Presenter: Best limbal stem cell deficiency treatment is with patient’s own cells

SEATTLE – A number of sources – including the fellow eye, the oral mucosa, a family member and cadaver – are available for harvesting the cells necessary to treat limbal stem cell deficiency, according to a presenter here at the American Academy of Optometry plenary session.

Victor L. Perez, MD, told attendees that it must first be determined if the patient has unilateral or bilateral disease.

Victor L. Perez

“You can use keratolimbal autograft if the other eye is normal,” he said. “If it’s bilateral, see how much deficiency there is. If it’s less than 50%, you can get stem cells from a living family member or cadaver. If there’s complete deficiency, you need a lot of cells and would need a limbal allograft from a donor that has passed away.”

Perez said challenges exist with keratolimbal allografts and cadaver donors.

“Patients need to be in suppression after keratolimbal allograft for a while,” he said. “Unfortunately, we don’t have a protocol to determine how long.”

He also noted a poor survival rate in donor cells from cadavers.

“The autograft is the way to do it,” he said; “it comes from the patient themselves.”

Perez explained that a piece of conjunctival flap is dissected to the limbus and placed on the site with fibrin glue, securing the limbal stem cells to the sclera.

“We need to explore that more,” he said. “There are limitations. You cannot take much tissue from the other limbus. And this won’t work for patients with bilateral disease.”

The cultivated limbal epithelial transplant has not been used in the U.S., Perez said. It is a difficult procedure because special facilities are needed to grow these cells.

“We need other sources of stem cells,” he said. “The other eye might not be good. We still don’t know if you can use stem cells from a donor and be immunogenic. We are blessed that we have access to the front part of the eye.”

One possibility is to perform ex vivo cell expansion with the other eye. Another is to take cells from the oral mucosa.

“Harvest mucosal cells from the lip and put it in an empty graft with the same media,” Perez said. “There are many similarities in the environment of the mouth and the eye.

“We can also use the posterior segment of the eye,” he continued. “The retinal pigment epithelium has a lot of plasticity.”

Perez said limbal stem cell deficiency can be caused by chemical and thermal burns, multiple surgeries (especially glaucoma), contact lenses, antimetabolites, infections, neoplasia, radiation, Stevens Johnson syndrome, ocular cicatrizing pemphigoid, chronic limbitis and keratopathy. It can be seen with optical coherence tomography or confocal microscopy.

He noted that the ocular surface must be in good shape before starting any limbal cell therapy.

“Make sure there is no aqueous deficiency and it is well lubricated, be sure any type of anatomical problem is properly treated, and there should be no form of exposure keratopathy or immunosuppression,” he added.

The plenary session was partially sponsored by Primary Care Optometry News.