Signal amplification methods provide opportunities for sensitive imaging of RNA biomarkers of inflammation. However, conventional amplification approaches lack spatial selectivity to inflamed tissues after the systemic administration of amplifiers, leading to a low signal-to-background ratio.
Recently, a research group led by Prof. LI Lele from the National Center for Nanoscience and Technology (NCNST) of the Chinese Academy of Sciences (CAS) and collaborators have reported an enzymatic-amplification strategy for in vivo imaging of inflammation-associated mRNA in a disease site-specific manner. The study was published in Nature Biomedical Engineering.
In this study, the team designed an enzyme-triggered molecular beacon probe. The probe could produce a one-to-many signal read-out, resulting in sufficient sensitivity for accurate imaging of RNA. Moreover, the signal amplification was performed in a spatially selective manner due to the specific cytoplasmic localization of the enzyme in inflammatory cells.
The researchers presented this enzymatic-amplification strategy to amplify mRNA imaging signals for the diagnosis of acute inflammation and drug-induced hepatotoxicity.
Additionally, this strategy could detect inflammation much earlier than current clinical diagnostic methods including histological and serum biochemical changes.
“Compared with previous amplification approaches, the enzyme-mediated signal amplification method allows to precise control over mRNA imaging at the site of inflammation,” said Prof. LI, “We envisage that our approach could be applied for the diagnosis of different diseases when choosing suitable RNA biomarkers.
Spatially selective imaging of inflammation-associated mRNA via enzymatic triggered fluorescence amplification. (Image by LI Lele et al)
National Center for Nanoscience and Technology