Mimicking the development of the whole eye with human iPS cells

While studies in the past only described techniques to generate the posterior portion of the eye (the retina, the pigmented epithelium of the retina, etc.), this group's study described a technique capable of generating both the anterior portion (the cornea, lens, etc.) and the posterior portion of the eye (the retina, the pigmented epithelium of the retina, etc.) at the same time, a world first.

For treatment of serious corneal epithelium diseases that lead to blindness, corneal transplantation using donor cornea has been conducted, but this approach is hampered by rejection and a shortage of donors.

In the past, there were no techniques to induce human iPS cells to differentiate into corneal epithelial cells and isolate those cells to create functional corneal epithelium.

The culture system developed in this study can use human iPS cells to generate a 2-dimensional structure, a self-formed ectodermal autonomous multi-zone (SEAM), consisting of 4 concentric zones of cells.

Major groups of cells that comprise the eye during development (e.g. corneal epithelium, the retina, and the epithelium of the lens) are produced at specific locations in the SEAM.

This group isolated corneal epithelial progenitor cells from the 3rd zone of the SEAM, successfully generating functional corneal epithelium.

This group also verified therapeutic effects of corneal epithelium produced from human iPS cells through the transplantation onto animal models.

Results of this study should greatly help to facilitate reconstruction of the corneal epithelium with iPS cells in humans. Furthermore, the SEAM has also the potential to facilitate the development of techniques to reconstruct the cornea as well as other portions of the eye.

This research was featured in the electronic version of Nature.