Evaluation of Antisense Oligonucleotide-Associated Neuronal Lysosomal Changes

Area of Science:

• Neuroscience
• Cell Biology
• Pharmacology

Background:

• Antisense oligonucleotides (ASOs) are emerging therapeutics targeting gene expression.
• ASO cellular uptake involves endocytosis, leading to the endolysosomal pathway.
• Understanding long-term cellular effects of ASOs is crucial for therapeutic development.

Purpose of the Study:

• To investigate the impact of repeated antisense oligonucleotide (ASO) exposure on the endolysosomal system.
• To characterize cellular and molecular changes in neurons following ASO administration.

Main Methods:

• Histological and electron microscopy examination of nonhuman primate brain and spinal cord tissue.
• Development of an induced pluripotent stem cell-derived motor neuron (iPSC-MN) model.
• Lipidomic and proteomic analysis of lysosomes isolated from ASO-treated iPSC-MNs.

Main Results:

• Dose-related neuronal microvesicular vacuolation observed in nonhuman primates, particularly in the hippocampus, cortex, and spinal cord.
• Lysosomes in affected neurons contained stacked membranous material.
• ASO treatment in iPSC-MNs led to increased bis(monoacylglycerol)phosphate and lactosylceramide, and decreased lysosomal hydrolases, without impacting cell viability.

Conclusions:

• Repeated ASO administration induces specific lysosomal changes in neurons.
• The iPSC-MN model effectively recapitulates ASO-induced lysosomal alterations.
• These findings provide insights into the cellular consequences of prolonged ASO therapy and inform future safety assessments.