Photochemotherapeutic strategies against Acanthamoeba keratitis.

Here, we determined the potential of photochemotherapy, namely the application of photodynamic compounds followed by exposure to a suitable source of UV-visible radiation against corneal pathogen, Acanthamoeba. Organometallic macromolecule, tin porphyrin [Sn(IV)porphyrin] was synthesized and purity confirmed using nuclear magnetic resonance spectroscopy. The Sn(IV)porphyrin was tested against a keratitis isolate of Acanthamoeba castellanii belonging to the T4 genotype using growth and viability assays. The effects of Sn(IV)porphyrin on A. castellanii binding to and cytopathogenicity of human corneal epithelial cells in vitro were tested. The metalloporphyrin showed potent amoebistatic effects. The tin porphyrin inhibited amoebae binding to and cytopathogenicity of corneal epithelial cells. By using derivatives of photodynamic compounds [Sn(IV)porphyrin-antibody conjugates] for selective targeting of the parasite together with appropriate selection of light source will determine the potential of photochemotherapy against Acanthamoeba keratitis.