Collagen networks within 3D PEG hydrogels support valvular interstitial cell matrix mineralization

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Cell Biology

Background:

• Valvular interstitial cells (VICs) are crucial in heart valve function and disease.
• Understanding the role of the microenvironment in VIC osteogenesis is vital for treating valvular heart disease.
• Current 3D culture models lack the necessary biomimicry to fully recapitulate in vivo conditions.

Purpose of the Study:

• To design and utilize enzymatically degradable hydrogels for 3D culture of VICs.
• To investigate the impact of matrix composition on VIC osteogenic differentiation and matrix mineralization.
• To establish a platform for screening therapeutics targeting valvular mineralization.

Main Methods:

• Porcine VICs were encapsulated in poly(ethylene glycol) hydrogels with MMP-degradable crosslinkers.
• Hydrogels were formed via thiol-ene photoclick reaction, with or without collagen type I.
• Osteogenic response was assessed via gene expression (RUNX2, OCN, VIM), Von Kossa staining, calcium assays, and optical density.

Main Results:

• VICs cultured in hydrogels showed osteogenic differentiation markers.
• Supplementation with calcium chloride upregulated osteocalcin (OCN) and induced mineralization by day 12.
• The hydrogel platform enabled high-throughput screening of drug therapeutics for anti-mineralization efficacy.

Conclusions:

• Matrix composition plays a critical role in promoting osteogenic properties and matrix mineralization of VICs.
• Enzymatically degradable hydrogels provide a valuable platform for studying VIC behavior and developing therapeutic strategies.
• This research offers insights into the mechanisms of mineralization in diseased valve tissue.