Non-invasive multiphoton imaging of extracellular matrix structures

Area of Science:

• Biomedical Optics
• Cellular and Tissue Imaging
• Biomaterials Science

Background:

• Multiphoton microscopy offers artifact-free, nondestructive evaluation of deep-tissue structures.
• Second harmonic generation (SHG) visualizes fibrillar collagen and extracellular matrix (ECM) with submicron resolution.
• Current methods often require tissue processing, limiting in situ and in vivo applications.

Purpose of the Study:

• To review the applications of multiphoton-induced autofluorescence and SHG microscopy.
• To highlight the identification of collagen and elastic fiber orientation in various tissue types.
• To demonstrate the quantification of ECM damage using SHG signal profiling.

Main Methods:

• Utilizing multiphoton-induced autofluorescence for cellular and ECM visualization.
• Employing second harmonic generation (SHG) microscopy for non-linear optical imaging of fibrillar structures.
• Applying SHG signal profiling to quantify ECM damage in diverse tissues.

Main Results:

• Successfully identified collagen and elastic fiber orientation in native, engineered, processed, healthy, and diseased tissues.
• Quantified ECM damage in cardiovascular, exocrine tissues, and cartilage using SHG.
• Demonstrated the capability for high-resolution in situ imaging of ECM and cellular structures.

Conclusions:

• Multiphoton microscopy and SHG are powerful tools for in situ ECM evaluation.
• These techniques allow for artifact-free visualization and quantification of tissue structures and damage.
• Future applications include high-resolution in vivo imaging of cells and ECM in living tissues.