Sterilized, freeze-dried amniotic membrane: a useful substrate for ocular surface reconstruction

Area of Science:

• Ophthalmology
• Biomaterials Science
• Tissue Engineering

Background:

• Ocular surface reconstruction often requires corneal epithelial cell transplantation.
• Autologous corneal epithelial cells cultured on amniotic membrane (AM) show promise for these procedures.
• Preservation methods for AM are crucial for maintaining its biological properties.

Purpose of the Study:

• To assess the feasibility of using sterilized, freeze-dried amniotic membrane (FD-AM) as a substrate for cultivating autologous corneal epithelial cells.
• To evaluate FD-AM's suitability for ocular surface reconstruction.

Main Methods:

• Human AM was processed by removing epithelial cells, freeze-drying, vacuum packing, and gamma-irradiation sterilization.
• FD-AM properties were analyzed using stretch stress tests, immunohistochemistry, and electron microscopy.
• Autologous corneal epithelial cells were cultured on FD-AM and transplanted onto surgically injured rabbit corneas.

Main Results:

• Sterilized FD-AM exhibited comparable physical properties to cryopreserved AM.
• Freeze-drying and irradiation did not significantly alter the biological or morphological characteristics of AM.
• Corneal epithelial cells cultured on FD-AM formed well-differentiated, stratified layers.
• Rabbit corneas grafted with cells on FD-AM showed complete epithelialization and clarity within 10 days.

Conclusions:

• Sterilized, freeze-dried amniotic membrane retains essential physical, biological, and morphological features.
• FD-AM serves as a promising biomaterial for ocular surface reconstruction procedures.
• This method offers a stable and effective substrate for corneal epithelial cell cultivation.