Stem Cell Therapy for Corneal Regeneration Medicine and Contemporary Nanomedicine for Corneal Disorders

Abstract

The ocular surface is the outermost part of the visual system that faces many extrinsic or intrinsic threats, such as chemical burn, infectious pathogens, thermal injury, Stevens-Johnson syndrome, ocular pemphegoid, and other autoimmune diseases. The cornea plays an important role in conducting light into the eyes and protecting intraocular structures. Several ocular surface diseases will lead to the neovascularization or conjunctivalization of corneal epithelium, leaving opacified optical media. It is believed that some corneal limbal cells may present stem cell-like properties and are capable of regenerating corneal epithelium. Therefore, cultivation of limbal cells and reconstruction of the ocular surface with these limbal cell grafts have attracted tremendous interest in the past few years. Currently, stem cells are found to potentiate regenerative medicine by their capability of differentiation into multiple lineage cells. Among these, the most common cell sources for clinical use are embryonic, adult, and induced stem cells. Different stem cells have varied specific advantages and limitations for in vivo and in vitro expansion. Other than ocular surface diseases, culture and transplantation of corneal endothelial cells is another major issue for corneal decompensation and awaits further studies to find out comprehensive solutions dealing with nonregenerative corneal endothelium. Recently, studies of in vitro endothelium culture and r-associated kinase (ROCK) inhibitor have gained encouraging results. Some clinical trials have already been finished and achieved remarkable vision recovery. Finally, nanotechnology has shown great improvement in ocular drug delivery systems during the past two decades. Strategies to reconstruct the ocular surface could combine with nanoparticles to facilitate wound healing, drug delivery, and even neovascularization inhibition. In this review article, we summarized the major advances of corneal limbal stem cells, limbal stem cell deficiency, corneal endothelial cell culture/transplantation, and application of nanotechnology on ocular surface reconstruction. We also illustrated potential applications of current knowledge for the future treatment of ocular surface diseases.

Nanoparticles in wound healing from hope to promise from promise to routine

“…diabetic retinopathy) and reconstruct traumadistorted surfaces (e.g. ocular reconstruction) (149). Another group injected human MSCs with quantum dot NPs and seeded them onto a fibrin suture.…”

The molecular mechanisms of action of PPAR-γ agonists in the treatment of corneal alkali burns?(Review)

“…Stem cells potentiate regeneration due to their ability to differentiate into multiple cell lineages. The most common sources of stem cells for clinical use are embryonic, adult and induced ( 6 ). Surface transplantation and subsequent keratoplasty can result in good visual function following ocular injury ( 7 ).…”

Primary Mechanisms of Thymosin β4 Repair Activity in Dry Eye Disorders and Other Tissue Injuries

“…77 The corneal epithelium is thought to be regenerated from stem cells in the limbus which are activated with injury. 78 Some studies have shown successful stem cell transplants for ocular repair, but these studies are at an early stage. 78 The concerns with stem cell transplantation generally include the limited number of cells requiring expansion in vitro, teratoma formation, and immune reaction, lifelong immunosuppression.…”

“…78 Some studies have shown successful stem cell transplants for ocular repair, but these studies are at an early stage. 78 The concerns with stem cell transplantation generally include the limited number of cells requiring expansion in vitro, teratoma formation, and immune reaction, lifelong immunosuppression. The role of stem cells in Tb4-mediated ocular repair has not yet been investigated, but it can be assumed that these cells play an important role.…”