LSO:Ce Inorganic Scintillators Are Biocompatible With Neuronal and Circuit Function

Area of Science:

• Neuroscience
• Biomaterials
• Optogenetics

Background:

• Optogenetics requires precise neural circuit control but faces challenges with invasive light delivery methods.
• Non-invasive light delivery is crucial for advancing optogenetic applications in neuroscience.
• Radioluminescent particles (RPLs) offer a potential solution for localized light generation within the brain.

Purpose of the Study:

• To investigate the biocompatibility and efficacy of cerium-doped lutetium oxyorthosilicate (LSO:Ce) inorganic scintillator particles for optogenetics.
• To assess the impact of LSO:Ce particles on neuronal processes and synaptic function.
• To demonstrate the potential of LSO:Ce particles as a novel non-invasive light delivery system for optogenetics.

Main Methods:

• Cellular, molecular, and electrophysiological approaches were used to evaluate LSO:Ce particle effects.
• Whole-cell recordings of CA1 pyramidal cells were performed with UV stimulation of LSO:Ce particles in ChR2-expressing hippocampal slices.
• Neuronal survival, synaptic transmission (excitatory and inhibitory), and long-term potentiation (LTP) were assessed.

Main Results:

• LSO:Ce particles did not affect primary cortical neuron survival after 24h exposure.
• UV stimulation of LSO:Ce particles successfully activated channelrhodopsin-2 (ChR2), increasing excitatory postsynaptic currents (sEPSCs) frequency and amplitude.
• Modest effects on baseline synaptic function and LTP magnitude were observed, but LSO:Ce particles were shown to be biocompatible.

Conclusions:

• LSO:Ce inorganic scintillator particles are biocompatible and can activate ChR2 for optogenetic manipulation.
• These particles represent a promising new avenue for non-invasive light delivery in optogenetics.
• Further research may optimize LSO:Ce particles for enhanced synaptic function and plasticity modulation.