4.74E-8). In the targeted analysis, we found 9 associations between known Parkinson's risk variants and more severe motor/cognitive symptoms. Also, we replicated previous reports of GBA coding variants (rs2230288: p.E365K; rs75548401: p.T408M) being associated with greater motor and cognitive decline over time, and an APOE E4 tagging variant (rs429358) being associated with greater cognitive deficits in patients. CONCLUSIONS: We identified novel genetic factors associated with heterogeneity of Parkinson's disease. The results can be used for validation or hypothesis tests regarding Parkinson's disease. © 2019 International Parkinson and Movement Disorder Society.

BACKGROUNDHuntington’s disease is an autosomal-dominant neurodegenerative disease caused by CAG trinucleotide repeat expansion in HTT, resulting in a mutant huntingtin protein. IONIS-HTTRx (hereafter, HTTRx) is an antisense oligonucleotide designed to inhibit HTT messenger RNA and thereby reduce concentrations of mutant huntingtin.METHODSWe conducted a randomized, double-blind, multiple-ascending-dose, phase 1–2a trial involving adults with early Huntington’s disease. Patients were randomly assigned in a 3:1 ratio to receive HTTRx or placebo as a bolus intrathecal administration every 4 weeks for four doses. Dose selection was guided by a preclinical model in mice and nonhuman primates that related dose level to reduction in the concentration of huntingtin. The primary end point was safety. The secondary end point was HTTRx pharmacokinetics in cerebrospinal fluid (CSF). Prespecified exploratory end points included the concentration of mutant huntingtin in CSF.RESULTSOf the 46 patients who were enrolled in the trial, 34 were randomly assigned to receive HTTRx (at ascending dose levels of 10 to 120 mg) and 12 were randomly assigned to receive placebo. Each patient received all four doses and completed the trial. Adverse events, all of grade 1 or 2, were reported in 98% of the patients. No serious adverse events were seen in HTTRx-treated patients. There were no clinically relevant adverse changes in laboratory variables. Predose (trough) concentrations of HTTRx in CSF showed dose dependence up to doses of 60 mg. HTTRx treatment resulted in a dose-dependent reduction in the concentration of mutant huntingtin in CSF (mean percentage change from baseline, 10% in the placebo group and −20%, −25%, −28%, −42%, and −38% in the HTTRx 10-mg, 30-mg, 60-mg, 90-mg, and 120-mg dose groups, respectively).CONCLUSIONSIntrathecal administration of HTTRx to patients with early Huntington’s disease was not accompanied by serious adverse events. We observed dose-dependent reductions in concentrations of mutant huntingtin. (Funded by Ionis Pharmaceuticals and F. Hoffmann–La Roche; ClinicalTrials.gov number, NCT02519036. opens in new tab.)

Commentary on: Chinta, S. J. Woods, G. Demaria M. et al. Cellular Senescence Is Induced by the Environmental Neurotoxin Paraquat and Contributes to Neuropathology Linked to Parkinson’s Disease. Cell Reports 2018; 22: 930-940. Parkinson’s disease (PD) becomes increasingly common with advancing age. It is therefore possible that cell senescence contributes to its pathophysiology. In a recent paper in Cell Reports, Chinta et al1 have shown that astrocytes exhibiting an age-associated (senescent) phenotype are toxic to neurons in vitro, and their removal is associated with better outcomes in a mouse model of PD. This finding may be relevant to other neurodegenerative conditions such as Alzheimer’s and Amyotrophic Lateral Sclerosis (ALS) in which cellular senescence is also implicated.2

Ugandan bark cloth has been recognised by UNESCO as a masterpiece of the ‘Intangible Cultural Heritage of Humanity’, to protect the knowledge, traditions and livelihoods associated with its production. Bark cloth is a non-woven, fibrous textile that has been produced from the wild fig or mutuba tree (Ficus natalensis) by the Baganda people of southern Uganda for hundreds of years. A typical bark cloth has a rich, terracotta colour and is worn by kings and chiefs during coronations, religious ceremonies and cultural gatherings, as well as for funeral shrouds. This research is part of a project that explores the properties and significance of bark cloth from cultural, ethical, technical and aesthetic perspectives to determine its feasibility as a sustainable fashion textile. It will highlight the potential of bark cloth specifically in relation to the characteristics of luxury fashion (craftsmanship, quality, rarity, heritage and story-telling), through using techniques that include embroidery, appliqué, gilding, laser cutting, natural dyeing and fusing. In addition, the bark cloth has been investigated for its practical suitability for apparel end use. Various fabric tests have been carried out to investigate its performance including fabric drape, stiffness, surface morphology and tearing strength. The material was also subjected to laser etching to implement design patterns. The bark cloth was subjected to CO2 laser etching and sublimation printing to incorporate surface patterns. Based on the trials, an optimum set of parameters were identified to use laser and sublimation printing. As the material is stiff when it is heat-pressed and to facilitate the garment making process the bark cloth was fused with different types of knitted and woven fusible linings, and its drape and strength were also tested. A basic test garment (size 12 female full-sleeve top) was developed with the fused bark cloth that offered good drape and its shape and fit were evaluated on a mannequin. Outcomes indicated that bark cloth could be satisfactorily developed into outer garments with specific treatment. It is anticipated that this research will indirectly create demand for bark cloth from Uganda and help to support the artisans involved in the production of sustainable bark cloth.