Bioengineered corneal endothelial graft using photodegradable device to induce graft-host integration - PROJECT SUMMARY
Although the bioengineered human corneal endothelial cell (hCEC) monolayer graft have shown vision
recovery in animal models, the hCEC monolayer do not integrate with the host cornea due to suboptimal and
non-tunable degradation of the hCEC-carrier biomaterial in the anterior chamber, which provide mechanical
support to the monolayer. Thus, whether the transplanted hCEC monolayer will integrate with the host cornea
following the complete degradation of the hCEC-carrier biomaterial and remain functional thereafter is
unknown. To validate the bioengineered hCEC monolayers, there is a clear need to develop a biomaterial that
has tunable-degradation rate in-vivo to evaluate the engraftment of the hCECs, and is mechanically strong so
that the biomaterial-film/hCEC-monolayer construct does not break during the transplantation. The previous
work of the team has established that the extracellular-topography cues can significantly modulate hCEC
responses. The preliminary work of the team has developed photodegradable hydrogel (pdGel), which can be
degraded in a tunable manner after transplantation, within hours to weeks, using tissue-penetrative light.
Accordingly, the objective of this proposal is to develop a nano-topography pdGel-hCEC monolayer graft,
evaluate monolayer integration with host cornea by tuning the in-vivo degradation rate of the pdGel, and
validate the hCEC-monolayer function in-vivo. It is hypothesized that the nano-patterned pdGel will enable the
growth of hCECs as a confluent monolayer, improve the hCEC monolayer function and stability by inducing the
deposition of native-like extracellular matrix (ECM), and the tunable photodegradation of the carrier will
improve the engraftment of the hCEC monolayer. The rationale for this project is the evaluation of the
engraftment of hCEC monolayer with the cornea and the function thereafter will validate the use of
bioengineered hCEC grafts for potential treatment of multiple corneal patients with one donor. Towards the
overall objective, in the first aim, the hCEC monolayer growth on the pdGel, photodegradation kinetics, the
biocompatibility of the degradation products, and the engraftment of the monolayer will be evaluated in-vitro
and ex–vivo. In the second aim, using a high-throughput topography platform, the effect of 253 unique pdGel
topographies will be evaluated on the hCEC monolayer functions to identify the optimum graft design. In the
third aim, the photodegradation rate will be tuned in-vivo using light exposure to evaluate its effect on the
hCEC engraftment. The proposed research is expected to be significant because it will validate the
bioengineered hCEC-monolayer graft technology using a new photodegradable biomaterial, and it will develop
new biomaterial and nano-topography platform that will have significant applications beyond ocular tissue
engineering. The proposed research is innovative because it, (1) uses two-photon lithography approach to
develop an innovative, high throughput nano-topography platform, and (2) leverages the photo-decomposition
liability of the cyanine dye to develop an innovative photodegradable hydrogel for hCEC engraftment.
