Human corneal epithelial extracellular matrix perlecan serves as a site for Pseudomonas aeruginosa binding

Purpose. Previous data has shown that basement membrane associated perlecan serves as a binding site for Pseudomonas aeruginosa in the wounded mouse c ornea. The current study determined whether it also provides a binding site for Pseudomonas aeruginosa in transformed human corneal epithelium. Methods. Bacterial adherence to transformed human corneal epithelial cells grown in normal or in media containing various inhibitors of glycosaminogly can synthesis was tested. Bacterial binding was similarly tested in wild-ty pe and in mutant Chinese hamster ovary cell lines naturally deficient in gl ycosaminoglycan synthesis. Transformed human corneal epithelial extracellul ar matrix also was tested before and after treatment with anti-proteoglycan monoclonal antibodies or heparinase III before bacterial inoculation. Scan ning electron microscopy was used to quantitate adherent bacteria. Intact t ransformed human corneal epithelial cells or extracellular matrix, the latt er either treated or not treated with heparinase III or chondroitin ABC lya se were stained to localize perlecan. Results. Examination of the binding of bacteria to transformed human cornea l epithelial cells (normal media vs with inhibitors) and Chinese hamster ov ary cell lines suggested that bacterial binding was not associated with the surface of either cell type. In contrast, anti-perlecan antibody, as well as heparinase III decreased the binding of bacteria to corneal extracellula r matrix. Fluorescence staining localized perlecan to the extracellular mat rix beneath the corneal epithelial cells. Conclusions. Perlecan localized to the extracellular matrix but not the api cal surface of transformed human corneal epithelial cells, provides a bindi ng site for Pseudomonas aeruginosa.