Despite exposure to unwashed fingertips and contact lenses the eye rarely succumbs to infection. This is in large part attributable to a very robust innate immune system that comprises both physical and chemical defences. Antimicrobial peptides such as defensins and cathelicidins are an important component of the latter. Studies have shown that the cells of the ocular surface are important sources of antimicrobial peptides and that loss of the peptides significantly reduces defence against both bacterial and fungal pathogens. In addition to providing endogenous innate immune protection antimicrobial peptides have significant therapeutic potential as topical drop formulations for the treatment of eye infection and as prophylaxis in the form of antimicrobial contact lenses. Here the current knowledge on the expression and role of antimicrobial peptides endogenously expressed at the ocular surface (cornea and conjunctiva) will be addressed. Also antimicrobial contact lenses and the potential use of a peptide derived from the amphibian antimicrobial peptide Esculentin for the treatment of bacterial keratitis, a potentially vision threatening corneal infection most commonly associated with contact lens wear, will be discussed.
Dr. Alison McDermott is a Professor of Optometry and Vision Sciences and the Scientific Director of The Ocular Surface Institute at The University of Houston College of Optometry. Dr. McDermott received her BSc. and PhD in biochemistry from the University of Surrey, and Imperial College, UK, respectively. After post-doctoral positions at Cornell University and McMaster University in Canada she joined the lab of veterinary ophthalmologist Dr. Christopher Murphy at the University of Wisconsin Madison and so began her career in eye research. She joined the University of Houston College of Optometry in 1998 where she has an active federally funded research lab and teaches professional students of optometry and graduate students. The primary goal of her research program is to gain a better understanding of the ocular surface epithelia at the cellular and molecular level which will lead to treatment strategies for ocular surface inflammatory and infectious disease and wound healing following injury and refractive surgery. The major focus of her research is to investigate the direct antimicrobial and immunomodulatory properties of antimicrobial peptides such as defensins and cathelicidin at the ocular surface. She is also involved in collaborative projects to develop antimicrobial surfaces, including contact lenses.