Dataset Information

Naturally occurring antibodies isolated from PD patients inhibit synuclein seeding in vitro and recognize Lewy pathology.

ABSTRACT: Deposition of ?-synuclein into Lewy bodies and Lewy neurites is the hallmark of Parkinson's disease (PD). It is hypothesized that ?-synuclein pathology spreads by a "prion-like" mechanism (i.e., by seeded aggregation or templated misfolding). Therefore, various extracellular ?-synuclein conformers and/or posttranslational modifications may serve as biomarkers of disease or potential targets for novel interventions. To explore whether the antibody repertoires of PD patients contain anti-?-synuclein antibodies that can potentially be used as markers or immunotherapy, we interrogated peripheral IgG+ memory B cells from PD patients for reactivity to ?-synuclein. In total, ten somatically mutated antibodies were recovered, suggesting the presence of an ongoing antigen-driven immune response. The three antibodies that had the highest affinity to recombinant full-length ?-synuclein, aSyn-323.1, aSyn-336.1 and aSyn-338.1, were characterized further and shown to recognize epitopes in the C terminus of ?-synuclein with binding affinities between 0.3 and 2.8 ?M. Furthermore, all three antibodies were able to neutralize the "seeding" of intracellular synuclein aggregates in an in vitro ?-synuclein seeding assay. Finally, differential reactivities were observed for all three human anti-?-synuclein antibodies across tissue treatment conditions by immunohistochemistry. Our results suggest that the memory B-cell repertoire of PD patients might represent a potential source of biomarkers and therapies.

SUBMITTER: Li X

PROVIDER: S-EPMC6482120 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Naturally occurring antibodies isolated from PD patients inhibit synuclein seeding in vitro and recognize Lewy pathology.

Li Xinyi X Koudstaal Wouter W Fletcher Lauren L Costa Martha M van Winsen Margot M Siregar Berdien B Inganäs Hanna H Kim Julie J Keogh Elissa E Macedo Jeremy J Holland Trevin T Perry Stuart S Bard Frederique F Hoozemans Jeroen J JJ Goudsmit Jaap J Apetri Adrian A Pascual Gabriel G

Acta neuropathologica 20190225 5

Deposition of α-synuclein into Lewy bodies and Lewy neurites is the hallmark of Parkinson's disease (PD). It is hypothesized that α-synuclein pathology spreads by a "prion-like" mechanism (i.e., by seeded aggregation or templated misfolding). Therefore, various extracellular α-synuclein conformers and/or posttranslational modifications may serve as biomarkers of disease or potential targets for novel interventions. To explore whether the antibody repertoires of PD patients contain anti-α-synucle ...[more]

PMID: 30805666

Similar Datasets

Project description:The clinicopathological heterogeneity in Lewy-body diseases (LBD) highlights the need for pathology-driven biomarkers in-vivo. Misfolded alpha-synuclein (α-Syn) is a lead candidate based on its crucial role in disease pathophysiology. Real-time quaking-induced conversion (RT-QuIC) analysis of CSF has recently shown high sensitivity and specificity for the detection of misfolded α-Syn in patients with Parkinson's disease (PD) and dementia with Lewy bodies (DLB). In this study we performed the CSF RT-QuIC assay in 236 PD and 49 DLB patients enriched for different genetic forms with mutations in GBA, parkin, PINK1, DJ1, and LRRK2. A subgroup of 100 PD patients was also analysed longitudinally. We correlated kinetic seeding parameters of RT-QuIC with genetic status and CSF protein levels of molecular pathways linked to α-Syn proteostasis. Overall, 85% of PD and 86% of DLB patients showed positive RT-QuIC α-Syn seeding activity. Seeding profiles were significantly associated with mutation status across the spectrum of genetic LBD. In PD patients, we detected positive α-Syn seeding in 93% of patients carrying severe GBA mutations, in 78% with LRRK2 mutations, in 59% carrying heterozygous mutations in recessive genes, and in none of those with bi-allelic mutations in recessive genes. Among PD patients, those with severe GBA mutations showed the highest seeding activity based on RT-QuIC kinetic parameters and the highest proportion of samples with 4 out of 4 positive replicates. In DLB patients, 100% with GBA mutations showed positive α-Syn seeding compared to 79% of wildtype DLB. Moreover, we found an association between α-Syn seeding activity and reduced CSF levels of proteins linked to α-Syn proteostasis, specifically lysosome-associated membrane glycoprotein 2 and neurosecretory protein VGF.These findings highlight the value of α-Syn seeding activity as an in-vivo marker of Lewy-body pathology and support its use for patient stratification in clinical trials targeting α-Syn.

Project description:BACKGROUND:Abnormal aggregation of proteins induces neuronal cell loss in neurodegenerative disorders such as Alzheimer's Disease, Creutzfeldt-Jakob Disease and Parkinson's Disease. Specific stimuli initialize conformational changes in physiological proteins, causing intra- or extracellular protein aggregation. We and other groups have identified naturally occurring autoantibodies (nAbs) as part of the human antibody pool that are able to prevent peptide fibrillation. These nAbs show a rescue effect following exposure of toxic aggregates on neurons, and they support microglial uptake of aggregated peptides. OBJECTIVE:Identification of a putative common epitope among the relevant proteins ?-Amyloid, ?-Synuclein and Prion Protein for the respective nAbs. MATERIAL AND METHODS:Binding affinity between the aforementioned proteins and nAbs was tested by Dot Blot, ELISA and SPR-technology. Furthermore, the functionality of the protein-nAbs-complexes was studied in Thioflavin-T assays and microglial uptake experiments to study dependent inhibition of protein aggregation and enhancement of Fc? mediated uptake by microglial cells. RESULTS:?-Amyloid and Prion Protein fragment showed considerable binding affinity and functional efficacy for all applied nAbs. Thereby, no significant difference within the different nAbs was detected. In contrast, ?-Synuclein was bound exclusively by nAbs-?-Synuclein, which was reproduced in all binding studies. Surprisingly, functional assays with ?-Synuclein revealed no significant effect of nAbs in comparison to IVIg treatment. However, all applied nAbs as well as IVIg show a minimal functionality on the microglial uptake of ?-Synuclein. CONCLUSION:nAbs-A?, nAbs-PrP possibly display comparable affinity to the same structural epitope within A? and PrP106-126 A117V whereas the epitope recognized by nAbs-?-Syn is only present in ?-Syn. The structural similarity of A? and PrP fragment promotes the outline for an efficient antibody for the treatment of several neurodegenerative disorders and extend the functional characteristics of the investigated nAbs.

Dataset Information

Naturally occurring antibodies isolated from PD patients inhibit synuclein seeding in vitro and recognize Lewy pathology.

Publications

Naturally occurring antibodies isolated from PD patients inhibit synuclein seeding in vitro and recognize Lewy pathology.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets