Optical Microscopy and the Extracellular Matrix Structure: A Review

Area of Science:

• Biomedical Engineering
• Cell Biology
• Microscopy

Background:

• Biological tissues comprise cells and a significant extracellular matrix (ECM).
• The ECM provides structural and functional integrity to tissues and organs.
• Understanding cell-ECM interactions is vital for tissue formation, remodeling, and fibrotic diseases.

Purpose of the Study:

• To review optical imaging microscopy modalities for characterizing ECM components.
• To provide examples of applications for various microscopy techniques in ECM research.

Main Methods:

• Widefield fluorescence microscopy
• Total internal reflection fluorescence microscopy
• Laser scanning confocal microscopy
• Multipoint/slit confocal microscopy
• Two-photon excited fluorescence (TPEF)
• Second and third harmonic generation (SHG, THG)
• Coherent anti-Stokes Raman scattering (CARS)
• Fluorescence lifetime imaging microscopy (FLIM)
• Structured illumination microscopy (SIM)
• Stimulated emission depletion microscopy (STED)
• Ground-state depletion microscopy (GSD)
• Photoactivated localization microscopy (PALM/fPALM)

Main Results:

• The review details a wide array of optical microscopy techniques applicable to ECM visualization.
• Each technique offers distinct advantages and limitations for studying ECM structure and dynamics.
• Examples of applications demonstrate the utility of these methods in understanding tissue microenvironments.

Conclusions:

• Optical microscopy is essential for visualizing ECM components and their role in tissue health and disease.
• The selection of appropriate microscopy techniques is critical for successful ECM characterization.
• Advancements in microscopy enable deeper insights into cell-ECM interactions and fibrotic processes.