The ocular surface comprises the conjunctiva, the thin membrane that covers the white sclera of the eye, and the clear cornea which provides a window for the passage of light in to the eye. The overall goal of my research program is to gain a better understanding of the ocular surface at the cellular and molecular level so that we will better equipped to treat ocular surface disease (such as infection and dry eye), improve the wound healing response following refractive surgeries (such as LASIK) and develop artificial corneas that closely mimic the normal tissue and can be used for corneal transplantation.

Currently the major focus of my research is to investigate the functions of defensins and cathelicidin at the ocular surface. Whilst these antimicrobial peptides undoubtedly have a role to play in protecting the ocular surface from microorganisms, evidence from other tissues suggests that they may also act as growth factors, chemotactic factors and regulate cytokine production and immune responses. In the lab we are using a variety of techniques including proliferation and chemotaxis assays, RT-PCR, western blots, immunostaining and enzyme immunoassay to study the non-microbicidal functions of defensins and cathelicidin in the cornea. We are also studying changes in the susceptibility to ocular infection in knockout animals missing defensin or cathelicidin genes to determine which of the several antimicrobial peptides expressed by the ocular surface epithelia are particularly important in defence against infection.

Other ongoing projects include investigating the anti-cancer activity of antimicrobial peptides, the role of inflammation and toll-like receptors in the pathogenesis of the common ocular condition dry eye and studying characteristics of corneal keratocytes and their repair phenotypes. We also have an ongoing collaboration with Dr. Chengzhi Cai of the UH Department of Chemistry to develop surfaces (e.g. contact lenses) with antimicrobial coatings.