Chemiluminescence-Driven Tyramide Amplification for High-Sensitivity and Long-Term Immunofluorescence Imaging

Area of Science:

• Biotechnology
• Microscopy
• Molecular Biology

Background:

• Immunofluorescence (IF) is crucial for visualizing biomolecules but suffers from photobleaching, photodamage, and autofluorescence.
• These limitations hinder the detection of low-abundance targets and long-term imaging.
• Conventional IF relies on strong external light excitation, causing signal degradation.

Purpose of the Study:

• To introduce ChemTIF, a chemiluminescence-triggered IF method.
• To overcome the limitations of conventional IF imaging.
• To enable high-fidelity longitudinal imaging in spatial proteomics and biomedical research.

Main Methods:

• ChemTIF integrates horseradish peroxidase (HRP)-catalyzed tyramide signal amplification with luminol-based chemiluminescence.
• It utilizes localized chemiluminescence resonance energy transfer to excite fluorophores, eliminating strong external light excitation.
• The method was tested in cellular and tissue models for static and dynamic imaging.

Main Results:

• ChemTIF achieved up to 25-fold signal amplification in cells and 12-fold in tissues.
• It demonstrated significantly reduced background noise and photodamage compared to conventional IF.
• Extended signal duration (up to 33 min in cells, 57 min in tissues) and minimal autofluorescence were observed.

Conclusions:

• ChemTIF offers superior sensitivity and signal duration, outperforming conventional IF.
• Its compatibility with cyclic imaging supports high-throughput applications with minimal photodamage.
• ChemTIF is a robust platform for high-fidelity longitudinal imaging in spatial proteomics and biomedical research.