Persistent Corneal Epithelial Defects Research Articles

BMSC-derived exosomes attenuate persistent corneal epithelial injury by affecting retinal neural-like cells

Persistent corneal epithelial defect (PED) is a challenge to human which is difficultly cured, normally requiring long-term follow-up. Herein, this study explored the potential role of bone marrow mesenchymal stem cell-derived exosomes (BMSC-exos) in persistent corneal epithelial injury and the underlying mechanism. After characterization of BMSC-exos, RGC-5 cell viability was determined and surface markers of BMSCs were analyzed. Additionally, RT-qPCR and Western blot measured miR-150-5p, Brn3, Islet-1, and PCNA expression. Dual luciferase assays were conducted to evaluate the targeting relationship between long non-coding Ribonucleic Acid (lncRNA) MIAT and miR-150-5p. Presented in ellipsoidal or cup shape, BMSC-exos were positive to BMSC-specific markers CD29 and CD90, and cell surface markers CD9 and CD63 were detected on exosomes. Importantly, treatment with BMSC-exos significantly promoted proliferation of retinal ganglion cells (RGCs) and hindered cell differentiation. Interestingly, down-regulating lncRNA MIAT exerted the same effect as BMSC-exos, increasing cell viability and decreasing the expression of differentiation-related proteins Brn3 and ISL1. Bioinformatics software predicted miR-150-5P as target of lncRNA MIAT, and the relative luciferase activity of miR-150-5P+MIAT-WT co-transfection group was lower. Conclusively, BMSC-exos can improve PED by targeting and regulating miR-150-5p expression through lncRNA MIAT, which can up-regulate PCNA in RGC-5 cells and down-regulate Brn3 and ISL1.

Topical insulin for refractory persistent corneal epithelial defects

The aim was clinical evaluation of the efficacy of topical insulin eye drops in patients with refractory persistent epithelial defects (PEDs). This prospective non-randomized investigation was conducted to examine the efficacy of insulin eye drops in treating patients with PEDs that did not respond to conventional therapy. A total of twenty-three patients were included in the study, and they were administered insulin eye drops formulated as 1 U/mL, four times a day. The rate of epithelial defect resolution and time to complete corneal re-epithelialization were considered primary outcome measures. The relative prognostic impact of initial wound size and other parameters, including age, sex, smoking, diabetes, and hypertension were also analyzed. The results showed that during follow-up (maximum 50 days), a total of 16 patients (69.6%) achieved improvement. Insulin eye drops significantly reduced the corneal wounding area in 75% of patients with small epithelial defects (5.5 mm2 or less) during 20 days. Only 61% of patients with moderate epithelial defects (5.51–16 mm2) showed a significant recovery in 20–30 days. Also, 71% of patients with a defect size greater than 16 mm2, demonstrated a significant improvement in the rate of corneal epithelial wound healing in about 50 days. In conclusion topical insulin reduces the PED area and accelerates the ocular surface epithelium wound healing.

Topical Insulin Eye Drops: Stability and Safety of Two Compounded Formulations for Treating Persistent Corneal Epithelial Defects.

Compounded insulin eye drops were prepared at 1 IU/mL from commercially available subcutaneous insulin by dilution in saline solution or artificial tears. Physicochemical characterization and in vitro tolerance testing in human and conjunctival cells were followed by a 28-day short-term stability study under various conditions. The formulations were isotonic (280-300 mOsm/L), had a pH close to neutral (7-8), medium surface-tension values (<56 MN/m-1), and low (≈1 mPa·s) and medium (≈5 mPa·s) viscosities (compounded normal saline solution and artificial tear-based preparation, respectively). These values remained stable for 28 days under refrigeration. Microbiological stability was also excellent. Insulin potency remained in the 90-110% range in the compounded formulations containing normal saline solution when stored at 2-8 °C for 28 days, while it decreased in those based on artificial tears. Although both formulations were well tolerated in vitro, the compounded insulin diluted in a normal saline solution exhibited better cell tolerance. Preliminary data in humans showed that insulin in saline solution was an effective and safe treatment for persistent corneal epithelial defects. Compounded insulin eye drops diluted in normal saline solution could, therefore, constitute an emergent therapy for the treatment of persistent corneal epithelial defects.

Blood‐derived trophic factors for the treatment of ocular surface diseases

The use of blood‐derived products (Eye Drop of Human Origin—EDHO; in Italian: Emocomponents for Not Transfusional Use, EUNT) for the treatment of various ocular surface diseases has become increasingly utilized in ophthalmic practice over the years. In particular, they are recommended as a third line option, when conventional tear substitutes, or active drugs, such as corticosteroids or Cyclosporine A, result unsuccessful in controlling either signs and, perhaps most importantly, subjective symptoms of discomfort and pain. The rationale for their use is based on the stimulation of cell proliferation and migration through the supply of metabolically active substances, in particular growth factors, and definitely mimicking the function of natural tears.EDHO have been used for the treatment of various ocular surface diseases, including dry eye, persistent corneal epithelial defect, corneal ulcer, neurotrophic keratitis, ocular surface burn, recurrent corneal erosion and limbal stem cell deficiency. However, the therapeutic potential of these products is still to be fully explored, as randomized clinical trials and internationally recognized harmonized guidelines are still needed to provide better evidence, improve quality of the final products and lead to a more widespread use of these therapies in daily clinical practice. The autologous source is still quite popular, although allogeneic sources appear to be a promising innovation. These might offer the solution of obtaining in advance products tailored for each patient and ocular surface disease, at scalable concentrations based on the severity of the disease and clinical parameters. There remain many unanswered questions regarding what might be considered optimal treatment, sketched as “The 5 Ws (and 2 H) for blood based eye drops”, to quote a review from our group (doi: 10.3390/jcm8091478). This presentation will discuss: 1. who is the patient to be treated, in terms of disease type, severity, and stage?; 2. Why is an EDHO needed, in terms of a target indication?; 3. When is it appropriate to prescribe an EDHO therapy?; 4. Where are EDHO be dispensed, and is a national/regional program a feasible solution to optimize resources?; 5. What is the EDHO of choice, which source and preparation are targeted for a given patient? And further: 1. how is EDHO standardized in terms of processing to ensure an optimal dilution, solvent, dispenser, storage time?; 2. How is EDHO delivered to the ocular surface, in terms of form, dose‐size modulation, length of treatment?An interdisciplinary work with transfusional medicine specialists is imperative to share information and competences, to achieve a better clinical management.

Analysis of long-term outcomes of penetrating keratoplasty for congenital corneal opacity

Objective: To investigate the long-term outcomes of corneal grafts after penetrating keratoplasty(PK) for congenital corneal opacity(CCO) in children aged 0 to 5 years and the related influencing factors. Methods: It was a retrospective series case study. Data of 39 children (55 eyes) who underwent PK surgery due to CCO in the keratology Department of Beijing Tongren Hospital from April 2014 to April 2018 and were followed up for more than 30 months were collected. Among them, there were 17 males (43.6%) and 22 females (56.4%). The age at operation was (16.2±13.3) months, and the follow-up time was (46.4±13.8) months. Clinical data such as basic information, preoperative diagnosis, operation age, operation method and postoperative complications were recorded. The corneal graft transparency was analyzed according to preoperative diagnosis, corneal neovascularization area, age at surgery, monocular or binocular surgery interval, primary surgery type and further surgery, and postoperative complications were observed. Results: At 12 months, 24 months and the last follow-up after PK, 78.2% (43/55), 70.9% (39/55) and 58.2% (32/55) of the affected eyes had clear corneal grafts, respectively.There was no statistical significance between Peters anomaly and sclerocornea (P>0.05), while the extent of neovascularization in the limbus had a significant effect on corneal graft transparency, and graft opacity was more likely to occur in patients with vessel area exceeding 2 quadrants (P<0.05).The highest corneal graft transparency was found in children aged 1 to 3 years 80.8%(21/26) (P<0.05), followed by children younger than 6 months (7/15).The translucency rate of the corneal graft was higher in patients undergoing unilateral surgery than in those undergoing bilateral surgery (P<0.05).Translucency of corneal graft was higher in children with simple surgery than with combined surgery (P<0.05), however, cataract surgery after PK had no significant effect on corneal graft transparency (P>0.05).The postoperative complications mainly included immune rejection in 19 eyes (34.5%), complicated cataract in 13 eyes (23.6%), glaucoma in 7 eyes (13.2%), persistent corneal epithelial defect in 7 eyes (13.2%). Conclusions: After PK in children with CCO, the transparent rate of corneal grafts decreases gradually with time, but the long-term translucency of corneal grafts can still be obtained. The range of corneal neovascularization, age at the time of surgery, whether the surgery was binocular and whether the surgery was combined had an effect on the transparency of corneal graft.

Sustained Inhibition of VEGF and TNF-α Achieves Multi-Ocular Protection and Prevents Formation of Blood Vessels after Severe Ocular Trauma.

This study aimed to develop a clinically feasible and practical therapy for multi-ocular protection following ocular injury by using a thermosensitive drug delivery system (DDS) for sustained delivery of TNF-α and VEGF inhibitors to the eye. A thermosensitive, biodegradable hydrogel DDS (PLGA-PEG-PLGA triblock polymer) loaded with 0.7 mg of adalimumab and 1.4 mg of aflibercept was injected subconjunctivally into Dutch-belted pigmented rabbits after corneal alkali injury. Control rabbits received 2 mg of IgG-loaded DDS or 1.4 mg of aflibercept-loaded DDS. Animals were followed for 3 months and assessed for tolerability and prevention of corneal neovascularization (NV), improvement of corneal re-epithelialization, inhibition of retinal ganglion cell (RGC) and optic nerve axon loss, and inhibition of immune cell infiltration into the cornea. Drug-release kinetics was assessed in vivo using an aqueous humor protein analysis. A single subconjunctival administration of dual anti-TNF-α/anti-VEGF DDS achieved a sustained 3-month delivery of antibodies to the anterior chamber, iris, ciliary body, and retina. Administration after corneal alkali burn suppressed CD45+ immune cell infiltration into the cornea, completely inhibited cornea NV for 3 months, accelerated corneal re-epithelialization and wound healing, and prevented RGC and optic nerve axon loss at 3 months. In contrast, anti-VEGF alone or IgG DDS treatment led to persistent corneal epithelial defect (combined: <1%; anti-VEGF: 15%; IgG: 10%, of cornea area), increased infiltration of CD45+ immune cells into the cornea (combined: 28 ± 20; anti-VEGF: 730 ± 178; anti-IgG: 360 ± 186, cells/section), and significant loss of RGCs (combined: 2.7%; anti-VEGF: 63%; IgG: 45%) and optic nerve axons at 3 months. The aqueous humor protein analysis showed first-order release kinetics without adverse effects at the injection site. Concomitant inhibition of TNF-α and VEGF prevents corneal neovascularization and ameliorates subsequent irreversible damage to the retina and optic nerve after severe ocular injury. A single subconjunctival administration of this therapy, using a biodegradable, slow-release thermosensitive DDS, achieved the sustained elution of therapeutic levels of antibodies to all ocular tissues for 3 months. This therapeutic approach has the potential to dramatically improve the outcomes of severe ocular injuries in patients and improve the therapeutic outcomes in patients with retinal vascular diseases.

Comparison of the Effect of Autologous Serum on Therapy Resistant Corneal Erosions and Ulcers on the Corneal Graft vs. the Patient's Own Cornea

The aim of this study is to compare the healing of corneal epithelial defects or ulcers on the corneal graft in comparison with the patient's own cornea after treatment with 100%, undiluted autologous serum eye drops. In a retrospective study over 7 years, we analysed 263 treatments with autologous serum eye drops of persistent corneal epithelial defects (erosions [88%] vs. ulcers [12%]). We compared the epithelial healing tendency of patients with defects on their own cornea (51.9%) vs. patients who had previously undergone penetrating keratoplasty (48.1%). Complete epithelial healing during the 28 days of treatment was considered as therapeutic success. In addition, the recurrence rate of the epithelial defects after finishing the therapy was analysed. 88.2% of the epithelial defects healed during 28 days of therapy. The recurrence rate during follow-up was 5.1%. There was no significant difference with respect to success rate between corneal defects on the patient's own cornea (87.8%) and on the graft (88.6%; p = 0.137). There was a significantly lower success rate for corneal ulcers (74.2%) than for erosions (90.3%; p < 0.001). The recurrence rate of erosions was 4.4%, vs. 4.3% in ulcers during follow-up. The results of our study suggest that autologous serum eye drops are a non-invasive and safe alternative treatment for persistent corneal epithelial defects - with no significant difference in patients with a defect on their own cornea vs. defects on the corneal graft. The success rate, but not the recurrence rate, is significantly worse in ulcers than in erosions.

Comparison between Placement of an Amniotic Membrane Contact Lens and Temporary Amniotic Membrane Transplantation

Purpose: We compared the clinical utilities of an amniotic contact lens and temporary amniotic membrane transplantation in patients with persistent corneal epithelial defects.Methods: Patients diagnosed with persistent corneal epithelial defects from November 2019 to July 2022 were randomly assigned to either lens placement for 2 weeks or temporary transplantation for 1 week, and the outcomes were retrospectively analyzed. The best-corrected visual acuity, corneal sensation, tear film break-up time, and corneal opacity were measured before and after the interventions. The treatment success rates, recurrences, and other complications were analyzed during the follow-up period.Results: We placed lenses in 32 patients (32 eyes) and 20 patients (20 eyes) underwent transplantation. In both groups, significant differences in best-corrected visual acuity, corneal sensation, tear film break-up time, and corneal opacity were apparent after intervention vs. before. None of the parameters showed any significant differences in terms of their rates of change.Conclusions: In patients with persistent corneal epithelial defects, amniotic contact lens placement is an effective outpatient procedure and is not inferior to temporary amniotic membrane transplantation.

The Effect of Amniotic Membrane Extracted Eye Drop on Repairing The Corneal Epithelial in Patients after Trans-Epithelial Photorefractive Keratectomy: An Interventional and Historical Study.

Recent studies imply extensive applications for the human amniotic membrane (hAM) and its extract in medicine and ophthalmology. The content of hAM meets many requirements in eye surgeries, such as refractive surgery as the most important and commonly used method for treating the dramatically increasing refractive errors. However, they are associated with complications such as corneal haziness and corneal ulcer. This study was designed to evaluate the impact of amniotic membrane extracted eye drop (AMEED) on Trans-PRK surgery complications. This randomized controlled trial was performed during two years (July 1, 2019-September 1, 2020). Thirty-two patients (64 eyes), including 17 females and 15 males, aged 20 to 50 years (mean age of 29.59 ± 6.51) with spherical equivalent between -5 to -1.5 underwent Trans Epithelial Photorefractive Keratectomy (Trans-PRK) surgery. One eye was selected per case (case group) and the other eye was considered as control. Randomization was done using the random allocation rule. The case group was treated with AMEED, and the artificial tear drop every 4 hours. The control eyes received artificial tear drops instilled every 4 hours. The evaluation continued for three days after the Trans-PRK surgery. A significant decrease in CED size was found in the AMEED group on the second day after surgery (P=0.046). Also, this group had a substantial reduction in pain, hyperemia, and haziness. This study showed that AMEED drop can increase the healing rate of corneal epithelial lesions after Trans- PRK surgery and reduce the early and late complications of Trans-PRK surgery. Researchers and Ophthalmologists should consider AMEED as a selection in patients with persistent corneal epithelial defects and patients who have difficulty in corneal epithelial healing. We understood AMEED has a different effect on the cornea after surgery; therefore, the researcher must know AMEED's exact ingredients and help expand AMEED uses (registration number: TCTR20230306001).

No Pain, No Gain – Topical Anesthesia-Induced Keratopathy

Topical anesthesia is an indispensable element of modern ophthalmic practice, most valuable during minor procedures and ocular examinations. However, regularly applied and prolonged use of local anesthetics may cause significant ocular damage. The spectrum of adverse effects is heterogeneous, ranging from mild conjunctival injection with superficial punctate keratopathy to persistent corneal epithelial defects, endothelial decompensation, ulcer formation, secondary infectious keratitis, and possible corneal perforation [1], [2]. Hence, timely identification of the underlying cause is essential to initiate targeted therapeutic measures. However, as topical anesthesia-induced keratopathy is a rare entity in Switzerland and its clinical picture may resemble infectious keratitis [3], the ophthalmologistʼs initial diagnosis poses a challenging task. This case report aims to further raise awareness about topical anesthetic abuse keratopathy.

Prolonged Inflammation and Infectious Changes in the Corneal Epithelium Are Associated with Persistent Epithelial Defect (PED).

Purpose: Failure of rapid re-epithelialization within 10-14 days after corneal injury, even with standard supportive treatment, is referred to as persistent corneal epithelial (CE) defect (PED). Though an array of genes regulates reepithelization, their mechanisms are poorly understood. We sought to understand the network of genes driving the re-epithelialization in PED. Method: After obtaining informed consent, patients underwent an ophthalmic examination. Epithelial scrapes and tears samples of six PED patients and six individuals (control) undergoing photorefractive keratectomy (PRK) were collected. RNA isolation and quantification were performed using either the epithelial scrape taken from PED patients or from HCLE cells treated with control tears or tears of PED patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of a few important genes in CE homeostasis, inflammation, and cell-cell communication, viz., Kruppel-like factor 4 (KLF4), GPX4, IL6, TNFα, STING, IL8, desmoglein, and E-cadherin, among others. Their expressions were normalized with their respective housekeeping genes and fold changes were recorded. KLF4 localization and MMPs activity was carried out via immunofluorescence and zymography, respectively. Results: KLF4, a transcription factor important for CE homeostasis, was upregulated in tears-treated HCLE cells and downregulated in PED patients compared to the healthy PRK group. Cell-cell communication genes were also upregulated in tears-treated cells, whereas they were downregulated in the PED tissue group. Genes involved in proinflammation (IL6, 282-fold; TNFα, 43-fold; IL8, 4.2-fold) were highly upregulated in both conditions. MMP9 activity increased upon tears treatment. Conclusions: This study suggests that tears create an acute proinflammatory milieu driving the PED disease pathology, whereas the PED patients scrapes are an indicator of the chronic stage of the disease. Interferons, pro-inflammatory genes, and their pathways are involved in PED, which can be a potential target for inducing epithelialization of the cornea.

Clinical observation of recombinant human nerve growth factor in the treatment of neurotrophic keratitis.

To characterize changes of corneal nerve morphology and tear indices in patients with neurotrophic keratitis (NK) treated with recombinant human nerve growth factor (rhNGF). In a prospective observational study, six patients (nine eyes) were locally treated with rhNGF. Visual acuity, corneal fluorescein staining score, the heights of the tear river, lipid layer thickness (LLT), tear ferning (TF) test, conjunctival impression cytology (CIC) examination, the densities of cornea subbasal nerve fibers were determined before and after treatment. Compared with baseline, there was a significant difference in corneal fluorescence staining scores (P<0.01); all patient corneal epithelial defects recovered completely within 8wk, but there was no significant improvement in the height of the tear river (P=0.202). LLT was significantly increased when compared with baseline (P=0.042); however, the function of conjunctival goblet cells and mucin content did not significantly improve using the TF test and CIC examination (P=0.557, P=0.539). After 8wk of treatment, the average corneal subbasal nerve fiber density increased significantly (P<0.01), as did the number of corneal nerve fiber branches (P=0.001). RhNGF can increase the density of corneal subbasal nerve fibers, promote the healing of persistent corneal epithelial defects and corneal ulcers in patients with NK, also improving tear function partially.

Persistent corneal epithelial defect associated with sleeping position: A case report

Persistent corneal epithelial defect associated with sleeping position: A case report

Healing of Chemical Injury-Related Persistent Corneal Epithelial Defects With Topical Insulin.

The purpose of this study was to evaluate the effectiveness of insulin eye drops for treating refractory persistent epithelial defects (PEDs). A prospective, single-center, case series was performed from March 2020 to September 2021. All patients were prescribed insulin eye drops for refractory PEDs that failed on maximum standard medical treatment (including serum eye drops). The drops were used 4 times/day. Patients were followed up at 2 weekly intervals with full slitlamp examination and serial anterior segment photography. The primary end point was resolution of the epithelial defect. Eleven eyes of 10 patients were treated with insulin eye drops. The mean age of the cohort was 45.4 + 25 years with a mean follow-up of 195.7 + 114.3 days after re-epithelization. The most common causative condition was chemical injury (n = 5, 60%). Mean baseline PED defect was 41.3 + 55.2 mm 2 . Nine of 11 eyes (82%) fully re-epithelized within a mean time of 62.3 + 34.6 days (range 14-112). In 2 patients who did not achieve re-epithelization, one had a reduction in size from 12.25 mm 2 to 4.5 mm 2 and the other had no response. No recurrence in defect was observed in the group that had fully re-epithelized. This study showed that the use of topical insulin eye drops led to a successful resolution of PED in 9 of 11 cases. We demonstrate the use of insulin for closure of PEDs in chemical eye injury. Larger controlled studies are required to further evaluate this novel therapy.

Research progress on the pathogenesis of diabetes-related dry eye

In recent years, with the further understanding of medical circles on diabetic ocular complications, the ocular surface abnormalities of diabetes has drawn increasing concerns. Nearly 50% of diabetic patients suffer from dry eye symptoms. The main manifestations of diabetes related dry eye were abnormal lacrimal secretion, poor lacrimal stability, decreased corneal sensitivity, persistent corneal epithelial defect and even corneal ulcer, which were mainly related to the changes of structure and function of lacrimal gland, the decrease of goblet cells in conjunctiva, the abnormality of meibomian gland function and the degeneration of corneal nerve caused by diabetes. In this paper, we summarized and analyzed the recent research progress on the effect of diabetes on lacrimal film, corneal innervation and lacrimal gland innervation, and the correlation between oxidative stress, advanced glycation end products and diabetes-related dry eye, to explore the pathogenesis of diabetes-related dry eye and to provide reference for clinical diagnosis, treatment and research.

The progress in techniques for culturing human limbal epithelial stem cells.

In vitro culture of human limbal epithelial stem cells (hLESCs) is crucial to cell therapy in the treatment of limbal stem cell deficiency, a potentially vision-threatening disease that is characterized by persistent corneal epithelial defects and corneal epithelium conjunctivalization. Traditionally, hLESCs are cultivated based on either limbal tissue explants or single-cell suspensions in culture media containing xenogenous components, such as fetal bovine serum and murine 3T3 feeder cells. Plastic culture dishes and human amniotic membranes are classical growth substrates used in conventional hLESC culture systems. The past few decades have witnessed considerable progress and innovations in hLESC culture techniques to ensure a higher level of biosafety and lower immunogenicity for further cell treatment, including complete removal of xenogenous components from culture media, the application of human-derived feeder cells, and the development of novel scaffolds. Three-dimensional artificial niches and three-dimensional culture techniques have also been established to simulate the real microenvironment of limbal crypts for better cell outgrowth and proliferation. All these progresses ensure that in vitro cultured hLESCs are more adaptable to translational stem cell therapy for limbal stem cell deficiency.

Efficacy of Autologous Serum Gel in Neurotrophic Persistent Corneal Epithelial Defects Combined with Lagophthalmos.

To investigate the efficacy of autologous serum gel in patients with lagophthalmos combined with neurotrophic persistent corneal epithelial defects (PEDs). This is retrospective, case-series study enrolled 15 patients with lagophthalmos complicated by neurotrophic PEDs refractory to medical treatment including autologous serum eye drops. They were treated with autologous serum gel in conjunction with conservative treatment. The following information was collected from medical records: demographics, underlying diseases, and past ocular history. PEDs healing time was evaluated with visual acuity, visual analog scale (VAS) scores, esthesiometer scores, and the areas of the epithelial defects. Six men and nine women with a mean age of 63.3 ± 9.9years were included. The most common cause of the neurotrophic PEDs and lagophthalmos in this group was postherpetic infection (46.7%) and cerebral hemorrhage (26.7%) each. Two months following treatment with autologous serum gel, there was a reduction in the area of the epithelial defects (from 19.2 ± 9.9 to 0.6 ± 1.5mm2) and a significant improvement in best-corrected visual acuity (BCVA) (from 0.8 ± 0.5 to 0.5 ± 0.4 logMAR) and VAS scores (from 5.1 ± 1.1 to 2.1 ± 0.6) in 13 eyes (87%). Among the 11 completely healed eyes, the mean epithelial healing time was 3.2 ± 1.8weeks. Autologous serum gel reduces symptoms and promotes corneal epithelialization of refractory neurotrophic PEDs in patients with lagophthalmos. Therefore, it may be well tolerated and a beneficial addition in the management of neurotrophic PEDs in patients with lagophthalmos.

Abstract 11 Outcome of Patients Treated with Umbilical Cord Blood and Homologous Serum Eye Drops

IntroductionSeveral authors have demonstrated the safety and efficacy of CBS eye drops in the treatment of severe DE with or without Sjogren’s syndrome (SS-I), ocular graft versus host disease (GVHD), persistent corneal epithelial defects, recurrent corneal erosions, chemical burns, and neurotrophic keratitis.ObjectiveTo compare the efficacy of cord blood serum (CBS) and adult donor peripheral blood serum (PBS) eye drops (prepared, standardized, and controlled in the Emilia Romagna Cord Blood Bank) in the treatment of severe dry eye disease (DED), a multicenter randomized, double masked, crossover clinical trial was designed.MethodsSixty patients diagnosed with severe DED associated with persistent corneal epithelial defects were randomized and equally assigned to group A (treated with CBS) or group B (treated with PBS) , eye drops administered 8 times/day for 1 month. Primary outcome was the pre-treatment and post-treatment change in corneal fluorescein staining. Secondary outcomes included the pretreatment and post-treatment change in ocular surface disease index (OSDI), questionnaire and Visual Analogue Score (VAS) of subjective symptoms, Schirmer I test, tear break-up time, and conjunctival staining. Patients with relapse in signs or symptoms after further 2 months switched to the remaining group for one additional month.ResultsCorneal staining was more significantly reduced after CBS treatment; both VAS and OSDI score reduction was observed in both groups, but group A reported significantly less grittiness and pain. Nineteen patients shifted in the crossover period. The within individual comparison confirmed a better recovery in the CBS treatment period. Epidermal growth factor, transforming growth factor, and platelet-derived growth factor content was associated with reduction of epithelial damage. Levels of interleukins were positively associated with symptoms decrease.DiscussionDED signs improved after both CBS and PBS treatments with potential advantages of CBS for subjective symptoms and corneal damage reduction. In addition to the very important therapeutic value of EDHO products, considering the CB units not suitable for transplantation, we have identified novel non-wasteful clinical applications of those allogeneic biological products, resulting in an increase of ethical motivation of families generously donating CB for public benefit.Figure 1.Slit-lamp photographs with fluorescein staining in patient running both period 1 and period 2 of the study. Before PBS treatment, the corneal epithelium was stained diffusely (top left). One month after treatment, the severity of the damage decreased, especially in the central area (top right). Two months after the end of the treatment, the level of epithelial damage worsened and patient entered period 2 (bottom left). After 1 month of CBS treatment, a diffuse decrease in staining was observed in all areas. In this patient, a better improvement was observed after the CBS treatment compared with the PBS treatment.

In Vivo Evaluation of Validated Targets from High Throughput Screening Models for Sulfur Mustard Ocular Injury

This work was conducted in an effort to develop medical countermeasures to treat exposure to toxicants that can be utilized in a terrorism or warfare scenario. Chemical injuries to the eyes are true ocular emergencies because of their high potential to inflict rapid and enduring tissue damage. The cornea and other ocular surface tissues are particularly susceptible to chemical exposures such as sulfur mustard (SM), and long‐term prognosis can be poor due to progressive corneal pathologies. Chronic and delayed complications include persistent corneal epithelial defects, dry eye, corneal opacification, and corneal neovascularization. Such long‐term complications can lead to permanent discomfort and vision deficits or blindness despite the best current treatment regimens. To identify novel therapeutic targets, we had carried out siRNA‐mediated high throughput screening (HTS) using human corneal epithelial cell models of SM exposure. Over 3000 genes identified as differentially regulated after SM ocular exposure by previous microarray studies were tested for their functions involved in cell viability and IL‐8 production. The current study transitioned eight validated targets from the HTS to a mouse model of SM‐induced ocular injury. Interestingly, four out of the eight targets, PSMA1, PSMA2, PSMD7 and FBXO5, were subunits of proteasomes or E3 ubiquitin ligase complexes. The ubiquitin‐proteasome pathway maintains protein homeostasis and therefore important cellular functions through the degradation of misfolded, redundant, and damaged proteins. Treatment with the proteasome inhibitor bortezomib in the first two weeks after SM ocular exposure greatly promoted the rate and number of corneal neovascularization, which is a key feature of a delayed injury phase. Such outcomes were also observed with treatment with another proteasome inhibitor, carfilzomib. In addition to proteasome subunits, GABRR1 (GABA type A receptor subunit rho‐1) was among the validated targets from the HTS. We learned that muscimol, a GABA type A receptor agonist, significantly decreased corneal neovascularization during 8‐week observation periods. Taken together, these outcomes demonstrated the effectiveness of our systemic approach to identify novel molecular signaling pathways implicated in toxicant‐induced ocular injuries and future studies for potential drugs. For example, our future studies include investigating proteasome‐mediated protein regulation of angiogenic factors in response to SM ocular exposure and testing the therapeutic potential of proteasome agonists. Some small molecule proteasome agonists such as chlorpromazine and imidazoline were identified in recent years and have been studied for their efficacy in treating different diseases such as neurodegeneration, cancer, and autoimmunity.

Persistent Epithelial Defects Caused by Limbal Deficiency for Various Causes

Purpose: We report the process of treating persistent corneal epithelial defects due to limbal deficiency in a patient who underwent surgery for ptosis, recurrent pterygium, and senile cataract for 3 weeks.Case summary: A 65‐year‐old male patient underwent cataract surgery 4 months ago and visited this hospital with persistent inflammation of the left cornea that started 2 months ago. The patient underwent blepharoplasty and pterygium surgery at the same time 3 weeks before cataract surgery. At the first visit, severe conjunctival injection and an oval‐shaped corneal epithelial defect with a size of 3 × 5 mm in the center of the cornea were seen. As the result of the eyelid eversion test, fibrotic scar tissue due to the non‐absorbable suture used during the upper eyelid blepharoplasty was observed and surgically removed. The corneal epithelial defect site became smaller, but the atrophy of the corneal stroma was sustained, and the amniotic membrane was tripled and permanent amniotic membrane transplantation was performed. Corneal epithelial defects have improved with postoperative best‐corrected visual acuity of 0.15.Conclusions: Sufficient recovery period between serial multiple surgeries is required to reduce the occurrence of complications like persistent epithelial defects.