TY - JOUR A1 - McFleder, Rhonda L. A1 - Makhotkina, Anastasiia A1 - Groh, Janos A1 - Keber, Ursula A1 - Imdahl, Fabian A1 - Peña Mosca, Josefina A1 - Peteranderl, Alina A1 - Wu, Jingjing A1 - Tabuchi, Sawako A1 - Hoffmann, Jan A1 - Karl, Ann-Kathrin A1 - Pagenstecher, Axel A1 - Vogel, Jörg A1 - Beilhack, Andreas A1 - Koprich, James B. A1 - Brotchie, Jonathan M. A1 - Saliba, Antoine-Emmanuel A1 - Volkmann, Jens A1 - Ip, Chi Wang T1 - Brain-to-gut trafficking of alpha-synuclein by CD11c\(^+\) cells in a mouse model of Parkinson’s disease JF - Nature Communications N2 - Inflammation in the brain and gut is a critical component of several neurological diseases, such as Parkinson’s disease (PD). One trigger of the immune system in PD is aggregation of the pre-synaptic protein, α-synuclein (αSyn). Understanding the mechanism of propagation of αSyn aggregates is essential to developing disease-modifying therapeutics. Using a brain-first mouse model of PD, we demonstrate αSyn trafficking from the brain to the ileum of male mice. Immunohistochemistry revealed that the ileal αSyn aggregations are contained within CD11c+ cells. Using single-cell RNA sequencing, we demonstrate that ileal CD11c\(^+\) cells are microglia-like and the same subtype of cells is activated in the brain and ileum of PD mice. Moreover, by utilizing mice expressing the photo-convertible protein, Dendra2, we show that CD11c\(^+\) cells traffic from the brain to the ileum. Together these data provide a mechanism of αSyn trafficking between the brain and gut. KW - antigen-presenting cells KW - neuroimmunology KW - Parkinson's disease Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357696 VL - 14 ER - TY - JOUR A1 - Badr, Mohammad A1 - McFleder, Rhonda L. A1 - Wu, Jingjing A1 - Knorr, Susanne A1 - Koprich, James B. A1 - Hünig, Thomas A1 - Brotchie, Jonathan M. A1 - Volkmann, Jens A1 - Lutz, Manfred B. A1 - Ip, Chi Wang T1 - Expansion of regulatory T cells by CD28 superagonistic antibodies attenuates neurodegeneration in A53T-α-synuclein Parkinson’s disease mice JF - Journal of Neuroinflammation N2 - Background Regulatory CD4\(^+\)CD25\(^+\)FoxP3\(^+\) T cells (Treg) are a subgroup of T lymphocytes involved in maintaining immune balance. Disturbance of Treg number and impaired suppressive function of Treg correlate with Parkinson’s disease severity. Superagonistic anti-CD28 monoclonal antibodies (CD28SA) activate Treg and cause their expansion to create an anti-inflammatory environment. Methods Using the AAV1/2-A53T-α-synuclein Parkinson’s disease mouse model that overexpresses the pathogenic human A53T-α-synuclein (hαSyn) variant in dopaminergic neurons of the substantia nigra, we assessed the neuroprotective and disease-modifying efficacy of a single intraperitoneal dose of CD28SA given at an early disease stage. Results CD28SA led to Treg expansion 3 days after delivery in hαSyn Parkinson’s disease mice. At this timepoint, an early pro-inflammation was observed in vehicle-treated hαSyn Parkinson’s disease mice with elevated percentages of CD8\(^+\)CD69\(^+\) T cells in brain and increased levels of interleukin-2 (IL-2) in the cervical lymph nodes and spleen. These immune responses were suppressed in CD28SA-treated hαSyn Parkinson’s disease mice. Early treatment with CD28SA attenuated dopaminergic neurodegeneration in the SN of hαSyn Parkinson’s disease mice accompanied with reduced brain numbers of activated CD4\(^+\), CD8\(^+\) T cells and CD11b\(^+\) microglia observed at the late disease-stage 10 weeks after AAV injection. In contrast, a later treatment 4 weeks after AAV delivery failed to reduce dopaminergic neurodegeneration. Conclusions Our data indicate that immune modulation by Treg expansion at a timepoint of overt inflammation is effective for treatment of hαSyn Parkinson’s disease mice and suggest that the concept of early immune therapy could pose a disease-modifying option for Parkinson’s disease patients. KW - Parkinson’s disease KW - neuroinflammation KW - T cells KW - regulatory T cells KW - neuroprotection Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300580 VL - 19 ER - TY - JOUR A1 - Karikari, Akua A. A1 - McFleder, Rhonda L. A1 - Ribechini, Eliana A1 - Blum, Robert A1 - Bruttel, Valentin A1 - Knorr, Susanne A1 - Gehmeyr, Mona A1 - Volkmann, Jens A1 - Brotchie, Jonathan M. A1 - Ahsan, Fadhil A1 - Haack, Beatrice A1 - Monoranu, Camelia-Maria A1 - Keber, Ursula A1 - Yeghiazaryan, Rima A1 - Pagenstecher, Axel A1 - Heckel, Tobias A1 - Bischler, Thorsten A1 - Wischhusen, Jörg A1 - Koprich, James B. A1 - Lutz, Manfred B. A1 - Ip, Chi Wang T1 - Neurodegeneration by α-synuclein-specific T cells in AAV-A53T-α-synuclein Parkinson’s disease mice JF - Brain, Behavior, and Immunity N2 - Background Antigen-specific neuroinflammation and neurodegeneration are characteristic for neuroimmunological diseases. In Parkinson’s disease (PD) pathogenesis, α-synuclein is a known culprit. Evidence for α-synuclein-specific T cell responses was recently obtained in PD. Still, a causative link between these α-synuclein responses and dopaminergic neurodegeneration had been lacking. We thus addressed the functional relevance of α-synuclein-specific immune responses in PD in a mouse model. Methods We utilized a mouse model of PD in which an Adeno-associated Vector 1/2 serotype (AAV1/2) expressing human mutated A53T-α-Synuclein was stereotactically injected into the substantia nigra (SN) of either wildtype C57BL/6 or Recombination-activating gene 1 (RAG1)\(^{-/-}\) mice. Brain, spleen, and lymph node tissues from different time points following injection were then analyzed via FACS, cytokine bead assay, immunohistochemistry and RNA-sequencing to determine the role of T cells and inflammation in this model. Bone marrow transfer from either CD4\(^{+}\)/CD8\(^{-}\), CD4\(^{-}\)/CD8\(^{+}\), or CD4\(^{+}\)/CD8\(^{+}\) (JHD\(^{-/-}\)) mice into the RAG-1\(^{-/-}\) mice was also employed. In addition to the in vivo studies, a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay was utilized. Results AAV-based overexpression of pathogenic human A53T-α-synuclein in dopaminergic neurons of the SN stimulated T cell infiltration. RNA-sequencing of immune cells from PD mouse brains confirmed a pro-inflammatory gene profile. T cell responses were directed against A53T-α-synuclein-peptides in the vicinity of position 53 (68–78) and surrounding the pathogenically relevant S129 (120–134). T cells were required for α-synuclein-induced neurodegeneration in vivo and in vitro, while B cell deficiency did not protect from dopaminergic neurodegeneration. Conclusions Using T cell and/or B cell deficient mice and a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay, we confirmed in vivo and in vitro that pathogenic α-synuclein peptide-specific T cell responses can cause dopaminergic neurodegeneration and thereby contribute to PD-like pathology. KW - Parkinson’s disease KW - α-synuclein-specific T cells KW - neurodegeneration Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300600 VL - 101 SP - 194 EP - 210 ER -