Effect of tear-specific immunoglobulin A on the adhesion of Pseudomonas aeruginosa I to contact lenses

Purpose: The aims of the study were (i) to determine the immunodominant antigens of Pseudomonas aeruginosa (PaerI) to tear secretory immunoglobulin A (sIgA); (ii) to study the role of sIgA in inhibiting bacterial adhesion to contact lenses. Methods: SDS-PAGE and Western blotting were used to study the interaction of tear sIgA with PaerI;an adhesion assay was used to study the effect of sIgA on the adhesion of PaerI to the contact lenses. Results: The results of our study showed that the immunodominant molecules of PaerI which reacted with tear sIgA were of molecular masses of 105, 50, 45 kDa; the binding of sIgA to PaerI resulted in a reduction of the adhesion of PaerI to worn Etafilcon A contact lenses. Conclusions: In conclusion, PaerI-specific sIgA are present in tears; the immunodominant molecules of PaerI may be adhesins and tear-specific sIgA might play an important role in protecting the eye from contact-lens-induced corneal infection by preventing bacterial attachment to contact lenses and the ocular surface.