Adhesive Peptide Sequences Regulate Valve Interstitial Cell Adhesion, Phenotype and Extracellular Matrix Deposition

Area of Science:

• Biomaterials Science
• Cell Biology
• Tissue Engineering

Background:

• Knowledge of extracellular matrix (ECM) interactions with valve interstitial cells (VICs) is crucial for understanding valvular diseases and developing functional living valve substitutes.
• Adhesive peptides mimicking the ECM can elucidate adhesion-mediated cell signaling and cellular responses.

Purpose of the Study:

• To investigate the impact of ECM-mimicking peptides on VIC adhesion, phenotype, and ECM synthesis.
• To determine how specific receptor-targeting peptides influence VIC behavior in 2D and 3D hydrogel cultures.

Main Methods:

• Assessed VIC adhesion receptor expression using flow cytometry.
• Incorporated RGDS, DGEA, YIGSR, and VAPG peptides into hydrogels to study their effects on VICs in 2D and 3D cultures.
• Evaluated VIC phenotype markers (smooth muscle α-actin, alkaline phosphatase) and ECM deposition.

Main Results:

• DGEA, YIGSR, and VAPG alone did not induce stable VIC adhesion; combinations with RGDS were used.
• On 2D surfaces, YIGSR and VAPG downregulated myofibroblast markers, while DGEA promoted adhesion, ECM deposition, and inhibited osteogenic markers.
• YIGSR and DGEA together promoted ECM deposition and inhibited both myofibroblastic and osteogenic differentiation.
• In 3D hydrogels, most VICs maintained a quiescent phenotype, with DGEA promoting ECM deposition.

Conclusions:

• Defined peptides targeting specific adhesion receptors can modulate VIC adhesion, phenotype, and ECM synthesis.
• Peptide presentation and dimensionality (2D vs. 3D) significantly influence VIC responses.
• This approach offers potential for engineering functional valvular tissues.