title: Chlorin e6 mediated photodynamic inactivation for multidrug resistant Pseudomonas aeruginosa keratitis in mice in vivo.
abstract: Following corneal epithelium scratches, mouse corneas were infected with the multidrug resistant (MDR) P. aeruginosa strain PA54. 24 hours later, 0% (for control group), 0.01%, 0.05% or 0.1% Chlorin e6 (Ce6), a second generation photosensitizer derived from chlorophyll, was combined with red light, for photodynamic inactivation (PDI). 1 hour or 2 days later, entire mouse eyes were enucleated and homogenized for counting colony forming units (CFU) of P. aeruginosa. For comparison, 0.1% Ce6 mediated PDI was started at 12 hours post infection, and 0.005% methylene blue mediated PDI 24 hours post infection. Clinical scores of corneal manifestation were recorded daily. Compared to the control, CFU 1 hour after PDI started 24 hours post infection in the 0.01% Ce6 and 0.05% Ce6 groups were significantly lower (more than one log10reduction), the CFU 2 days post PDI higher in the 0.1% Ce6 group, clinical score lower in the 0.1% Ce6 group at 1 day post PDI. These findings suggest that PDI with Ce6 and red light has a transient efficacy in killing MDR-PA in vivo, and repetitive PDI treatments are required to fully resolve the infection. Before its clinical application, the paradoxical bacterial regrowth post PDI has to be further studied.
authors.affiliation: Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany.|Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Ming-Feng
authors.initials: MF
authors.lastname: Wu
authors.affiliation: Institute for Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany.
authors.forename: Mona
authors.initials: M
authors.lastname: Deichelbohrer
authors.affiliation: Institute for Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Tschernig
authors.affiliation: Institute for Clinical &Experimental Surgery, Saarland University, Homburg/Saar, Germany.
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Laschke
authors.affiliation: Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany.|Department of Ophthalmology, Semmelweis University, Budapest, Hungary.
authors.forename: Nóra
authors.initials: N
authors.lastname: Szentmáry
authors.affiliation: ApocarePharma GmbH, Bielefeld, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Hüttenberger
authors.affiliation: Department of Physics, University of Kaiserslautern, Kaiserslautern, Germany.
authors.forename: Hans-Jochen
authors.initials: HJ
authors.lastname: Foth
authors.affiliation: Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany.
authors.forename: Berthold
authors.initials: B
authors.lastname: Seitz
authors.affiliation: Institute for Medical Microbiology and Hygiene, Saarland University, Homburg/Saar, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Bischoff
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D002735:Chlorophyllides; D060527:Corneal Keratocytes / Q000187:drug effects / Q000382:microbiology / Q000528:radiation effects; D018432:Drug Resistance, Multiple / Q000235:genetics / Q000528:radiation effects; D006801:Humans; D007634:Keratitis / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology / Q000532:radiotherapy; D008027:Light; D051379:Mice; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011166:Porphyrins / Q000008:administration & dosage*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity
chemical_list: D002735:Chlorophyllides; D017319:Photosensitizing Agents; D011166:Porphyrins; C062985:phytochlorin