Intranasal bacteria transport obesity drugs to the brain

Intranasal delivery of brain-targeted therapeutics through the olfactory epithelium (OE) has emerged as a strategy to circumvent the protective blood–brain barrier, but this route of administration is still limited as it requires high and frequent dosing. Writing in Cell, Shen et al. improve OE-mediated delivery to the brain by engineering a bacterial strain that naturally resides inside the nose.

The authors tapped the nasal microbiome to improve OE targeting, identifying the commensal bacterium Lactobacillus plantarum (Lp), which naturally and specifically binds the OE. They first labeled Lp with the tracer molecule FITC to track the transport of potential therapeutic payloads to the OE, showing that after 3 days of daily bacterial administration, FITC accumulated in the lamina propria beneath the OE. After 7 days, it reached the brain at the olfactory bulb, where it accumulated over time while also diffusing to other regions in the brain.

This is a preview of subscription content, access via your institution