Cholesterol-modified superporous poly(2-hydroxyethyl methacrylate) scaffolds for tissue engineering

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Poly(2-hydroxyethyl methacrylate) (PHEMA) is a widely used biomaterial, but its surface properties often limit cell interactions.
• Modifications are needed to enhance cell attachment, spreading, and proliferation for effective tissue regeneration.
• Incorporating cholesterol and laminin can improve the bioactivity of PHEMA scaffolds.

Purpose of the Study:

• To develop and characterize cholesterol-modified superporous PHEMA scaffolds for improved cell-surface interaction.
• To immobilize laminin onto these scaffolds to further promote cell adhesion and growth.
• To evaluate the attachment, viability, and morphology of mesenchymal stem cells (MSCs) on modified and unmodified PHEMA hydrogels.

Main Methods:

• Bulk radical copolymerization of 2-hydroxyethyl methacrylate (HEMA), cholesterol methacrylate (CHLMA), and ethylene dimethacrylate (EDMA) to create superporous scaffolds.
• Introduction of carboxyl groups via copolymerization with 2-[(methoxycarbonyl)methoxy]ethyl methacrylate (MCMEMA) for subsequent laminin immobilization.
• Hydrolysis of MCMEMA to [2-(methacryloyloxy)ethoxy]acetic acid (MOEAA) followed by laminin attachment using carbodiimide chemistry.
• Assessment of MSC behavior on various PHEMA-based hydrogels (nonporous, superporous, modified, unmodified).

Main Results:

• Cholesterol-modified P(HEMA-CHLMA) and laminin-modified LN-P(HEMA-CHLMA) hydrogels significantly enhanced MSC spreading and proliferation compared to neat PHEMA.
• Neat PHEMA and LN-PHEMA facilitated MSC attachment but did not support sustained spreading or proliferation, with decreased cell viability over time.
• Superporous structures were successfully created, offering potential for enhanced nutrient and waste exchange.

Conclusions:

• Cholesterol modification of PHEMA hydrogels is crucial for promoting MSC spreading and proliferation.
• Superporous, cholesterol- and laminin-modified PHEMA scaffolds offer a promising platform for regenerative medicine.
• These biomaterials demonstrate superior cell-material interactions compared to conventional PHEMA.