About KLAL-Pro
KLAL-Pro is an eye bank prepared, partial thickness, limbal epithelial stem cells (LESCs)-enriched keratolimbal allograft tissue. It can be transplanted to the ocular surface to serve as a treatment for unilateral or bilateral limbal stem cell deficiency (LSCD).
The Eversight Research & Development team—under the leadership of Onkar B. Sawant, PhD—and ocular surface stem cell transplant surgeon Nambi Nallasamy, MD, of University of Michigan’s Kellogg Eye Center, pioneered the development of KLAL-Pro.
It offers several advantages over surgeon preparation of KLA tissue as it is ready-to-use, and both dissection depth and allograft thickness are confirmed by OCT.
Eye bank innovation
As of April 2025, Eversight is the only eye bank preparing KLAL-Pro.
KLAL-Pro is skillfully dissected by an eye bank technician to selectively remove excess posterior stroma that is present underneath the Palisades of Vogt (PoV), and to remove excess scleral tissue. Confirmation of the desired depth of dissection is performed with optical coherence tomography (OCT).
The KLAL-Pro tissue preparation protocol was designed with ocular surface stem cell transplant surgeons to ensure optimal, replicable results. This reduces transplantation of excess donor tissue that does not contain LESCs.
Transplantation
The KLAL-Pro transplantation process begins with the removal of the fibrovascular pannus from the patient eye. Two or three KLAL-Pro segments collected from one or two donor eyes can be used for a treatment of unilateral or bilateral LSCD.
KLAL-Pro tissues are partial thickness, preprocessed lenticules that are meticulously prepared to ensure optimal stem cell viability. To ensure correct orientation, a dot is placed on the anterior surface. The KLAL-Pro tissue is securely affixed onto the patient eye, providing a stable foundation for ocular surface restoration.
KLAL-Pro segments can be ordered here. Prepared to order, KLAL-Pro is available in these dimensions: 3-4mm anteroposteriorly, up to 180 degrees of donor limbus per segment, and approximately 200-300µm thick. KLAL-Pro is stored and delivered in hypothermic corneal storage solution.
According to recently published literature, limbal stem cells from cadaveric donors are viable up to 7-9 days and results in successful surgical outcomes.1,2
Patient impact
KLAL-Pro offers hope as a durable solution for patients with bilateral LSCD through its regenerative properties.
In early clinical use, KLAL-Pro has been shown to support limbal stem cell expansion and substantial improvements in vision through both KLA and modified Cincinnati procedures.
Building on this success, efforts are now focused on expanding patient data, increasing global accessibility and enhancing stem cell longevity to accelerate visual rehabilitation.
Nambi Nallasamy, MD
“KLAL-Pro grafts minimize excess stromal tissue and streamline the process of ocular surface stem cell transplantation. With appropriate immunosuppression regimens, my patients have had excellent outcomes with KLAL-Pro tissue. KLAL-Pro has already become a key part of my approach to treating limbal stem cell deficiency.”
