This would be a single-center prospective, open labeled, non-randomized interventional study. This study is an Investigator Initiated Study (IIS). The Ethics Committee of the LV Prasad Eye Institute, Hyderabad, would prospectively approve this study. This study would be conducted in strict adherence to the tenets of the Declaration of Helsinki, ICH GCP E6 (R2), Indian GCP Guidelines and New Drugs and Clinical Trial Rules 2019 and associated amendments and current National Ethical Guidelines for Biomedical and Health Research Involving Human Participants and Current National Stem Cell Research Guidelines and New Drugs and Clinical Trial Rules 2019.
Once the participants are found to be suitable for limbal transplant surgery, the patients will be administered written informed consent and audio /visual consent as per regulations. Detailed ophthalmic examination will be done to ensure that the patient is eligible for the trial.
All the screening procedures will be accomplished within 14± 7days. On Day 0 that is the date of surgery a Unique Participant Identification Number (UPIN) will be assigned to each patient and it would be in addition to hospital medical record number. The surgery will be done under local or general anesthesia (depending on age and patient preference).
In this prospective interventional study patients with unilateral superficial corneal scars will undergo a surgical procedure. Limbal ring from a cadaveric donor tissue, which is therapeutically accepted and serologically tested, is collected. This tissue will then be cultivated in the stem cell biology laboratory using standardized culture technique. Briefly the limbal tissue will be cut up into small pieces and digested overnight using an enzyme (Collagenase L). The cells obtained from the digest will be cultured on a petri-dish using 2% serum and growth factors. The cultured cells will be passaged three times to remove all epithelial cells from the culture.
In the second procedure, the eligible patients will undergo corneal transplant surgery, when the central corneal epithelium will be removed using a surgical sponge. 0.1ml of stromal cells in a concentration of 0.5x106 cells/µl diluted in the thrombin component of fibrin glue (TISEEL, Baxter) will be applied to the debrided corneal stroma. A soft bandage contact lens will be placed over the cornea at the end of the procedure. The patient will receive topical antibiotic and steroid eye drops in the post-operative period. Periodic comprehensive ophthalmic evaluation along with anterior segment optical coherence tomography (ASOCT) scanning and slit-lamp photography will be done at Day 1, Day 7, Day 30, Day 90, Day 180 and Day 360 and 720 Days post-surgery. The primary outcome measure of this study is to note any ocular or systemic adverse effects of this intervention at the various post-operative time points. The secondary outcome measures are visual improvement and change in the density and appearance of the corneal scarring and other pathologies after treatment.
