Purpose: To investigate whether treatment with artificial tears inhibits the development of experimental immune-mediated blepharoconjunctivitis (EC).
Methods: Brown Norway rats were immunized with ovalbumin (OVA) or ragweed (RW) emulsified in complete Freund's adjuvant. Fourteen days after immunization, the rats were challenged with the same antigen (Ag) in eye drops. Treated rats were administered artificial tears by eye drops immediately after, 15 min after, or 30 min after the Ag challenge. Treatment doses of 2, 4, or 8 drops per eye were evaluated. Twenty-four hours after the Ag challenge, the rats were killed and their eyes were harvested for histological studies.
Results: Treatment with artificial tears immediately after and 15 min after challenge with partially insoluble RW Ag suppressed infiltration of inflammatory cells into the conjunctiva. Inhibition was not observed at any time following challenge with OVA Ag, which is a soluble protein. The treatment dose of artificial tears administered did not affect the extent of inhibition of EC following challenge with either Ag.
Conclusions: Treatment with artificial tears by eye drops inhibited the development of EC induced by the partially insoluble RW Ag when administered within 15 min of the Ag challenge.