Fabrication of biomimetic corneas featuring epithelial, stromal, and endothelial layers via bioprinting

Abstract

The bioengineering of full-thickness corneal substitutes presents significant challenges, primarily due to the complex stratified structure of the cornea, which consists of the epithelium, stroma, and endothelium, as well as its critical functional requirements, including optical transparency, mechanical stability, and biocompatibility. Herein, we present an integrated fabrication strategy that combines embedded hydrogel bioprinting with subsequent two-dimensional endothelial cell seeding to create biomimetic corneal structures using a gelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA) composite hydrogel. The engineered scaffold successfully recapitulates the native cornea’s trilaminar architecture (epithelium, stroma, and endothelium) and exhibits 30–80% optical transparency across the visible spectrum. The hybrid hydrogel exhibits optimal wettability (a contact angle of approximately 50° and minimal swelling of less than 10%) and controlled degradation kinetics, effectively addressing the limitations of single-component hydrogels. The scaffold maintains structural integrity during suturing and supports robust cellular proliferation and migration. Gene expression analysis revealed the phenotypic orientation of seeded cells toward key corneal lineages, with upregulation of epithelial (Klf4 and Pax6), stromal (Col1a1 and Col4a4), and endothelial (Zeb1 and Foxc1) markers. Overall, the bioprinted GelMA/HAMA biomimetic cornea presents a promising proof of concept for a trilayered tissue-engineered corneal construct.

Keywords

Biomimetic cornea / Hydrogel / Multi-cell types / Three-dimensional bioprinting / Tissue engineering

Funding

This research was supported by the Science and Technology Innovation 2035 Major Project of Ningbo (No. 2024Z212), the Ningbo Natural Science Foundation (No. 2022J121), Zhejiang Provincial Disease Prevention and Control Science and Technology Program (Grant No. 2025JK276) and the Key Laboratory of Polymeric Composite & Functional Materials of the Ministry of Education (No. PCFM-2025A02).

Conflict of Interest

The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.

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