This study is a longitudinal assessment using a classic dose-escalation study design to assess the safety and maximal tolerated dose (MTD) of locally delivered allogeneic mesenchymal stromal cells (MSC) for promoting corneal repair. The study will be conducted at Illinois Eye and Ear Infirmary located at University of Illinois at Chicago. The study will use digital conjunctival and corneal photography and corneal Scheimpflug Imaging, densitometry, and pachymetry for assessment of safety and corneal wound healing.

The "Safety of Locally Delivered Allogeneic Mesenchymal Stem Cells for Promoting Corneal Repair Study" otherwise known as the "MSC Study," is designed to assess the safety of allogeneic bone marrow-derived MSC secreted factor on the ocular surface via subconjunctival injection of MSC, and also obtain a preliminary observation on the following:

1. Epithelial barrier integrity and/or wound closure.
2. Development of Scarring.
3. Final Visual Acuity.

The objective is to improve clinical outcomes in significant non-healing corneal wounds. To achieve these goals, the MSC Study will include a Phase I dose-escalation safety study.

Inclusion Criteria:

Age:

• Patients 18 years of age or older

Visual Acuity:

• Best corrected distance visual acuity (BCDVA) score ≤ 75 ETDRS letters, (≥ 0.2 LogMAR, ≤ 20/32 Snellen or ≤ 0.625 decimal fraction) in the affected eye.

Ocular Health:

• Patients with moderate to severe chronic corneal epithelial disease in the setting of neurotrophic keratitis, limbal stem cell deficiency, or inflammatory dry eye disease.
• Epithelial disease refractory to all applicable standard / FDA approved non-surgical treatments (e.g., preservative-free artificial tears, gels or ointments; discontinuation of preserved topical drops; anti-inflammatory therapy, and soft bandage contact lens).
• Evidence of impaired epithelial barrier manifested by fluorescein staining of the epithelium with a score 6 or higher by National Eye Institute grading.
• No objective clinical evidence of improvement since the last visit (≤50% reduction in fluorescein staining or ≤50% reduction in longest diameter of the epithelial defect).
• Patients with stage 1 (no epithelial defect) stage 2 (persistent epithelial defect, PED; without stromal loss) or stage 3 (corneal ulcer; with stromal loss) neurotrophic keratopathy 28-30 limited to ≤80% corneal diameter. Stromal loss in corneal ulcers cannot exceed 50%.
• Etiology of all persistent epithelial defects and corneal ulcers will be neurotrophic in nature. Neurotrophic keratopathy may be due to previous trauma such as chemical and thermal burns, systemic diseases like diabetes, post-infectious keratitis such as herpetic disease, or cranial nerve V palsies such as surgery for trigeminal neuralgia.
• PED or corneal ulceration refractory to one or more conventional non-surgical treatments (e.g., preservative-free artificial tears, gels or ointments; discontinuation of preserved topical drops and medications that can decrease corneal sensitivity; therapeutic contact lenses).
• No objective clinical evidence of improvement in the PED or corneal ulceration within the week prior to study enrollment (e.g., ≤50% reduction in longest diameter in 1 week).
• Evidence of decreased corneal sensitivity (≤ 4 cm using the Cochet-Bonnet aesthesiometer) within the area of the PED or corneal ulcer and outside of the area of the defect in at least one corneal quadrant.

Exclusion Criteria:

Visual Acuity:

• Patients with severe vision loss in the affected eye with no potential for visual improvement in the opinion of the investigator as a result of the study treatment.

Ocular Health:

• Any active ocular infection (bacterial, viral, fungal or protozoal) or active ocular inflammation not related to PED in the affected eye.
• History of any ocular surgery (including laser or refractive surgical procedures) in the affected eye within the three months before study enrollment. An exception to the preceding statement will be allowed if the ocular surgery is considered to be the cause of the PED. Ocular surgery in the affected eye will not be allowed during the study treatment period and elective ocular surgery procedures should not be planned during the duration of the follow-up period.
• Prior surgical procedure(s) for the treatment of a PED (e.g., complete tarsorrhaphy, conjunctival flap, etc.) in the affected eye with the exception of amniotic membrane transplantation. Patients previously treated with amniotic membrane transplantation may only be enrolled two weeks after the membrane has disappeared within the area of the PED or corneal ulcer or at least six weeks after the date of the amniotic membrane transplantation procedure. Patients previously treated with Botox (botulinum toxin) injections used to induce pharmacologic blepharoptosis are eligible for enrollment only if the last injection was given at least 90 days prior to enrollment in the study.
• Anticipated need for punctual occlusion during the study treatment period. Patients with punctual occlusion or punctual plugs inserted prior to the study are eligible for enrollment provided that the punctual occlusion is maintained during the study.
• Evidence of corneal ulceration involving the posterior third of the corneal stroma, corneal melting or perforation in the affected eye.
• Presence or history of any ocular or systemic disorder or condition that might hinder the efficacy of the study treatment or its evaluation, could possibly interfere with the interpretation of study results, or could be judged by the investigator to be incompatible with the study visit schedule or conduct (e.g., progressive or degenerative corneal or retinal conditions, uveitis, optic neuritis, poorly controlled diabetes, autoimmune disease, systemic infection, neoplastic diseases).
• Any need for or anticipated change in the dose of systemic medications known to impair the function of the trigeminal nerve (e.g., neuroleptics, antipsychotic and antihistamine drugs). These treatments are allowed during the study if initiated prior to 30 days before study enrollment provided they remain stable throughout the course of the study treatment periods.

Study Procedures:

• Known hypersensitivity to one of the components of the study or procedural medications (e.g., fluorescein).
• History of drug, medication or alcohol abuse or addiction.
• Use of any investigational agent within 4 weeks of screening visit.
• Participation in another clinical study at the same time as the present study.
• Participants who are pregnant at the time of study enrollment.