Photothermal image flow cytometry in vivo.

Area of Science:

• Biomedical Optics
• Cellular Imaging
• Microcirculation Research

Background:

• Label-free imaging of dynamic biological processes is crucial for understanding cellular function.
• Existing microscopy techniques often require cell labeling, which can alter cell behavior or be unsuitable for in vivo studies.
• Real-time monitoring of circulating cells in microvessels is challenging.

Purpose of the Study:

• To demonstrate the capability of photothermal (PT) microscopy for real-time, in vivo imaging of unlabeled, moving cells.
• To explore the potential of PT microscopy as a novel tool for flow cytometry applications.
• To investigate the dynamics of blood and lymph cells in microcirculation.

Main Methods:

• Utilized photothermal (PT) microscopy to visualize cellular structures based on their light absorption properties.
• Applied the technique to observe circulating red and white blood cells in the blood and lymph microvessels of rat mesentery.
• Recorded real-time movement and interactions of cells within the microvasculature.

Main Results:

• Successfully demonstrated real-time, in vivo imaging of moving, unlabeled red and white blood cells.
• Visualized cellular dynamics within both blood and lymph microvessels.
• Confirmed the feasibility of using PT microscopy for label-free cell tracking in microcirculation.

Conclusions:

• Photothermal (PT) microscopy is a viable optical tool for real-time, in vivo imaging of unlabeled, motile cells.
• The technique, termed PT flow cytometry, shows promise for studying cellular dynamics in microcirculation.
• Potential applications include diagnostics and fundamental biological research requiring label-free cell analysis.