Erasable Serum Markers

Area of Science:

• Neuroscience
• Biotechnology
• Molecular Biology

Background:

• Brain gene expression is typically assessed invasively.
• Existing serum markers lack specificity and dynamic range.
• Long serum half-lives of markers hinder monitoring temporal changes.

Purpose of the Study:

• To develop a novel method for sensitive, non-invasive monitoring of brain gene expression.
• To engineer erasable serum markers (ESM) for improved dynamic range.
• To enable precise tracking of transgene expression and neural activity.

Main Methods:

• Developed released markers of activity (RMAs) for transgene expression measurement.
• Engineered on-demand erasable RMAs.
• Administered an intravenous targeted protease to reduce RMA background signal.
• Validated detection sensitivity using a low-level promoter activity model.

Main Results:

• RMAs detect transgene expression from as few as 12 neurons in mice.
• Erasable RMAs reduced background signal by over an order of magnitude.
• The system achieved a 65,000-fold signal increase over baseline in a single brain region.
• Improved dynamic range for detecting low-level promoter activity.

Conclusions:

• Erasable serum markers (ESM) offer a sensitive and dynamic non-invasive method for monitoring brain gene expression.
• This approach overcomes limitations of traditional serum markers and invasive techniques.
• ESM technology enhances the ability to track neural activity and gene expression changes in vivo.