LGI1 Autoantibodies Enhance Synaptic Transmission by Presynaptic K
Autoantibodies
/ immunology
Humans
Animals
Synaptic Transmission
/ physiology
Intracellular Signaling Peptides and Proteins
/ immunology
Presynaptic Terminals
/ metabolism
Action Potentials
/ physiology
Hippocampus
/ metabolism
Rats
Kv1.1 Potassium Channel
/ immunology
Proteins
/ immunology
Male
Cells, Cultured
Journal
Neurology(R) neuroimmunology & neuroinflammation
ISSN: 2332-7812
Titre abrégé: Neurol Neuroimmunol Neuroinflamm
Pays: United States
ID NLM: 101636388
Informations de publication
Date de publication:
Sep 2024
Sep 2024
Historique:
medline:
14
8
2024
pubmed:
14
8
2024
entrez:
14
8
2024
Statut:
ppublish
Résumé
Autoantibodies against the protein leucine-rich glioma inactivated 1 (LGI1) cause the most common subtype of autoimmune encephalitis with predominant involvement of the limbic system, associated with seizures and memory deficits. LGI1 and its receptor ADAM22 are part of a transsynaptic protein complex that includes several proteins involved in presynaptic neurotransmitter release and postsynaptic glutamate sensing. Autoantibodies against LGI1 increase excitatory synaptic strength, but studies that genetically disrupt the LGI1-ADAM22 complex report a reduction in postsynaptic glutamate receptor-mediated responses. Thus, the mechanisms underlying the increased synaptic strength induced by LGI1 autoantibodies remain elusive, and the contributions of presynaptic molecules to the LGI1-transsynaptic complex remain unclear. We therefore investigated the presynaptic mechanisms that mediate autoantibody-induced synaptic strengthening. We studied the effects of patient-derived purified polyclonal LGI1 autoantibodies on synaptic structure and function by combining direct patch-clamp recordings from presynaptic boutons and somata of hippocampal neurons with super-resolution light and electron microscopy of hippocampal cultures and brain slices. We also identified the protein domain mediating the presynaptic effect using domain-specific patient-derived monoclonal antibodies. LGI1 autoantibodies dose-dependently increased short-term depression during high-frequency transmission, consistent with increased release probability. The increased neurotransmission was not related to presynaptic calcium channels because presynaptic Ca Our results indicate that LGI1 autoantibodies reduce the density of both K
Sections du résumé
BACKGROUND AND OBJECTIVES
OBJECTIVE
Autoantibodies against the protein leucine-rich glioma inactivated 1 (LGI1) cause the most common subtype of autoimmune encephalitis with predominant involvement of the limbic system, associated with seizures and memory deficits. LGI1 and its receptor ADAM22 are part of a transsynaptic protein complex that includes several proteins involved in presynaptic neurotransmitter release and postsynaptic glutamate sensing. Autoantibodies against LGI1 increase excitatory synaptic strength, but studies that genetically disrupt the LGI1-ADAM22 complex report a reduction in postsynaptic glutamate receptor-mediated responses. Thus, the mechanisms underlying the increased synaptic strength induced by LGI1 autoantibodies remain elusive, and the contributions of presynaptic molecules to the LGI1-transsynaptic complex remain unclear. We therefore investigated the presynaptic mechanisms that mediate autoantibody-induced synaptic strengthening.
METHODS
METHODS
We studied the effects of patient-derived purified polyclonal LGI1 autoantibodies on synaptic structure and function by combining direct patch-clamp recordings from presynaptic boutons and somata of hippocampal neurons with super-resolution light and electron microscopy of hippocampal cultures and brain slices. We also identified the protein domain mediating the presynaptic effect using domain-specific patient-derived monoclonal antibodies.
RESULTS
RESULTS
LGI1 autoantibodies dose-dependently increased short-term depression during high-frequency transmission, consistent with increased release probability. The increased neurotransmission was not related to presynaptic calcium channels because presynaptic Ca
DISCUSSION
CONCLUSIONS
Our results indicate that LGI1 autoantibodies reduce the density of both K
Identifiants
pubmed: 39141878
doi: 10.1212/NXI.0000000000200284
doi:
Substances chimiques
Autoantibodies
0
LGI1 protein, human
0
Intracellular Signaling Peptides and Proteins
0
Kv1.1 Potassium Channel
147173-20-4
Proteins
0
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM