Conquering intractable blindness with an artificial retina

Retinal vein occlusion (RVO) is one of the leading causes of vision loss worldwide, often triggered by chronic diseases such as hypertension and diabetes. Similar to a blocked water pipe causing backflow and pressure buildup, an occluded retinal vein leads to edema, inflammation, and neovascularization, ultimately resulting in irreversible blindness. Despite the availability of anti-VEGF injections and laser therapy, there is still no effective treatment that fully restores damaged retinal tissues, primarily due to the lack of physiologically relevant disease models.

A joint research team led by Professor Dong-Woo Cho of the Department of Mechanical Engineering at POSTECH, Professor Jae Yon Won of the Department of Ophthalmology and Visual Science at Eunpyeong St. Mary’s Hospital, and Professor Joeng Ju Kim of the Department of Bioscience and Biotechnology at Hankuk University of Foreign Studies (HUFS) has successfully developed an RVO disease model based on a 3D-bioprinted retina-on-a-chip platform that closely recapitulates the pathological microenvironment of retinal vein occlusion. This breakthrough study was published in Advanced Composites and Hybrid Materials, a top-tier international journal in materials and nanoengineering.

The team utilized an integrated 3D bioprinting system combined with a hybrid retinal decellularized extracellular matrix (RdECM) bioink to fabricate a retina-on-a-chip featuring both vascular and neural layers. By fabricating vascular occlusion within the chip, the model successfully reproduced hallmark RVO pathologies—such as inflammation, barrier dysfunction, and aberrant angiogenesis—allowing real-time observation of cellular interactions between endothelial and retinal cells. The RVO model exhibited vascular leakage and edema responses comparable to those observed in clinical RVO patients.

Furthermore, in the RVO model, the researchers observed that the vascular endothelium lost its selective permeability, mirroring the pathological changes seen in actual patients. When conventional anti-inflammatory or anti-angiogenic drugs were administered, the model exhibited drug responses highly consistent with those observed in clinical RVO cases. Specifically, aspirin effectively suppressed vascular damage, while treatment with dexamethasone and bevacizumab reduced inflammation and abnormal neovascularization. These findings demonstrate that the developed platform can accurately reproduce pharmacological reactions in vitro, validating its potential as a preclinical drug evaluation and patient-specific therapeutic screening system.

The team envisions that this RVO model will serve as a powerful preclinical platform for investigating RVO pathogenesis, evaluating novel therapeutics, and reducing reliance on animal experiments. The approach also demonstrates the potential of organ-specific dECM (Decellularized Extracellular Matrix) bioinks to reproduce complex human tissue microenvironments for personalized medicine.

This research was supported by the Alchemist Project of the Ministry of Trade, Industry and Energy, the National Program for Regenerative Medicine, the Young Researcher Program of the National Research Foundation of Korea, and the Research Fund of Hankuk University of Foreign Studies.