Injectable ultrathin porous membranes harnessing shape memory polymers for retinal tissue engineering

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Ophthalmology

Background:

• Age-related macular degeneration (AMD) causes vision loss through retinal cell degeneration.
• Current AMD treatments slow progression but do not restore vision.
• Tissue engineering offers potential for retinal regeneration.

Purpose of the Study:

• To engineer ultrathin, nanoporous membrane scaffolds that mimic Bruch's membrane (BrM).
• To evaluate these scaffolds for retinal pigment epithelial (RPE) cell transplantation in AMD treatment.
• To assess scaffold properties for biocompatibility, RPE cell support, and minimally invasive delivery.

Main Methods:

• Fabrication of nanoporous scaffolds using vapor-induced phase separation from PLCL and PLGA blends.
• Characterization of scaffold topography, biocompatibility, and shape-memory properties.
• In vitro evaluation of RPE cell growth and tight junction formation on scaffolds.
• Ex vivo assessment of scaffold self-expansion and catheter-based delivery.

Main Results:

• Scaffolds exhibited a nanoporous topography supporting RPE monolayer formation with intact tight junctions.
• Shape-memory properties allowed scaffolds to self-expand at body temperature (37 °C).
• Cell-laden membranes demonstrated shape recovery and successful delivery via catheter in an ex vivo model.

Conclusions:

• The developed nanoporous scaffolds show promise for retinal tissue engineering.
• These scaffolds facilitate RPE cell transplantation for potential AMD treatment.
• The technology offers a new avenue for advanced treatments of retinal degenerative diseases.