Development of topical bioactive formulations capable of overcoming the low bioavailability of conventional eye drops is critically important for efficient management of ocular chemical burns. Herein, a nanomedicine strategy is presented to harness the surface roughness‐controlled ceria nanocages (SRCNs) and poly(l‐histidine) surface coatings for triggering multiple bioactive roles of intrinsically therapeutic nanocarriers and promoting transport across corneal epithelial barriers as well as achieving on‐demand release of dual drugs [acetylcholine chloride (ACh) and SB431542] at the lesion site. Specifically, the high surface roughness helps improve cellular uptake and therapeutic activity of SRCNs while exerting a negligible impact on good ocular biocompatibility of the nanomaterials. Moreover, the high poly(l‐histidine) coating amount can endow the SRCNs with an ≈24‐fold enhancement in corneal penetration and an effective smart release of ACh and SB431542 in response to endogenous pH changes caused by tissue injury/inflammation. In a rat model of alkali burn, topical single‐dose nanoformulation can efficaciously reduce corneal wound areas (19‐fold improvement as compared to a marketed eye drops), attenuate ≈93% abnormal blood vessels, and restore corneal transparency to almost normal at 4 days post‐administration, suggesting great promise for designing multifunctional metallic nanotherapeutics for ocular pharmacology and tissue regenerative medicine.

Background. This study was performed to investigate whether transplantation of bioengineered human corneal endothelial cell (HCEC) sheet grafts into corneas denuded of endothelium could restore corneal function and clarity in a rabbit model. Methods. After being labeled with PKH26 fluorescent dye, the adult HCECs derived from eye bank corneas were cultivated on the thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm)-grafted surfaces for 3 weeks at 37°C, and were harvested as transplantable cell sheets after incubation for 45 min at 20°C. Attached by gelatin hydrogel discs, the bioengineered cell monolayers were transplanted to rabbit corneas denuded of endothelium (HCEC sheet group). Traumatized rabbit corneas were served as controls. Postsurgical corneas underwent clinical observations and histological examinations for 6 months. Results. By transmission electron microscopy and Western blot analysis of zonula occludens-1 and Na⁺,K⁺-adenosine triphosphatase proteins, the structure and function of HCEC sheets resembled those of native corneal endothelium. After endothelial cells were removed, corneas of each group turned severe edematous and opaque. In the HCEC sheet groups, corneal clarity was gradually restored and corneal thickness was significantly less than that in the control groups (P<0.05). The attached PKH26-positive HCECs spread on rabbit Descemet’s membrane after receiving cell sheet grafts. Intraocular delivery of HCEC sheets by means of a minimally invasive technique (i.e., small-incision surgery using biodegradable hydrogels) demonstrated long-term graft integration with damaged corneas. Conclusions. These results indicate that using cultured HCECs and functional biomaterials, PNIPAAm and gelatin, an effective cell sheet-based therapy can be developed for the treatment of corneal endothelium deficiency.