Scientists create eye tissue using 3D printing

Scientists have found a way to create eye tissue using stem cells and 3D printing as part of a new study that could lead to breakthroughs in the treatment of a range of degenerative eye diseases.

A team of researchers from the National Eye Institute, part of the National Institutes of Health, has printed a combination of cells that form the outer barrier between the blood and the retina, the eye tissue that supports the retina’s light-sensitive photoreceptors.

Their technique provides a theoretically unlimited supply of patient-derived tissue to study degenerative retinal diseases such as age-related macular degeneration and use them to better understand how to treat such diseases.

“We know that AMD starts at the outer blood-brain barrier of the retina,” said Kapil Bharti, Ph.D.

“However, the mechanisms of AMD initiation and progression to advanced dry and wet stages remain poorly understood due to the lack of physiologically meaningful models in humans,” he explained in a statement.

The outer blood-brain barrier of the eye consists of the retinal pigment epithelium, which is separated by the Bruch’s membrane from the choriocapillaries.

Nearly 20 million people in the US alone suffer from some form of age-related macular degeneration. It is the leading cause of vision loss in patients aged 60 and over; it is also the leading cause of irreversible blindness and vision loss worldwide.

“Our collaborative efforts have led to the creation of current models of retinal tissue in degenerative eye diseases. Such tissue models have many potential applications in translational applications, including the development of therapeutics,” said co-author Mark Ferrer, director of the 3D Tissue Bioprinting Laboratory at NIH’s National Center for Advanced Translational Science.

Dr. Bharti and colleagues combined three types of immature choroid cells in a hydrogel: pericytes and endothelial cells, which are key components of capillaries; and fibroblasts, which give tissue structure. They then printed the gel onto a biodegradable scaffold, and within days the cells began to mature into a dense capillary network.

On the ninth day, the scientists seeded retinal pigment epithelial cells on the other side of the scaffold. A little more than a month later, the tissue reached full maturity.

According to the researchers’ analysis and testing, the printed tissue looked and behaved similarly to the natural outer barrier between the blood and the retina.

The scientists have already published their results in the journal Nature Methods.

Christina DENISYUK.

Photo: Shutterstock / Serg Zastavkin