Characterization of valvular interstitial cell function in three dimensional matrix metalloproteinase degradable PEG...

Area of Science:

• Biomaterials Science
• Cell Biology
• Tissue Engineering

Background:

• Valvular interstitial cells (VICs) are crucial for heart valve structure and function.
• Traditional 2D cell culture lacks the complexity to fully represent VIC behavior.
• A 3D environment is needed to accurately study VICs for valve repair and disease research.

Purpose of the Study:

• To develop and validate a 3D matrix metalloproteinase (MMP)-degradable poly(ethylene glycol) (PEG) hydrogel system.
• To characterize valvular interstitial cell (VIC) behavior, including morphology, proliferation, migration, and differentiation, within this 3D system.
• To assess the impact of matrix properties (RGD concentration and hydrogel density) and growth factors (TGF-beta1) on VICs.

Main Methods:

• Encapsulation of VICs within MMP-degradable PEG hydrogels.
• Incorporation of RGD peptides to promote integrin binding.
• Varying hydrogel matrix density to influence cell morphology and process extension.
• Stimulation with transforming growth factor-beta1 (TGF-beta1) to induce myofibroblast differentiation.
• Real-time cell microscopy, gene expression analysis (mRNA), and protein level analysis (alphaSMA, collagen-1).

Main Results:

• VICs exhibited spread morphology, proliferation, and migration within the 3D hydrogel.
• Increased RGD concentration enhanced VIC process extension and integrin alpha(v)beta(3) binding.
• Decreased hydrogel density promoted VIC morphology and process extension.
• TGF-beta1 induced VIC differentiation into myofibroblasts, characterized by increased alphaSMA and collagen-1 expression, sustained for 2 weeks.
• The hydrogel system demonstrated biological activity and flexibility for VIC characterization.

Conclusions:

• The developed MMP-degradable PEG hydrogel system is a valuable tool for 3D VIC characterization.
• This system supports key VIC functions and responses to biological cues, crucial for tissue engineering and pathobiology.
• The findings highlight the system's utility for advancing research in heart valve disease and regenerative medicine.