Long-term Observation After Transplantation of Cultured Human Corneal Endothelial Cells for Corneal Endothelial Dysfunction

Background At present, corneal transplantation is still the only way to treat serious corneal diseases caused by corneal endothelial dysfunction. However, the shortage of donor cornea tissues and human corneal endothelial cells (HCECs) remains a worldwide challenge. We cultivated HCECs by the use of a conditioned medium from orbital adipose-derived stem cells (OASC-CM) in vitro. Then the HCECs were used to treat animal corneal endothelial dysfunction models via cell transplantation. The initial effect was gratifying. The purpose of this study was to conduct a long-term observation and evaluation after cell transplantation. Methods First, orbital adipose-derived stem cells (OASCs) were isolated to prepare conditioned medium (CM). Then HCECs were cultivated and expanded by the usage of CM (CM-HCECs). Related CEC markers were analyzed by immunofluorescence. Cells proliferation ability was also tested. CM-HCECs were then transplanted into monkey corneal endothelial dysfunction models by cell injection. We carried out a 24-month postoperative preclinical observation and verified the long-term effect by histological examination and transcriptome sequencing. Results CM-HCECs expressed HCEC related markers and maintained polygonal cell morphology after several passages. During 24 months of cell transplantation into the monkey's anterior chamber, the cornea thickness and transparency kept healthy status, and the corneal endothelial cell density remained in the normal range. Gene sequencing showed that the gene expression pattern of CM-HCECs was similar to that of transplanted cells and HCECs. Conclusions The proliferation and repair ability of HCECs were significantly improved due to the effect of OASC-CM. The result of this study confirmed long-term therapeutic efficacy of CM-HCECs in vivo. Our research provided an extensive cell source and a promising prospect for regenerative medicine and cell-based therapy.

Corneal Edema with Anterior Uveitis after Exposure to the Sap of Euphorbia trigona: A Case Report

Although a few cases of dermatitis or keratitis caused by exposure to the sap of <i>Euphorbia trigona</i> have been reported, we present a rare case of transient corneal endothelial dysfunction following exposure to the sap, resulting in corneal edema. A woman in her 70s complained of reduced vision, redness, and teariness in her left eye 2 days after exposure to the sap of <i>E</i>. <i>trigona</i> at home. Upon examination, hyperemia, serious corneal edema, and anterior uveitis with hypopyon were observed in her left eye, without corneal epithelial defects or keratic precipitates. The best-corrected visual acuity (BCVA) was 2.0 (logarithm of the minimum angle of resolution), and the measured central corneal thickness (CCT) was 812 µm. The patient was treated with topical instillation of 1.5% levofloxacin and 0.1% dexamethasone to reduce intraocular inflammation and corneal edema. Three weeks later, the BCVA reached 0, the CCT was 519 μm, and the corneal endothelial cell density was 3,233 cells/mm². Six months after the injury, the patient had good visual acuity, and the cornea was completely transparent. No recurrence of corneal edema or anterior uveitis was observed. Exposure to the sap of <i>E</i>. <i>trigona</i> can lead to severe corneal edema with anterior uveitis, impairing visual acuity. Taking precautions to prevent the exposure of the eye to the sap of this plant is crucial.

New Horizons in the Treatment of Corneal Endothelial Dysfunction

The treatment of corneal endothelial dysfunction has experienced a revolutionary change in the past decades with the emergence of endothelial keratoplasty techniques: descemet stripping automated endothelial keratoplasty (DSAEK) and descemet membrane endothelial keratoplasty (DMEK). Recently, new treatments such as cultivated endothelial cell therapy, Rho-kinase inhibitors (ROCK inhibitors), bioengineered grafts, and gene therapy have been described. These techniques represent new lines of treatment for endothelial dysfunction. Their advantages are to help address the shortage of quality endothelial tissue, decrease the complications associated with tissue rejection, and reduce the burden of postoperative care following transplantation. Although further randomized clinical trials are required to validate these findings and prove the long-term efficacy of the treatments, the positive outcomes in preliminary clinical studies are a stepping stone to a promising future. Our aim is to review the latest available alternatives and advancements to endothelial corneal transplant.

Therapeutic potential of Rho-associated kinase inhibitor Y27632 in corneal endothelial dysfunction: an in vitro and in vivo study

AIM: To investigate the effects of a selective inhibitor of Rho-associated kinase (ROCK), Y-27632, on inbred Wuzhishan porcine corneal endothelial cells (PCECs) in vitro and in vivo studies. METHODS: Primary PCECs were trypsinized from Wuzhishan miniature porcine corneal tissues. The optimal concentration of Y-27632 on PCECs was determined through MTT and 5-ethynyl-2’-deoxyuridine (EdU)-labeling assays. Seven New Zealand rabbits were used as a corneal endothelial dysfunction model, and a PCECs suspension supplemented with Y-27632 was injected into the anterior chamber of the rabbits. The progression of rabbit corneal opacity and edema were observed by slit lamp examination. The rabbits were sacrificed, and rabbit globes were enucleated for trypan blue-alizarin red staining, hematoxylin-eosin staining, and immunofluorescence analysis. RESULTS: Administration of 100 μmol/L Y-27632 facilitated PCECs’ proliferation obviously. The rabbit corneas injected with PCECs suspension and 100 μmol/L Y-27632 were restored to transparency significantly after 14d. CONCLUSION: The 100 μmol/L Y-27632 treatment improves PCECs’ proliferation significantly. And our results suggest that Y-27632 and PCECs can be used to treat corneal endothelial dysfunction.

Long-Term Observation and Sequencing Analysis of SKPs-Derived Corneal Endothelial Cell-Like Cells for Treating Corneal Endothelial Dysfunction

Corneal endothelial dysfunction is a principal cause of visual deficiency. Corneal transplantation is the most effective treatment for corneal endothelial dysfunction. However, a severe shortage of available donor corneas or human corneal endothelial cells (HCECs) remains a global challenge. Previously, we acquired corneal endothelial cell-like cells (CEC-like cells) derived from human skin-derived precursors (SKPs). CEC-like cells were injected into rabbit and monkey corneal endothelial dysfunction models and exerted excellent therapeutic effect. In this study, we prolonged the clinical observation in the monkey experiment for 2 years. Polymerase chain reaction (PCR) and DNA sequencing were carried out to confirm the existence of CEC-like cells. Histological examinations were carried out to show the corneal morphology. Further transcriptome sequencing was also carried out on HCEC, CEC-like cells before transplantation and after transplantation. We found that the monkeys cornea remained transparent and normal thickness. The total endothelial cell density decreased gradually, but tended to be stable and remained in a normal range during 2-year observation. The CEC-like cells persist during observation and could adapt to the microenvironment after transplantation. The gene expression pattern of CEC-like cells was similar to HCEC and changed slightly after transplantation. In conclusion, this study presented a brand-new insight into CEC-like cells and further provided a promising prospect of cell-based therapy for corneal endothelial dysfunction. The renewable cell source, novel derivation method and simple treatment strategy may be clinically applied in regenerative medicine in the future.