Clinical Studies of COMET for Total LSCD: a Review of the Methods and Molecular Markers for Follow-Up Characterizations

Purpose of Review This review outlines the main features of the clinical trials where cultivated oral mucosa epithelial cell transplantation (COMET) was performed, aiming to underscore a link between the clinical outcome and the expression of specific markers during the follow-up of patients, characteristic for a defined epithelium (cornea, oral mucosa, or conjunctiva) or related to vascularization. Recent Findings Currently, little is known about the reasons underlying the success or failure of COMET. To address this issue, we focused on tissue characterization at the molecular level, highlighting the findings concerning angiogenesis. Summary There are several discrepancies in the outcomes of COMET clinical trials. While some corneal/conjunctival markers can be considered reliable for understanding the biological mechanisms that drive corneal repair after transplants, a unique marker specifically expressed in the oral mucosa and an accurate study of the vascularization processes are currently missing. Together, these insights will help forecast successes and failures of these technologies.