Autologous Corneal Stem Cell Transplant Shows High Success in Repairing Corneal Injuries, Finds Study

"transplanted epithelial stem cells from a healthy eye successfully repaired irreversible corneal injury, restoring at least partial vision in over 90% of patients. Within three months, seven out of 14 patients had fully restored corneas, which increased to 11 by the 12-month mark," the researchers reported in Nature Communications. "By 12 and 18 months, more than 90% of the patients showed successful outcomes, including complete and partial improvements, demonstrating the potential of this approach in treating corneal damage."

The researchers note that limbal stem cell deficiency (LSCD) is a serious ocular condition caused by damage or loss of limbal stem cells, leading to vision impairment, chronic pain, and corneal scarring. Current treatment options are limited, and many involve donor tissues that carry the risk of immune rejection.

Against the above background, Ula V. Jurkunas, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA, and colleagues developed a two-stage manufacturing process using cultivated autologous limbal epithelial cells (CALEC), introducing the first xenobiotic-free, serum-free, and antibiotic-free protocol in the United States to treat blindness caused by unilateral limbal stem cell deficiency. They conducted a single-center, single-arm Phase I/II clinical trial to evaluate its safety and feasibility.

The primary outcomes assessed were feasibility, determined by meeting release criteria, and safety, evaluated based on ocular infection, corneal perforation, or graft detachment. Eligible participants included males and females aged 18 to under 90 years with LSCD who could provide written informed consent. National Eye Institute of the National Institutes of Health funded the study.

Key Findings:

• CALEC grafts met release criteria in 14 out of 15 participants (93%) by the trial's end.
• Intracellular adenosine triphosphate levels after the first stage of manufacturing correlated with colony-forming efficiency (r = 0.65).
• One bacterial infection occurred, but it was unrelated to the treatment, and no other primary safety events were reported.
• Efficacy was assessed based on corneal epithelial surface integrity (complete success) or improving corneal vascularization and/or participant symptoms measured by OSDI and SANDI (partial success).
• Success rates (complete or partial) were 86% at 3 months, 93% at 12 months, and 92% at 18 months.

"The findings strongly support the safety and feasibility of CALEC transplantation, highlighting the need for further studies to assess its therapeutic effectiveness," the researchers concluded.

Reference:

Jurkunas, U. V., Kaufman, A. R., Yin, J., Ayala, A., Maguire, M., Samarakoon, L., Johns, L. K., Parekh, M., Li, S., Gauthier, A., Negre, H., Shaw, K. L., Hernandez Rodriguez, D. E., Daley, H., Dana, R., Armant, M., & Ritz, J. (2025). Cultivated autologous limbal epithelial cell (CALEC) transplantation for limbal tem cell deficiency: A phase I/II clinical trial of the first xenobiotic-free, serum-free, antibiotic-free manufacturing protocol developed in the US. Nature Communications, 16(1), 1-12. https://doi.org/10.1038/s41467-025-56461-1