The Effect of Staphylococcus aureus Phage Lysate Vaccine on a Rabbit Model of Staphylococcal Blepharitis, Phlyctenulosis, and Catarrhal Infiltrates

Abstract

To evaluate the effect of Staphylococcus aureus phage lysate (SPL) vaccination on the development of blepharitis, corneal phlyctenules, and catarrhal infiltrates and on the development of antibodies and the delayed-type hypersensitivity response to S. aureus. Eighty rabbits received an intradermal immunization of cell wall-complete Freund's adjuvant followed by a booster immunization. Rabbits were given topical applications of viable S. aureus in both eyes and 40 rabbits received subcutaneous SPL vaccinations. Clinical observations were made weekly. An enzyme-linked immunosorbent assay was used to measure IgG, IgA, and IgM antibody levels to ribitol teichoic acid in sera, corneas, and tears. The delayed-type hypersensitivity response was evaluated by skin testing after subcutaneous injection of staphylococcal antigens. In the SPL-vaccinated group, phlyctenules developed in eight of 40 rabbits while blepharitis developed in 13 of 40. In the nonvaccinated group, phlyctenules developed in three of 40 rabbits and blepharitis developed in five of 40. The number of rabbits with blepharitis was significantly higher in the SPL-vaccinated group than in the nonvaccinated group. In general, the antibody response to ribitol teichoic acid was enhanced, while the delayed-type hypersensitivity response to S. aureus was depressed. Vaccination with SPL was not found to have a beneficial effect on the development of blepharitis, phlyctenules, and catarrhal infiltrates in our rabbit model.