Lighting up ATP in cells and tissues using a simple aptamer-based fluorescent probe

Area of Science:

• Biochemistry
• Molecular Biology
• Biomedical Engineering

Background:

• Extracellular adenosine triphosphate (ATP) acts as a purinergic signaling molecule involved in tumor progression, therapy resistance, and immune suppression.
• ATP is a key indicator of cellular energy status and viability, critical for tissue regeneration and in vitro tissue engineering.
• COVID-19 virus infection is associated with ATP deficit and release, contributing to disease complications.

Purpose of the Study:

• To develop a sensitive and selective fluorescence "signal-on" probe for detecting and imaging adenosine triphosphate (ATP).
• To explore the probe's utility in cellular imaging and its application in cardio-tissue engineering for assessing cellular ATP status.
• To investigate probe modifications for potential regeneration capabilities.

Main Methods:

• Construction of a "signal-on" fluorescent probe utilizing a black hole quencher (BHQ)-labeled aptamer and a fluorophore (Cy5)-labeled reporter flare.
• Detection of ATP in solution with a single-digit µM detection limit.
• Cellular uptake and imaging in U2OS cells using lipofectamine; application in cardio-tissue engineering.

Main Results:

• The developed probe demonstrated sensitive ATP detection in solution (single-digit µM limit).
• Efficient cellular entry and fluorescence imaging were achieved in U2OS cells within 3 hours.
• The probe semi-quantitatively sensed cellular ATP status in cardio-tissue engineering, aiding cardiomyocyte selection.

Conclusions:

• The developed probe is effective for ATP detection and imaging in various biological and clinical contexts.
• This probe offers a novel approach for monitoring cellular ATP in tissue engineering, particularly for selecting functional cardiomyocytes.
• Probe modifications show potential for applications requiring ATP measurement and regeneration capabilities.