Abstract
Purpose :
Dry eye disease (DED) and more generally, ocular surface disease, can cause visual dysfunction and be debilitating in severe cases. Topical anti-inflammatory agents are currently used for symptomatic relief; however, a great need exists for more definitive treatment. Benzalkonium chloride (BAK) exposure has been used as a model for ocular surface inflammation that has parallels to DED. Histatins—anti-microbial, histidine-rich peptides in saliva—are known for enhancing oral wound healing. Our lab’s previous research has shown the presence of histatins in lacrimal epithelium, decreased histatin expression in lacrimal glands of patients with DED and improved wound healing when applied in vitro. The purpose of this experiment was to study the effects of histatin-5 treatment on the corneal healing process in vivo, using a murine model of chemically-induced toxic epitheliopathy to simulate dry eye.
Methods :
C57/Bl6 mice (Jackson Laboratories, Bar Harbor, ME) were kept in standard environmental conditions and imaged over the course of the experiment using slit-lamp microscopy and vital dye staining. Ocular surface inflammation was induced by applying BAK dissolved in balanced saline solution (BSS), BID. After induction, mice were sorted into two severity-matched groups and eye drops of either histatin-5 dissolved in BSS or BSS alone were given three times per day. Ocular surface parameters were measured over the course of the experiment comparing topical histatin-5 and BSS control-treated groups. Images were scored by masked observers trained in applying the NEI scoring system outlined.
Results :
We found that topical histatin-5 peptide application improved clinically relevant parameters of ocular surface inflammation and dryness, including the CFS-NEI scoring scale. This suggests utility of histatin-5 in treating toxic epitheliopathy induced by BAK.
Conclusions :
Dry eye disease represents a common clinical finding and patients would benefit greatly from improved treatment options. In the present study, ocular surface inflammation induced by BAK was improved by topical histatin-5 peptide application as compared with control BSS. Future studies with larger sample sizes, other animal models of ocular surface diseases and detailed histologic analysis will be needed.
This is a 2020 ARVO Annual Meeting abstract.