The functional impact of LGI1 autoantibodies on human CA3 pyramidal neurons

Electrophysiological Recording Protocols

IMPORTANT NOTE: All recording names and identifiers have been anonymized or modified to comply with legal, ethical, and institutional requirements regarding human brain tissue. No personally identifiable information is included.

This repository contains raw electrophysiological recordings obtained from ex vivo human hippocampal slices. Recordings were performed from visually identified CA3 pyramidal neurons or from the CA3 pyramidal layer and were used to assess intrinsic neuronal excitability, synaptic activity, and spontaneous network dynamics.
All electrophysiological recordings are listed with their corresponding recording name, protocol type, and experimental condition in the pdf file named “Recording_Metadata_and_Conditions”.

1. Current-Clamp Current-Step (I–V) Protocol
Recording type: Current-clamp current-step recording
Purpose: Assessment of passive membrane properties and action potential firing
Neurons were recorded in whole-cell current-clamp configuration. A series of square current injections was applied to elicit voltage responses and action potential firing. This protocol was used to quantify resting membrane potential, input resistance, rheobase, membrane time constant, voltage sag, firing frequency, and action potential waveform properties (threshold, amplitude, half-width, rise and decay times, fast afterhyperpolarization), as well as subthreshold excitability parameters.

2. Miniature Excitatory Postsynaptic Currents (mEPSCs)
Recording type: Voltage-clamp mEPSC recording
Purpose: Measurement of spontaneous excitatory synaptic activity
Neurons were recorded in whole-cell voltage-clamp configuration and held at −70 mV. Miniature excitatory postsynaptic currents were recorded in the presence of tetrodotoxin to block action potential-dependent synaptic transmission and additional synaptic blockers to isolate AMPA receptor-mediated events. These recordings were used to analyze mEPSC frequency and amplitude.

3. Local Field Potential (LFP) Recordings
Recording type: Extracellular LFP recording
Purpose: Assessment of spontaneous network activity
Local field potential recordings were obtained from the CA3 pyramidal layer using extracellular electrodes. Recordings were continuous and typically lasted at least 20 minutes. The last 5 minutes LFP traces were analyzed to quantify spontaneous network events, including event amplitude and inter-event intervals.

4. Immunohistochemistry of Biocytin-Filled Neurons
A subset of CA3 pyramidal neurons was filled with biocytin during patch-clamp recordings for morphological reconstruction. After recordings, slices were fixed and immunohistochemistry was performed using streptavidin-conjugated fluorophores to visualize biocytin-labeled neurons.