A three-dimensional model of a blinking human eye made with human cells is described in a paper published online this week in Nature Medicine.
Human organs have complex multicellular structures that function as gatekeepers to the external environment and maintain homeostasis. Despite advances in our understanding of these tissue barriers, emulating their multifaceted features remains a major challenge.
To address this issue, Dongeun Huh and colleagues developed a 3D model of the ocular surface that mimics that geometry and cellular composition of the outermost layers of the human eye. The authors grew tissue cells derived from the cornea and conjunctiva in an air - liquid interface to create the surface of the eye. The surface was then cultured within a platform that exposed it to tear fluids and an artificial hydrogel eyelid that mimicked spontaneous blinking. Using this platform, the authors successfully modeled evaporative dry-eye disease and tested the therapeutic effects of an investigational drug.
The authors conclude that although it is possible that this new cell-based system could eventually replace existing animal models, further investigation is required to demonstrate its ability to advance future drug discovery and testing. Additional work will also be required to incorporate other cell types and functions into these models, such as vasculature, immune cells, and nerve innervation.