New approaches to corneal and ocular surface diseases

RESEARCH into the molecular and cellular regulation of corneal and ocular surface immunity is helping to shed light on the role of inflammation in corneal and ocular surface diseases such as angiogenesis, dry eye disease and transplant rejection, as well as opening up potentially exciting new treatment modalities for such conditions, according to Reza Dana MD, MSc, MPH, who delivered his keynote lecture at the 2013 SOE Congress in Copenhagen, Denmark. 'The stakes are high because after cataract, corneal disease remains the leading cause of non-refractive blindness worldwide,' Dr Dana reminded delegates attending his talk on translational discoveries in cornea and ocular surface diseases. Dr Dana, Claes Dohlman chair in ophthalmology at Harvard Medical School, director of the Cornea Service at Massachusetts Eye and Ear Infirmary and the Harvard Cornea Center of Excellence, and senior scientist at the Schepens Eye Research Institute, gave delegates a broad overview of his research into corneal and ocular surface disease over the past two decades. Dr Dana's work has led to many important novel and unexpected discoveries. His laboratory was the first to discover several distinct populations of highly immature antigen-presenting cells (APCs) – including epithelial Langerhans cells and stromal myeloid dendritic cells – in the cornea, breaking a longstanding dogma that the cornea was devoid of any antigen-presenting cell population. His group was also the first to demonstrate functional lymphatic flow from the cornea to the lymphoid tissues, demonstrating the key role played by these lymphatics in induction of immunity to corneal antigens. 'The concept of antigen sequestration was one of the dogmas of ocular immunology until 10 years ago because it was thought that the main reason we don't see any obvious inflammation in the lens or the cornea is that antigens were just kept in the eye, and the immune system was blind to what was going on in the eye. But we now know that this is not actually true,' he said. Indeed, his group has shown that there is ample trafficking of antigens to the lymphoid tissues, but that immune tolerance keeps the response to these antigens in check.