Multiphoton Imaging of Maturation in Tissue Engineering.

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Cardiovascular Research

Background:

• Tissue-engineered (TE) implants offer personalized cardiovascular disease treatment.
• Current methods lack longitudinal, subcellular assessment of TE construct development.
• Histological slicing is destructive and prevents longitudinal studies.

Purpose of the Study:

• Establish a generalized labeling and 3D imaging protocol for TE constructs.
• Enable quantified, longitudinal assessment of TE tissue maturation without slicing.
• Analyze intracellular matrix (ICM) and extracellular matrix (ECM) development.

Main Methods:

• Developed a whole-mount labeling and multiphoton laser scanning microscopy (MPLSM) protocol.
• Imaged TE patches over 21 days of conditioning in 3D.
• Quantified cell coverage, ICM, and ECM volume fractions using image analysis.

Main Results:

• Achieved high-quality 3D imaging of intact TE constructs.
• Demonstrated increased collagen and alpha-smooth muscle actin (α-SMA) volume fractions with maturation.
• Observed developing, interconnected ICM and ECM networks.

Conclusions:

• The developed MPLSM protocol allows non-destructive, quantitative assessment of TE construct maturation.
• This method supports personalized TE therapy development for cardiovascular diseases.
• Future work includes integrating MPLSM into bioreactors for dynamic monitoring.