EuCornea medal lecture highlights potential of cultivated stem cells for ocular surface disease reconstruction
Autologous cultivated limbal stem cell grafts give good and stable long-term clinical results and have several advantages in the reconstruction of compromised ocular surface due to disease or severe trauma, said Prof Paolo Rama in his EuCornea Medal Lecture at the Opening Ceremony of the 7th EuCornea Congress.
“Stem cells can be cultured under appropriate culture conditions and can be implanted and remain viable and functional in the long-term. Furthermore, the surgical procedure is simple and reproducible, and cells on fibrin can easily be handled and transported,” he said.
Prof Rama noted that research on corneal stem cells dates back almost 25 years with ground-breaking work by his Italian colleagues Graziella Pellegrini PhD and Michele De Luca MD, initially showing that cultured limbal stem cells could be used therapeutically for the regeneration of corneal epithelium.
In a wide-ranging lecture, Prof Rama explained that ocular surface diseases are challenging and complex and that corneal transparency is the final goal of treatment.
“The ocular surface needs to be considered as a functional unit, with a wide approach, precise diagnosis and staging, step-by-step treatment and reconstruction. The recipient micro-environment is crucial for the stem cells engraftment and long-term survival,” he said.
Prof Rama said that recent months have seen a major breakthrough for regenerative medicine with European Commission approval for Holoclar™ as a commercially available stem-cell therapy for use in cases of blindness caused by burning.
This approval follows on from the work of Prof Rama and colleagues, who used autologous limbal stem cells cultivated on fibrin to treat 112 patients with corneal damage, most of whom had burn-dependent limbal stem-cell deficiency.
In that study, permanent restoration of a transparent, renewing corneal epithelium was attained in 76.6% of eyes. The failures occurred within the first year and restored eyes remained stable over time, with up to 10 years of follow-up, he said.
While autologous cultivated limbal stem cell grafts offer clear advantages over many current methods of ocular surface reconstruction, the complexity and costs of the procedure may inhibit its initial uptake, said Prof Rama.
Nevertheless, he was convinced that cultivated stem cells offered too many advantages to not gain more widespread use in clinical practice.
He compared the situation to that which existed in cataract surgery over 20 years ago before the advent of phacoemulsification.
“Phacoemulsification took more than 20 years of research and development to become a routine and safe procedure for cataract surgery. So you should ask your colleagues in cataract if they consider as misguided the early efforts and investment and initial high costs of the phacoemulsification procedure. The reality is that innovative procedures are often not convincing and convenient in the beginning, but later may show clear advantages and become routine,” he said.