Using stem cell therapy

New approaches show exciting potential for stromal regeneration as a treatment of keratoconous

Dermot McGrath

Posted: Saturday, September 1, 2018

Jorge L. Alió

Corneal stromal enhancement based on stem cell therapy seems to be safe and effective and may prove to be a potentially exciting new therapy for the treatment of keratoconus and other corneal dystrophies, according to Jorge L. Alió MD, PhD, speaking at a special session on corneal disease at the World Ophthalmology Congress in Barcelona.

“Based on our results, we believe that adipose‐derived adult stem cells (ADASC) can be a cell source for stromal regeneration and repopulation in diseased corneas. This is a new type of corneal surgery, the beginning of a new approach for the treatment of corneal stromal diseases such as keratoconus,” said Dr Alió.

The ADASC technique consists of implantation of autologous adipose tissue-derived stem cells into corneal stroma. “Adipose stem cells are ideal for this task as they are easily obtained and highly efficient. They allow for keratocyte differentiation in vitro and in vivo and possible autologous use,” said Dr Alió.

The first stage of the research saw Dr Alió and his team develop an experimental animal model using autologous stem cells to produce corneal collagen “in situ”, identify the best carrier for the cells and accomplish experimental corneal stromal enhancement using cells and the selected carrier.
Once this was successfully achieved, the next step was to confirm the experience in human patients affected by corneal stromal disease such as advanced keratoconus.

The pilot clinical study for cell therapy of keratoconus included three groups of five patients each: group 1 with intrastromal injection of autologous ADASC; group 2 with intrastromal implantation of decellularised human corneal stroma; and group 3 with intrastromal implantation of recellularised human corneal stroma with autologous ADASC.

Stem cells were obtained from the adipose tissue of each patient via liposuction. For groups 2 and 3, once the cultured cells were prepared a 9.5-mm diameter intrastromal pocket was created using a femtosecond laser. In group 3, the surgeons used a cannula to transfer more than 1 million cells through the pocket into the stroma.

Groups 2 and 3 showed similar results in terms of visual acuity outcomes and keratometry six months post- surgery.

“When we reviewed these patients at the one-year mark the corneal transparency was very good. The visual condition also improved in most cases, with stable keratometry and corneal thickness. Confocal microscopy showed a significant increase in cells and no complications were reported,” said Dr Alió.

To confirm these results, a multi-centre clinical trial sponsored by the Spanish Ministry of Health is currently being conducted.

Jorge L. Alió: