New corneal therapies: From Bench to Bedside
Professor Keith Meek
Professor and Chair of Structural Biophysics Research Group
College of Biomedical and Life Sciences School of Optometry and Vision Sciences
All clinical treatments are underpinned by basic scientific research, sometimes retrospectively, but mostly by forward planning and development, and the UK has historically been at the forefront of such efforts.
Indeed, the Structural Biophysics Group at Cardiff University led by Professor Keith Meek highlights the benefits of high levels of specialisation and multi-disciplinary working in determining positive clinical outcomes for patients.
Patients at high risk of corneal blindness face the twin challenges of possible corneal rejection following a corneal transplant and the worldwide shortage of donated corneas. So, notwithstanding the ongoing stem cell research which is providing some hope (although only really viable in developed nations as cell expansion costs that meet regulatory requirements are too high), it is important to drive towards the removal of the reliance on donor corneal transplantation.
So, specific research initiatives are focusing on developing and successfully testing cell- free, pro-regeneration implants comprising genetically produced human collagen (Collagen is a hard, insoluble and fibrous protein that makes up one-third of the protein in the human body) as safe, reliable alternatives to human donor transplants in a range of high-risk corneal transplantation patients. a completely synthetic collagen mimetic (a material imitating collagen) has been developed to treat corneal diseases. Successful testing in a simple organ system like the cornea will in future allow for the extension to more complex applications such as skin and cardiac regeneration.
This method may also be applied eventually to “Corneal crosslinking”, which is now widely used to treat progressive keratoconus and other conditions. However, the conventional treatment is uncomfortable, and takes over 30 minutes, leaving patients vulnerable to infection. Quicker, pain-free methods are being developed in the Cardiff laboratory (including the St Thomas’/Cardiff iontophoresis protocol) that could translate into clinical practice within a few years.
Also, the biophysical and biomechanical methods that Professor Keith Meek and his team have developed to study the cornea have applications elsewhere in the eye. For example, plaque brachytherapy is used to treat ocular cancers within the eyeball. A radioactive plaque is placed externally on the white sclera and radiation passes through the eyeball into the eye to kill the cancer cells. However, the extent to which the radiation destroys the scleral tissue is unknown, so removal of the eye is the usual option if the initial therapy fails. Basic studies are being carried out to measure the changes in the irradiated sclera with the longer term aim of strengthening the sclera to make it more resistant to radiation damage and thus permit secondary irradiation if necessary, rather than removal of the eye.