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Romanowski EG, Mumper SM, Shanks HQ, Yates KA, Mandell JB, Zegans ME, Shanks RM. Cefiderocol Is an Effective Topical Monotherapy for Experimental Extensively Drug-Resistant Pseudomonas aeruginosa Keratitis. Ophthalmol Sci 2024; 4:100452. [PMID: 38560275 PMCID: PMC10973669 DOI: 10.1016/j.xops.2023.100452] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/30/2023] [Accepted: 12/04/2023] [Indexed: 04/04/2024]
Abstract
Purpose To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug-resistant (XDR) Pseudomonas aeruginosa keratitis. Design Preclinical study. Subjects and Controls Deidentified P. aeruginosa keratitis isolates, XDR P. aeruginosa from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.3%, and tobramycin 14 mg/ml. Methods Intervention or Testing Cefiderocol antibacterial activity against P. aeruginosa keratitis isolates (n = 135) was evaluated by minimum inhibitory concentration (MIC) testing. Ocular toxicity/tolerability and antibacterial efficacy were tested in vivo with experimental rabbit models. Corneal concentrations and stability were assessed using a bioassay. Main Outcome Measures Minimum inhibitory concentration analysis for susceptibility, graded tests for ocular toxicity/tolerability, colony-forming unit (CFU) analysis for bacterial burden, corneal cefiderocol concentrations. Results One hundred percent of P. aeruginosa keratitis isolates were susceptible to cefiderocol (n = 135), the MIC90 was 0.125 μg/ml including the XDR isolate (MIC = 0.125 μg/ml). Topical cefiderocol 50 mg/ml was minimally toxic to the ocular surface and was well tolerated. For the XDR P. aeruginosa isolate, topical cefiderocol 50 mg/ml, significantly decreased corneal CFU compared with ciprofloxacin 0.3%, tobramycin 14 mg/ml, and saline. In addition, tobramycin 14 mg/ml was more effective than the saline control. Mean cefiderocol corneal concentrations were 191× greater than the MIC90 of the P. aeruginosa keratitis isolates. Refrigerated cefiderocol maintained antimicrobial activity over a 1-month period. Conclusions These results demonstrate that cefiderocol is well tolerated on rabbit corneas and is effective against P. aeruginosa keratitis isolates in vitro and was effective in vivo against an XDR isolate in a rabbit keratitis model. Given the recent outbreak of keratitis caused by this XDR P. aeruginosa, cefiderocol is a promising additional antibiotic that should be further evaluated for topical treatment of keratitis caused by antibiotic resistant P. aeruginosa. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kathleen A. Yates
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jonathan B. Mandell
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Robert M.Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Romanowski EG, Brothers KM, Calvario RC, Stella NA, Kim T, Elsayed M, Kadouri DE, Shanks RMQ. Predatory bacteria prevent the proliferation of intraocular Serratia marcescens and fluoroquinolone-resistant Pseudomonas aeruginosa. Microbiology (Reading) 2024; 170:001433. [PMID: 38358321 PMCID: PMC10924457 DOI: 10.1099/mic.0.001433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 01/25/2024] [Indexed: 02/16/2024]
Abstract
Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus was evaluated in a New Zealand white rabbit endophthalmitis prevention model. Predatory bacteria Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus were able to reduce proliferation of keratitis isolates of P. aeruginosa and to a lesser extent S. marcescens. However, it was not able to significantly reduce the number of intraocular S. aureus, which is not a productive prey for these predatory bacteria, suggesting that the inhibitory effect on P. aeruginosa and S. marcescens requires active predation rather than an antimicrobial immune response. Similarly, UV-inactivated B. bacteriovorus were unable to prevent proliferation of P. aeruginosa. Together, these data indicate in vivo inhibition of Gram-negative bacteria proliferation within the intra-ocular environment by predatory bacteria.
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Affiliation(s)
- Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kimberly M. Brothers
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rachel C. Calvario
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nicholas A. Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tami Kim
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Mennat Elsayed
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Daniel E. Kadouri
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
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Shanks RMQ, Atta S, Stella NA, Sundar-Raj CV, Romanowski JE, Grewal AS, Shanks HQ, Mumper SM, Dhaliwal DK, Mammen A, Callaghan JD, Calvario RC, Romanowski EG, Kowalski RP, Zegans ME, Jhanji V. A rise in the frequency of lasR mutant Pseudomonas aeruginosa among keratitis isolates between 1993 and 2021. Front Cell Infect Microbiol 2023; 13:1286842. [PMID: 38029269 PMCID: PMC10651084 DOI: 10.3389/fcimb.2023.1286842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Pseudomonas aeruginosa causes vision threatening keratitis. The LasR transcription factor regulates virulence factors in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. P. aeruginosa isolates with lasR mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone. A previous study demonstrated 22% (n=101) of P. aeruginosa keratitis isolates from India between 2010 and 2016 were sheen positive lasR mutants, and the sheen phenotype correlated with worse clinical outcomes for patients. In this study, a longitudinal collection of P. aeruginosa keratitis isolates from Eastern North America were screened for lasR mutations by the sheen phenotype and sequencing of the lasR gene. Methods Keratitis isolates (n=399) were classified by sheen phenotype. The lasR gene was cloned from a subset of isolates, sequenced, and tested for loss of function or dominant-negative status based on an azocasein protease assay. A retrospective chart review compared outcomes of keratitis patients infected by sheen positive and negative isolates. Results A significant increase in sheen positive isolates was observed between 1993 and 2021. Extracellular protease activity was reduced among the sheen positive isolates and a defined lasR mutant. Cloned lasR alleles from the sheen positive isolates were loss of function or dominant negative and differed in sequence from previously reported ocular lasR mutant alleles. Retrospective analysis of patient information suggested significantly better visual outcomes for patients infected by sheen positive isolates. Discussion These results indicate an increase in lasR mutations among keratitis isolates in the United States and suggest that endemic lasR mutants can cause keratitis.
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Affiliation(s)
- Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sarah Atta
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Nicholas A. Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Chollapadi V. Sundar-Raj
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - John E. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Arman S. Grewal
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Deepinder K. Dhaliwal
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Alex Mammen
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jake D. Callaghan
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Rachel C. Calvario
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Regis P. Kowalski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
| | - Vishal Jhanji
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Romanowski EG, Brothers KM, Calvario RC, Stella NA, Kim T, Elsayed M, Kadouri DE, Shanks RMQ. Intra-ocular Predation of Fluoroquinolone-Resistant Pseudomonas aeruginosa and Serratia marcescens by Predatory Bacteria. bioRxiv 2023:2023.09.17.558130. [PMID: 37745563 PMCID: PMC10516018 DOI: 10.1101/2023.09.17.558130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus was evaluated in a New Zealand White rabbit endophthalmitis prevention model. Predatory bacteria Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus were able to reduce proliferation of keratitis isolates of P. aeruginosa and S. marcescens. However, it was not able to significantly reduce S. aureus, which is not a productive prey for these predatory bacteria, suggesting that the inhibitory effect on P. aeruginosa requires active predation rather than an antimicrobial immune response. Similarly, UV-inactivated B. bacteriovorus were unable to prevent proliferation of P. aeruginosa. Together, these data suggest in vivo predation of Gram-negative bacteria within the intra-ocular environment.
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Affiliation(s)
- Eric G Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA
| | - Kimberly M Brothers
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA
| | - Rachel C Calvario
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA
| | - Nicholas A Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA
| | - Tami Kim
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Mennat Elsayed
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Daniel E Kadouri
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Robert M Q Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA
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Romanowski EG, Mumper SM, Shanks HQ, Yates KA, Mandell JB, Zegans ME, Shanks RMQ. Cefiderocol is an effective topical monotherapy for experimental extensively-drug resistant Pseudomonas aeruginosa keratitis. bioRxiv 2023:2023.08.31.555778. [PMID: 37693441 PMCID: PMC10491197 DOI: 10.1101/2023.08.31.555778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Purpose To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug resistant (XDR) Pseudomonas aeruginosa keratitis. Design Preclinical study. Subjects and Controls Deidentified P. aeruginosa keratitis isolates, XDR P. aeruginosa from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.3%, and tobramycin 14 mg/ml. Methods Intervention or Testing Cefiderocol antibacterial activity against P. aeruginosa keratitis isolates (n=135) was evaluated by minimum inhibitory concentration (MIC) testing. Ocular toxicity/tolerability and antibacterial efficacy were tested in vivo with experimental rabbit models. Corneal concentrations and stability were assessed using a bioassay. Main Outcome Measures MIC analysis for susceptibility, graded tests for ocular toxicity/tolerability, CFU analysis for bacterial burden, corneal cefiderocol concentrations. Results 100% of P. aeruginosa keratitis isolates were susceptible to cefiderocol (n=135), the MIC90 was 0.125 μg/ml including the XDR isolate (MIC = 0.125 μg/ml). Topical cefiderocol 50 mg/ml was minimally toxic to the ocular surface and was well tolerated. For the XDR P. aeruginosa isolate, topical cefiderocol 50 mg/ml, significantly decreased corneal CFU compared to ciprofloxacin 0.3%, tobramycin 14 mg/ml, and saline. In addition, tobramycin 14 mg/ml was more effective than the saline control. Mean cefiderocol corneal concentrations were 191x greater than the MIC90 of the P. aeruginosa keratitis isolates. Refrigerated cefiderocol maintained antimicrobial activity over a one-month period. Conclusions These results demonstrate that cefiderocol is well tolerated on rabbit corneas and is effective against P. aeruginosa keratitis isolates in vitro and was effective in vivo against an XDR isolate in a rabbit keratitis model. Given the recent outbreak of keratitis caused by this XDR P. aeruginosa, cefiderocol is a promising additional antibiotic that should be further evaluated for topical treatment of keratitis caused by antibiotic resistant P. aeruginosa.
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Affiliation(s)
- Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kathleen A. Yates
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jonathan B. Mandell
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Shanks RMQ, Atta S, Stella NA, Sundar-Raj CV, Romanowski JE, Grewel AS, Shanks HQ, Mumper SM, Dhaliwal DK, Mammen A, Callaghan JD, Calvario RC, Romanowski EG, Kowalski RP, Zegans ME, Jhanji V. Rise in frequency of lasR mutant Pseudomonas aeruginosa among keratitis isolates between 1993 and 2021. bioRxiv 2023:2023.08.22.554354. [PMID: 37662319 PMCID: PMC10473646 DOI: 10.1101/2023.08.22.554354] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Pseudomonas aeruginosa causes severe vision threatening keratitis. LasR is a transcription factor that regulates virulence associated genes in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. P. aeruginosa isolates with lasR mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone. A previous study indicated a high proportion (22 out of 101) of P. aeruginosa keratitis isolates from India between 2010 and 2016 were sheen positive and had mutations in the lasR gene, and the sheen phenotype correlated with worse clinical outcomes for patients. In this study, a longitudinal collection of P. aeruginosa keratitis isolates from Eastern North America were screened for lasR mutations by the sheen phenotype and sequencing of the lasR gene. A significant increase in the frequency of isolates with the sheen positive phenotype was observed in isolates between 1993 and 2021. Extracellular protease activity was lower among the sheen positive isolates and a defined lasR mutant. Cloned lasR alleles from the sheen positive isolates were loss of function or dominant negative and differed in sequence from previously reported ocular lasR mutant alleles. Insertion elements were present in a subset of independent isolates and may represent an endemic source from some of the isolates. Retrospective analysis of patient information suggested significantly better visual outcomes for patients with infected by sheen positive isolates. Together, these results indicate an increasing trend towards lasR mutations among keratitis isolates at a tertiary eye care hospital in the United States.
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Affiliation(s)
- Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah Atta
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Nicholas A. Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chollapadi V. Sundar-Raj
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - John E. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Arman S. Grewel
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Deepinder K. Dhaliwal
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Alex Mammen
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jake D. Callaghan
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rachel C. Calvario
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Regis P. Kowalski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Vishal Jhanji
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Romanowski EG, Yates KA, Gordon YJ. Cyclopentenylcytosine (CPE-C): In Vitro and In Vivo Evaluation as an Antiviral against Adenoviral Ocular Infections. Molecules 2023; 28:5078. [PMID: 37446740 DOI: 10.3390/molecules28135078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/13/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
Adenoviruses are the major cause of ocular viral infections worldwide. Currently, there is no approved antiviral treatment for these eye infections. Cyclopentenylcytosine (CPE-C) is an antiviral that has demonstrated activity against more than 20 viruses. The goals of the current study were to determine the in vitro and in vivo antiviral activity of CPE-C as well as its ocular toxicity. Antiviral activity was evaluated in vitro using standard plaque reduction assays to determine the 50% effective concentrations (EC50s) and in vivo in the Ad5/NZW rabbit ocular replication model. Ocular toxicity was determined in uninfected rabbit eyes following topical ocular application. The in vitro EC50s for CPE-C ranged from 0.03 to 0.059 μg/mL for nine adenovirus types that commonly infect the eye. Ocular toxicity testing determined CPE-C to be non-irritating or practically non-irritating by Draize scoring. In vivo, 3% CPE-C topically administered 4X or 2X daily for 7 days to adenovirus-infected eyes demonstrated effective antiviral activity compared with the negative control and comparable antiviral activity to the positive control, 0.5% cidofovir, topically administered twice daily for 7 days. We conclude CPE-C was relatively non-toxic to rabbit eyes and demonstrated potent anti-adenoviral activity in vitro and in vivo.
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Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Vision Institute, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Kathleen A Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Vision Institute, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Y Jerold Gordon
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Vision Institute, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
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8
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Shanks RMQ, Romanowski EG, Romanowski JE, Davoli K, McNamara NA, Klarlund JK. Extending the use of biologics to mucous membranes by attachment of a binding domain. Commun Biol 2023; 6:477. [PMID: 37130912 PMCID: PMC10154311 DOI: 10.1038/s42003-023-04801-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 04/03/2023] [Indexed: 05/04/2023] Open
Abstract
Biologics are almost exclusively administered systemically, but localized delivery is preferable as it minimizes off-target exposure and allows more aggressive treatments. Topical application of biologics to epithelia is generally ineffective because most are covered with fluids and biologics are washed out too quickly to have significant therapeutic effects. Here we explore the idea that attaching a binding domain can serve as an "anchor" to extend the residency time of biologics on wet epithelia, allowing their effective use even with infrequent applications. We use topical application to the ocular surface as a challenging test since foreign substances are washed out especially efficiently by tear flow and blinking. Our results demonstrate that conjugation of antibodies to wheat germ agglutinin, which binds GlcNAc and sialic acid that are ubiquitously present in tissues, increases their half-life 350-fold upon application to the ocular surface in a mouse model of dry eye, a common and onerous disease in humans. Importantly, antibodies to IL-17A, IL-23, and IL-1β conjugated to the agglutinin reduces manifestations of dry eye, even when applied just once daily. In contrast, unconjugated antibodies are ineffective. Attaching an anchor to biologics is a simple means to overcome washout and to extend their therapeutic use.
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Affiliation(s)
- Robert M Q Shanks
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eric G Romanowski
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - John E Romanowski
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Katherine Davoli
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nancy A McNamara
- School of Optometry and Vision Science Graduate Program, University of California, Berkeley, CA, USA
| | - Jes K Klarlund
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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Romanowski EG, Stella NA, Brazile BL, Lathrop KL, Franks JM, Sigal IA, Kim T, Elsayed M, Kadouri DE, Shanks RMQ. Predatory bacteria can reduce Pseudomonas aeruginosa induced corneal perforation and proliferation in a rabbit keratitis model. Ocul Surf 2023; 28:254-261. [PMID: 37146902 DOI: 10.1016/j.jtos.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/17/2023] [Accepted: 05/02/2023] [Indexed: 05/07/2023]
Abstract
PURPOSE Pseudomonas aeruginosa keratitis is a severe ocular infection that can lead to perforation of the cornea. In this study we evaluated the role of bacterial quorum sensing in generating corneal perforation and bacterial proliferation and tested whether co-injection of the predatory bacteria Bdellovibrio bacteriovorus could alter the clinical outcome. P. aeruginosa with lasR mutations were observed among keratitis isolates from a study collecting samples from India, so an isogenic lasR mutant strain of P. aeruginosa was included. METHODS Rabbit corneas were intracorneally infected with P. aeruginosa strain PA14 or an isogenic ΔlasR mutant and co-injected with PBS or B. bacteriovorus. After 24 h, eyes were evaluated for clinical signs of infection. Samples were analyzed by scanning electron microscopy, optical coherence tomography, sectioned for histology, and corneas were homogenized for CFU enumeration and for inflammatory cytokines. RESULTS We observed that 54% of corneas infected by wild-type PA14 presented with a corneal perforation (n = 24), whereas only 4% of PA14 infected corneas that were co-infected with B. bacteriovorus perforate (n = 25). Wild-type P. aeruginosa proliferation was reduced 7-fold in the predatory bacteria treated eyes. The ΔlasR mutant was less able to proliferate compared to the wild-type, but was largely unaffected by B. bacteriovorus. CONCLUSION These studies indicate a role for bacterial quorum sensing in the ability of P. aeruginosa to proliferate and cause perforation of the rabbit cornea. Additionally, this study suggests that predatory bacteria can reduce the virulence of P. aeruginosa in an ocular prophylaxis model.
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Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nicholas A Stella
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Bryn L Brazile
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kira L Lathrop
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jonathan M Franks
- Center for Biological Imaging, University of Pittsburgh School of Engineering, Pittsburgh, PA, USA
| | - Ian A Sigal
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Bioengineering, Swanson School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tami Kim
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Mennat Elsayed
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Daniel E Kadouri
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ, USA
| | - Robert M Q Shanks
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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Romanowski EG, Stella NA, Brazile BL, Lathrop KL, Franks J, Sigal IA, Kim T, Elsayed M, Kadouri DE, Shanks RM. Predatory Bacteria can Reduce Pseudomonas aeruginosa Induced Corneal Perforation and Proliferation in a Rabbit Keratitis Model. bioRxiv 2023:2023.03.15.532777. [PMID: 36993476 PMCID: PMC10055036 DOI: 10.1101/2023.03.15.532777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Purpose Pseudomonas aeruginosa keratitis is a severe ocular infection that can lead to perforation of the cornea. In this study we evaluated the role of bacterial quorum sensing in generating corneal perforation and bacterial proliferation and tested whether co-injection of the predatory bacteria Bdellovibrio bacteriovorus could alter the clinical outcome. P. aeruginosa with lasR mutations were observed among keratitis isolates from a study collecting samples from India, so an isogenic lasR mutant strain of P. aeruginosa was included. Methods Rabbit corneas were intracorneally infected with P. aeruginosa strain PA14 or an isogenic Δ lasR mutant and co-injected with PBS or B. bacteriovorus . After 24 h, eyes were evaluated for clinical signs of infection. Samples were analyzed by scanning electron microscopy, optical coherence tomography, sectioned for histology, and corneas were homogenized for CFU enumeration and for inflammatory cytokines. Results We observed that 54% of corneas infected by wild-type PA14 presented with a corneal perforation (n=24), whereas only 4% of PA14 infected corneas that were co-infected with B. bacteriovorus perforate (n=25). Wild-type P. aeruginosa proliferation was reduced 7-fold in the predatory bacteria treated eyes. The Δ lasR mutant was less able to proliferate compared to the wild-type, but was largely unaffected by B. bacteriovorus . Conclusion These studies indicate a role for bacterial quorum sensing in the ability of P. aeruginosa to proliferate and cause perforation of the rabbit cornea. Additionally, this study suggests that predatory bacteria can reduce the virulence of P. aeruginosa in an ocular prophylaxis model.
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Affiliation(s)
- Eric G. Romanowski
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Nicholas A. Stella
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Bryn L. Brazile
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Kira L. Lathrop
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Center for Biological Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Jonathan Franks
- Center for Biological Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Ian A. Sigal
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Bioengineering, Swanson School of Medicine, University of Pittsburgh, Pittsburgh PA
| | - Tami Kim
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Mennat Elsayed
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Daniel E. Kadouri
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ
| | - Robert M.Q. Shanks
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Sherry B, Lee S, Ramos Cadena MDLA, Laynor G, Patel SR, Simon MD, Romanowski EG, Hochman SE, Schuman JS, Prescott C, Thiel CL. How Ophthalmologists Can Decarbonize Eye Care: A Review of Existing Sustainability Strategies and Steps Ophthalmologists Can Take. Ophthalmology 2023:S0161-6420(23)00137-9. [PMID: 36889466 DOI: 10.1016/j.ophtha.2023.02.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/13/2023] [Accepted: 02/27/2023] [Indexed: 03/08/2023] Open
Abstract
TOPIC Understanding approaches to sustainability in cataract surgery and their risks and benefits CLINICAL RELEVANCE: In the United States, healthcare is responsible for approximately 8.5% of greenhouse gas (GHG), and cataract surgery is one of the most commonly performed surgical procedures. Ophthalmologists can contribute to reducing GHG emissions, which lead to a steadily increasing list of health concerns ranging from trauma to food instability. METHODS We conducted a literature review to identify the benefits and risks of sustainability interventions. We then organized these interventions into a decision tree for use by individual surgeons. RESULTS Identified sustainability interventions fall into the domains of advocacy and education, pharmaceuticals, process, and supplies and waste. Existing literature shows certain interventions may be safe, cost-effective, and environmentally friendly. These include dispensing medications home to patients after surgery, multi-dosing appropriate medications, training staff to properly sort medical waste, reducing the number of supplies used during surgery, and implementing immediate sequential bilateral cataract surgery where clinically appropriate. The literature was lacking on the benefits or risks for some interventions, such as switching specific single use supplies to reusables or implementing a hub-and-spoke style theatre setup. Many of the advocacy and education interventions have inadequate literature specific to ophthalmology but are likely to have minimal risks. CONCLUSIONS Ophthalmologists can engage in a variety of safe and effective approaches to reduce or eliminate dangerous GHG emissions associated with cataract surgery.
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Affiliation(s)
| | - Samuel Lee
- NYU Langone Health, NYU Langone Hospitals
| | | | | | | | | | - Eric G Romanowski
- Research Director of The Charles T. Campbell Ophthalmic Microbiology Laboratory; Research Instructor of Ophthalmology, Department of Ophthalmology University of Pittsburgh School of Medicine Pittsburgh, PA
| | - Sarah E Hochman
- Assistant Professor, Department of Medicine, Division of Infectious Diseases and Immunology, NYU Grossman School of Medicine
| | | | - Christina Prescott
- Residency Program Director; Vice Chair for Education; Director of the Cornea Service; Department of Ophthalmology, NYU Langone Health, New York University, New York, New York, 10017, USA
| | - Cassandra L Thiel
- Assistant Professor Department of Population Health, NYU Grossman School of Medicine.
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12
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Romanowski EG, Yates KA, Romanowski JE, Shanks RMQ, Kowalski RP. The in vitro Evaluation of the Activity of COVID-19 Antiviral Drugs Against Adenovirus. Clin Ophthalmol 2022; 15:4787-4793. [PMID: 35221670 PMCID: PMC8866980 DOI: 10.2147/opth.s340576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/03/2021] [Indexed: 12/02/2022] Open
Abstract
Purpose Presently, there is no approved antiviral therapy for adenovirus (HAdV) ocular infections. During the COVID-19 pandemic, increased attention has been focused on antiviral treatments. Remdesivir, hydroxychloroquine, ivermectin, and umifenovir (Arbidol) have been touted as potential antiviral treatments for COVID-19. The goal of the current study was to determine whether these potential COVID-19 antivirals produce in vitro antiviral activity against a panel of ocular adenovirus types. Methods The 50% effective concentrations (EC50) of remdesivir (REM), hydroxychloroquine (HCQ), ivermectin (IVM), umifenovir (UMF) and cidofovir (CDV) (positive antiviral control) were determined for the human HAdV types HAdV3, HAdV4, HAdV5, HAdV7a, HAdV8, HAdV19/64 and HAdV37 using standard plaque-reduction assays in A549 cells. Results The range of mean in vitro EC50 concentrations for each antiviral across the range of HAdV types is as follows: The positive antiviral control, CDV, ranged from 0.47 to 9.62 µM; REM ranged from 0.21 to 11.27 µM; UMF ranged from 3.72 to 64.8 µM; IVR ranged from 2.60 to 201.3 µM; and HCQ was >10 µM for all Ad types because of toxicity to the A549 cells. REM produced lower EC50 concentrations than CDV for 6 of 7 HAdV types. Potency increases with lower EC50 concentrations. Conclusion REM demonstrated anti-adenovirus activity in a range similar to that demonstrated by cidofovir. UMF and IVR demonstrated larger ranges of antiviral activity than CDV and REM across the panel of HAdV types. The anti-adenovirus activity of HCQ could not be determined due to cytotoxicity. Further investigation of REM, UMF, and IVR as antivirals for adenovirus is indicated.
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Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kathleen A Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - John E Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Robert M Q Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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13
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Kowalski RP, Nayyar SV, Romanowski EG, Jhanji V. Anti-Infective Treatment and Resistance Is Rarely Problematic with Eye Infections. Antibiotics (Basel) 2022; 11:antibiotics11020204. [PMID: 35203807 PMCID: PMC8868068 DOI: 10.3390/antibiotics11020204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 11/16/2022] Open
Abstract
The treatment of eye infections is very different than treating other body infections that require systemic anti-infectives. Endophthalmitis, keratitis, conjunctivitis, and other ocular infections are treated with direct injection and with topical drops directly to the infection site. There are no anti-infective susceptibility standards to interpret treatment success, but the systemic standards can be used to guide ocular therapy if the concentration of anti-infective in the ocular tissue is assumed to be higher than the concentration in the blood serum. This Perspective describes: (1) eye infections, (2) diagnostics of eye infections, (3) anti-infective treatment of eye infections, (4) anti-infective resistance of ocular pathogens, and (5) alternative anti-infective delivery and therapy. The data, based on years of clinical and laboratory research, support the premise that ocular infections are less problematic if etiologic agents are laboratory-diagnosed and if prompt, potent, anti-infective therapy is applied. Anti-infective susceptibility should be monitored to assure continued therapeutic success and the possibility of new-found resistance. New delivery systems and therapies may be helpful to better treat future ocular infections.
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Affiliation(s)
- Regis P. Kowalski
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
- Correspondence: ; Tel.: +1-412-647-7211
| | - Shannon V. Nayyar
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
| | - Eric G. Romanowski
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
| | - Vishal Jhanji
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
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Romanowski EG, Yadav S, Stella NA, Yates KA, Romanowski JE, Dhaliwal DK, Shanks RMQ. Bacterial Keratitis: Similar Bacterial and Clinical Outcomes in Female versus Male New Zealand White Rabbits Infected with Serratia marcescens. Curr Eye Res 2021; 47:505-510. [PMID: 34854780 DOI: 10.1080/02713683.2021.2013897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE Females and males respond differently to a number of systemic viral infections. Differences between females and males with respect to the severity of keratitis caused by Gram-negative bacteria such as Serratia marcescens are less well established. METHODS In this study, we injected female and male New Zealand White rabbit corneas with a keratitis isolate of S. marcescens and evaluated the eyes after 48 hours for a number of clinical and microbiological parameters. RESULTS No statistical differences in bacterial burden and corneal scores were recorded between female and male rabbits although there was a non-significant trend toward a higher frequency of female rabbits demonstrating hypopyons. CONCLUSIONS This data suggests that for experimental bacterial keratitis studies involving Gram-negative rods, a single sex or mixed group of rabbit is sufficient for evaluating pathology and bacterial burdens. This will reduce the number of animals used for subsequent studies.
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Affiliation(s)
- Eric G Romanowski
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Sanya Yadav
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Nicholas A Stella
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kathleen A Yates
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - John E Romanowski
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Deepinder K Dhaliwal
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Robert M Q Shanks
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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15
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Kuang L, Ross AE, Kanu LN, Romanowski EG, Kowalski RP, Kohane DS, Ciolino JB. A novel, sensitive, and widely accessible besifloxacin quantification method by HPLC-fluorescence: Application to an ocular pharmacokinetic study. J Chromatogr B Analyt Technol Biomed Life Sci 2021; 1185:123010. [PMID: 34731742 DOI: 10.1016/j.jchromb.2021.123010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 10/04/2021] [Accepted: 10/24/2021] [Indexed: 02/03/2023]
Abstract
Besifloxacin has been embraced for the treatment of ocular bacterial infections. While LC-MS/MS has been used in investigating BSF pharmacokinetics, those costly instruments are not universally available and have complicated requirements for operation and maintenance. Additionally, pharmacokinetics of besifloxacin in dose-intense regimens are still unknown. Herein, a new quantification method was developed employing the widely accessible HPLC with fluorescence detection and applied to an ocular pharmacokinetic study with an intense regimen. Biosamples were pre-treated using protein precipitation. Chromatographic separation was achieved on a C18 column using mobile phase of 0.1% trifluoroacetic acid and acetonitrile. To address the weak fluorescence issue of besifloxacin, effects of detection parameters, elution pattern, pH of mobile phase, and reconstitution solvents were investigated. The method was fully validated per US-FDA guidelines and demonstrated precision (<13%), accuracy (91-112%), lower limit of quantification (5 ng/mL), linearity over clinically relevant concentrations (R2 > 0.999), matrix-effects (93-105%), recoveries (95-106%), and excellent selectivity. The method showed agreement with agar disk diffusion assays for in vitro screening and comparable in vivo performance to LC-MS/MS (Deming Regression, y = 1.010x + 0.123, r = 0.997; Bland-Altman analysis, mean difference was -6.3%; n = 21). Pharmacokinetic parameters suggested superior surface-retentive properties of besifloxacin. Maximum concentrations were 1412 ± 1910 and 0.15 ± 0.12 μg/mL; area under the curve was 1,637 and 1.08 µg·h/g; and half-life was 4.9 and 4.1 h; and pharmacokinetic-to-pharmacodynamic ratios were ≥ 409 and ≤ 17.8 against ocular pathogens in tears and aqueous humor, respectively. This readily available method is sensitive for biosamples and practical for routine use, facilitating besifloxacin therapy development.
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Affiliation(s)
- Liangju Kuang
- Schepens Eye Research Institute of Massachusetts Eye & Ear, Dept. of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Amy E Ross
- Schepens Eye Research Institute of Massachusetts Eye & Ear, Dept. of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Levi N Kanu
- Schepens Eye Research Institute of Massachusetts Eye & Ear, Dept. of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Daniel S Kohane
- Laboratory for Biomaterials and Drug Delivery, Dept. of Anesthesiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
| | - Joseph B Ciolino
- Schepens Eye Research Institute of Massachusetts Eye & Ear, Dept. of Ophthalmology, Harvard Medical School, Boston, MA, United States.
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16
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Kowalski R, Kamyar R, Rhee M, Mammen A, Dhaliwal D, Romanowski EG, Jhanji V, Eller AW. The Antibacterial Comparison of 5% and 2.5% Povidone Iodine to 0.01% Hypochlorous Acid Using Corneoscleral Tissue as a Solid-Phase Medium. Clin Ophthalmol 2021; 15:3697-3704. [PMID: 34511873 PMCID: PMC8420804 DOI: 10.2147/opth.s328696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/23/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose Prophylactic topical antiseptics used to eliminate bacteria on the ocular surface prior to ocular surgery should be both effective and non-irritating. Five percent povidone iodine (PI) is an accepted antiseptic used for prophylaxis. Dilute 2.5% PI and 0.01% hypochlorous acid (HOCl) may be more patient comfortable and equally effective. PI at 5% and 2.5% were compared to HOCl against a battery of bacterial endophthalmitis isolates using corneoscleral tissue as a solid-phase medium to determine antiseptic efficacy. Methods Bacteria from 20 cases of endophthalmitis were tested for the elimination of growth against topical 5% PI, 2.5% PI, HOCl, and no antiseptic using donor corneoscleral tissue. The tissue was inoculated with 103 colony forming units of bacteria prior to a 3-minute contact time with the antiseptics, placed in liquid growth medium, and monitored for growth at three days. No growth indicated antiseptic treatment success. Differences were analyzed using Chi square (χ2). Results For 20 isolates, 5% PI was comparable to 2.5% PI for preventing bacteria growth (p=0.71), and both were more effective than HOCl (p=0.004). Estimated weighted comparison over a 27-year period indicated that for all bacterial groups, except Streptococcus viridans, 5% PI was equally effective to 2.5% PI for preventing bacterial growth (p=1.0). For Streptococcus viridans, 5% PI was more effective than 2.5% PI (p=0.0001). Both concentrations of PI were more effective than HOCl (p=0.00001). Conclusion Five percent PI appears to be optimal as a prophylaxis prior to ocular surgery.
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Affiliation(s)
- Regis Kowalski
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Roheena Kamyar
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Michelle Rhee
- The Eye-Bank for Sight Restoration, New York, NY, USA
| | - Alex Mammen
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Deepinder Dhaliwal
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric G Romanowski
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Vishal Jhanji
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Andrew W Eller
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Harshaw NS, Stella NA, Lehner KM, Romanowski EG, Kowalski RP, Shanks RMQ. Antibiotics Used in Empiric Treatment of Ocular Infections Trigger the Bacterial Rcs Stress Response System Independent of Antibiotic Susceptibility. Antibiotics (Basel) 2021; 10:antibiotics10091033. [PMID: 34572615 PMCID: PMC8470065 DOI: 10.3390/antibiotics10091033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/18/2021] [Accepted: 08/21/2021] [Indexed: 12/02/2022] Open
Abstract
The Rcs phosphorelay is a bacterial stress response system that responds to envelope stresses and in turn controls several virulence-associated pathways, including capsule, flagella, and toxin biosynthesis, of numerous bacterial species. The Rcs system also affects antibiotic tolerance, biofilm formation, and horizontal gene transfer. The Rcs system of the ocular bacterial pathogen Serratia marcescens was recently demonstrated to influence ocular pathogenesis in a rabbit model of keratitis, with Rcs-defective mutants causing greater pathology and Rcs-activated strains demonstrating reduced inflammation. The Rcs system is activated by a variety of insults, including β-lactam antibiotics and polymyxin B. In this study, we developed three luminescence-based transcriptional reporters for Rcs system activity and used them to test whether antibiotics used for empiric treatment of ocular infections influence Rcs system activity in a keratitis isolate of S. marcescens. These included antibiotics to which the bacteria were susceptible and resistant. Results indicate that cefazolin, ceftazidime, polymyxin B, and vancomycin activate the Rcs system to varying degrees in an RcsB-dependent manner, whereas ciprofloxacin and tobramycin activated the promoter fusions, but in an Rcs-independent manner. Although minimum inhibitory concentration (MIC) analysis demonstrated resistance of the test bacteria to polymyxin B and vancomycin, the Rcs system was activated by sub-inhibitory concentrations of these antibiotics. Together, these data indicate that a bacterial stress system that influences numerous pathogenic phenotypes and drug-tolerance is influenced by different classes of antibiotics despite the susceptibility status of the bacterium.
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18
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Romanowski JE, Nayyar SV, Romanowski EG, Jhanji V, Shanks RMQ, Kowalski RP. Speciation and Antibiotic Susceptibilities of Coagulase Negative Staphylococci Isolated from Ocular Infections. Antibiotics (Basel) 2021; 10:antibiotics10060721. [PMID: 34208455 PMCID: PMC8234609 DOI: 10.3390/antibiotics10060721] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/07/2021] [Accepted: 06/10/2021] [Indexed: 11/16/2022] Open
Abstract
Coagulase-negative staphylococci (CoNS) are frequently occurring ocular opportunistic pathogens that are not easily identifiable to the species level. The goal of this study was to speciate CoNS and document antibiotic susceptibilities from cases of endophthalmitis (n = 50), keratitis (n = 50), and conjunctivitis/blepharitis (n = 50) for empiric therapy. All 150 isolates of CoNS were speciated using (1) API Staph (biochemical system), (2) Biolog GEN III Microplates (phenotypic substrate system), and (3) DNA sequencing of the sodA gene. Disk diffusion antibiotic susceptibilities for topical and intravitreal treatment were determined based on serum standards. CoNS identification to the species level by all three methods indicated that S. epidermidis was the predominant species of CoNS isolated from cases of endophthalmitis (84-90%), keratitis (80-86%), and conjunctivitis/blepharitis (62-68%). Identifications indicated different distributions of CoNS species among endophthalmitis (6), keratitis (10), and conjunctivitis/blepharitis (13). Antibiotic susceptibility profiles support empiric treatment of endophthalmitis with vancomycin, and keratitis treatment with cefazolin or vancomycin. There was no clear antibiotic choice for conjunctivitis/blepharitis. S. epidermidis was the most frequently found CoNS ocular pathogen, and infection by other CoNS appears to be less specific and random. Antibiotic resistance does not appear to be a serious problem associated with CoNS.
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Romanowski EG, Yates KA, Paull JRA, Heery GP, Shanks RMQ. Topical Astodrimer Sodium, a Non-Toxic Polyanionic Dendrimer, Demonstrates Antiviral Activity in an Experimental Ocular Adenovirus Infection Model. Molecules 2021; 26:molecules26113419. [PMID: 34198721 PMCID: PMC8201124 DOI: 10.3390/molecules26113419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 05/28/2021] [Accepted: 06/01/2021] [Indexed: 11/16/2022] Open
Abstract
There is no approved antiviral therapy for adenovirus (HAdV) ocular infections. Astodrimer sodium (SPL7013) is a polyanionic dendrimer with antiviral activity. The current study evaluated the ocular tolerability and anti-adenoviral efficacy of topical SPL7013 in rabbit ocular models. In a tolerability study, rabbits were treated with 3% SPL7013, vehicle, or 0.5% cidofovir. Their eyes were graded using the Draize scale. In antiviral efficacy studies, HAdV5 inoculated eyes were treated with 3% SPL7013, vehicle, or 0.5% cidofovir. Eyes were cultured for the virus on days 0, 1, 3, 4, 5, 7, 9, 11, and 14. Viral titers were determined. There were no differences in Draize scores between 3% SPL7013 and vehicle on any day. Cidofovir produced significantly higher Draize scores on day 12 than SPL7013 and vehicle. The 3% SPL7013 and 0.5% cidofovir significantly reduced daily viral titers and positive cultures per total compared with vehicle on several different days. The 3% SPL7013 and 0.5% cidofovir significantly reduced the duration of HAdV5 shedding compared to vehicle. The 3% SPL7013 demonstrated significantly more antiviral activity compared with vehicle in the Ad5/NZW rabbit ocular model. The 3% SPL7013 induced “minimal” to “practically non-irritating” Draize scores in the ocular tolerability study. Further development of astodrimer sodium as a topical antiviral therapy for adenoviral ocular infections is indicated.
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Affiliation(s)
- Eric G. Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.)
- Correspondence: ; Tel.: +1-412-647-2245
| | - Kathleen A. Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.)
| | - Jeremy R. A. Paull
- Starpharma Pty Ltd., 4-6 Southampton Crescent, Abbotsford, VIC 3067, Australia; (J.R.A.P.); (G.P.H.)
| | - Graham P. Heery
- Starpharma Pty Ltd., 4-6 Southampton Crescent, Abbotsford, VIC 3067, Australia; (J.R.A.P.); (G.P.H.)
| | - Robert M. Q. Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.)
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Romanowski EG, Hussein ITM, Cardinale SC, Butler MM, Morin LR, Bowlin TL, Yates KA, Shanks RMQ, Kowalski RP. Filociclovir Is an Active Antiviral Agent against Ocular Adenovirus Isolates In Vitro and in the Ad5/NZW Rabbit Ocular Model. Pharmaceuticals (Basel) 2021; 14:ph14040294. [PMID: 33810229 PMCID: PMC8066960 DOI: 10.3390/ph14040294] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/19/2021] [Accepted: 03/24/2021] [Indexed: 01/12/2023] Open
Abstract
Presently, there is no FDA- or EMA-approved antiviral for the treatment of human adenovirus (HAdV) ocular infections. This study determined the antiviral activity of filociclovir (FCV) against ocular HAdV isolates in vitro and in the Ad5/NZW rabbit ocular model. The 50% effective concentrations (EC50) of FCV and cidofovir (CDV) were determined for several ocular HAdV types using standard plaque reduction assays. Rabbits were topically inoculated in both eyes with HAdV5. On day 1, the rabbits were divided into four topical treatment groups: (1) 0.5% FCV 4x/day × 10 d; (2) 0.1% FCV 4x/day × 10 d; (3) 0.5% CDV 2x/day × 7 d; (4) vehicle 4x/day × 10 d. Eyes were cultured for virus on days 0, 1, 3, 4, 5, 7, 9, 11, and 14. The resulting viral eye titers were determined using standard plaque assays. The mean in vitro EC50 for FCV against tested HAdV types ranged from 0.50 to 4.68 µM, whereas those treated with CDV ranged from 0.49 to 30.3 µM. In vivo, compared to vehicle, 0.5% FCV, 0.1% FCV, and 0.5% CDV produced lower eye titers, fewer numbers of positive eye cultures, and shorter durations of eye infection. FCV demonstrated anti-adenovirus activity in vitro and in vivo.
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Affiliation(s)
- Eric G. Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.); (R.P.K.)
- Correspondence: ; Tel.: +1-412-647-2245
| | - Islam T. M. Hussein
- Microbiotix, Inc., Worcester, MA 01605, USA; (I.T.M.H.); (S.C.C.); (M.M.B.); (L.R.M.); (T.L.B.)
| | - Steven C. Cardinale
- Microbiotix, Inc., Worcester, MA 01605, USA; (I.T.M.H.); (S.C.C.); (M.M.B.); (L.R.M.); (T.L.B.)
| | - Michelle M. Butler
- Microbiotix, Inc., Worcester, MA 01605, USA; (I.T.M.H.); (S.C.C.); (M.M.B.); (L.R.M.); (T.L.B.)
| | - Lucas R. Morin
- Microbiotix, Inc., Worcester, MA 01605, USA; (I.T.M.H.); (S.C.C.); (M.M.B.); (L.R.M.); (T.L.B.)
| | - Terry L. Bowlin
- Microbiotix, Inc., Worcester, MA 01605, USA; (I.T.M.H.); (S.C.C.); (M.M.B.); (L.R.M.); (T.L.B.)
| | - Kathleen A. Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.); (R.P.K.)
| | - Robert M. Q. Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.); (R.P.K.)
| | - Regis P. Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; (K.A.Y.); (R.M.Q.S.); (R.P.K.)
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Galante AJ, Haghanifar S, Romanowski EG, Shanks RMQ, Leu PW. Correction to Superhemophobic and Antivirofouling Coating for Mechanically Durable and Wash-Stable Medical Textiles. ACS Appl Mater Interfaces 2020; 12:30016. [PMID: 32568502 DOI: 10.1021/acsami.0c08966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
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Galante AJ, Haghanifar S, Romanowski EG, Shanks RMQ, Leu PW. Superhemophobic and Antivirofouling Coating for Mechanically Durable and Wash-Stable Medical Textiles. ACS Appl Mater Interfaces 2020; 12:22120-22128. [PMID: 32320200 DOI: 10.1021/acsami.9b23058] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Medical textiles have a need for repellency to body fluids such as blood, urine, or sweat that may contain infectious vectors that contaminate surfaces and spread to other individuals. Similarly, viral repellency has yet to be demonstrated and long-term mechanical durability is a major challenge. In this work, we demonstrate a simple, durable, and scalable coating on nonwoven polypropylene textile that is both superhemophobic and antivirofouling. The treatment consists of polytetrafluoroethylene (PTFE) nanoparticles in a solvent thermally sintered to polypropylene (PP) microfibers, which creates a robust, low-surface-energy, multilayer, and multilength scale rough surface. The treated textiles demonstrate a static contact angle of 158.3 ± 2.6° and hysteresis of 4.7 ± 1.7° for fetal bovine serum and reduce serum protein adhesion by 89.7 ± 7.3% (0.99 log). The coated textiles reduce the attachment of adenovirus type 4 and 7a virions by 99.2 ± 0.2% and 97.6 ± 0.1% (2.10 and 1.62 log), respectively, compared to noncoated controls. The treated textiles provide these repellencies by maintaining a Cassie-Baxter state of wetting where the surface area in contact with liquids is reduced by an estimated 350 times (2.54 log) compared to control textiles. Moreover, the treated textiles exhibit unprecedented mechanical durability, maintaining their liquid, protein, and viral repellency after extensive and harsh abrasion and washing. The multilayer, multilength scale roughness provides for mechanical durability through self-similarity, and the samples have high-pressure stability with a breakthrough pressure of about 255 kPa. These properties highlight the potential of durable, repellent coatings for medical gowning, scrubs, or other hygiene textile applications.
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Affiliation(s)
- Anthony J Galante
- Department of Industrial Engineering, University of Pittsburgh, 3700 O'Hara, Benedum Hall, Pittsburgh, Pennsylvania 15261, United States
| | - Sajad Haghanifar
- Department of Industrial Engineering, University of Pittsburgh, 3700 O'Hara, Benedum Hall, Pittsburgh, Pennsylvania 15261, United States
| | - Eric G Romanowski
- Department of Ophthalmology, Charles T. Campbell Laboratory for Ophthalmic Microbiology, University of Pittsburgh School of Medicine, 203 Lothrop Street, Pittsburgh, Pennsylvania 15213, United States
| | - Robert M Q Shanks
- Department of Ophthalmology, Charles T. Campbell Laboratory for Ophthalmic Microbiology, University of Pittsburgh School of Medicine, 203 Lothrop Street, Pittsburgh, Pennsylvania 15213, United States
| | - Paul W Leu
- Department of Industrial Engineering, University of Pittsburgh, 3700 O'Hara, Benedum Hall, Pittsburgh, Pennsylvania 15261, United States
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Romanowski EG, Lehner KM, Martin NC, Patel KR, Callaghan JD, Stella NA, Shanks RMQ. Thermoregulation of Prodigiosin Biosynthesis by Serratia marcescens is Controlled at the Transcriptional Level and Requires HexS. Pol J Microbiol 2019; 68:43-50. [PMID: 31050252 PMCID: PMC6943984 DOI: 10.21307/pjm-2019-005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2018] [Indexed: 11/11/2022] Open
Abstract
Several biotypes of the Gram-negative bacterium Serratia marcescens produce the tri-pyrole pigment and secondary metabolite prodigiosin. The biological activities of this pigment have therapeutic potential. For over half a century it has been known that biosynthesis of prodi giosin is inhibited when bacteria are grown at elevated temperatures, yet the fundamental mechanism underlying this thermoregulation has not been characterized. In this study, chromosomal and plasmid-borne luxCDABE transcriptional reporters revealed reduced transcription of the prodigiosin biosynthetic operon at 37°C compared to 30°C indicating transcriptional control of pigment production. Moreover, induced expression of the prodigiosin biosynthetic operon at 37°C was able to produce pigmented colonies and cultures demonstrating that physiological conditions at 37°C allow prodigiosin production and indicating that post-transcriptional control is not a major contributor to the thermoregulation of prodigiosin pigmentation. Genetic experiments support the model that the HexS transcription factor is a key contributor to thermoregulation of pigmentation, whereas CRP plays a minor role, and a clear role for EepR and PigP was not observed. Together, these data indicate that thermoregulation of prodigiosin production at elevated temperatures is controlled largely, if not exclusively, at the transcriptional level.
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Affiliation(s)
- Eric G Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Kara M Lehner
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Natalie C Martin
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Kriya R Patel
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Jake D Callaghan
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Nicholas A Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
| | - Robert M Q Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh , Pittsburgh PA
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Dhaliwal DK, Jhanji V, Kowalski RP, Mammen A, Romanowski EG, Shanks RMQ. Endophthalmitis after intravitreal triamcinolone-moxifloxacin. J Cataract Refract Surg 2019; 45:705-706. [PMID: 31030793 DOI: 10.1016/j.jcrs.2019.01.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 01/30/2019] [Indexed: 11/17/2022]
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Romanowski EG, Yates KA, Shanks RMQ, Kowalski RP. Benzalkonium Chloride Demonstrates Concentration-Dependent Antiviral Activity Against Adenovirus In Vitro. J Ocul Pharmacol Ther 2019; 35:311-314. [PMID: 30969148 DOI: 10.1089/jop.2018.0145] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Purpose: Adenoviral conjunctivitis is the most common cause of conjunctivitis worldwide with no approved antiviral treatment. Benzalkonium chloride (BAK) is a common preservative in ophthalmic medications and is the active ingredient in some skin disinfectants and hand sanitizers. BAK is known to be effective in killing bacteria and enveloped viruses; however, its activity against ocular types of nonenveloped adenoviruses (Ads) is unknown. The goal was to determine whether BAK is an effective antiviral agent against common human ocular types of adenovirus in vitro. Methods: The direct inactivating activity of BAK was determined by incubating several human adenovirus types with BAK concentrations of 0.001%, 0.003%, 0.005%, 0.01%, 0.1%, and 0% for 1 h at 33°C. Resulting adenovirus titers were determined after treatment. Decreases in titers of ≥3 Log10 were considered virucidal, while decreases in titers of <1 Log10 were considered ineffective. Results: BAK 0.1% was virucidal for Ad3, Ad5, Ad7a, Ad19/64, and Ad37, while it reduced titers >1 Log10, but <3 Log10 for Ad4 and Ad8. Decreases in titers >1 Log10 were demonstrated for BAK 0.003%, 0.005%, and 0.01% for Ad5 only. Decreases in titers for the other adenovirus types for those concentrations were ≤0.53 Log10. 0.001% BAK produced minimal decreases in titers for all types. Conclusions: BAK, at 0.01% or less was not consistently effective as an antiviral against adenovirus, but higher concentrations, such as 0.1%, should be further investigated as a possible topical treatment for adenoviral ocular infections, providing ocular toxicity is not an issue.
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Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kathleen A Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Robert M Q Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Yates KA, Shanks RM, Kowalski RP, Romanowski EG. The In Vitro Evaluation of Povidone-Iodine Against Multiple Ocular Adenoviral Types. J Ocul Pharmacol Ther 2019; 35:132-136. [PMID: 30589605 PMCID: PMC6450451 DOI: 10.1089/jop.2018.0122] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 11/08/2018] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Povidone-iodine (P-I) is being touted as a topical antiviral treatment for eye infections caused by adenovirus (Ad). This study evaluated the in vitro antiviral activity of the several P-I concentrations previously used in clinical studies against multiple ocular Ad types commonly associated with eye infections. METHODS The antiviral activity of four concentrations of P-I was compared to vehicle for seven types of Ad after incubating the P-I with Ad at 33°C for various lengths of time. Following incubation and neutralization of the P-I with sodium thiosulfate, viral titers were determined for each Ad type and time point. RESULTS Virucidal (99.9%, ≥3-Log10) reductions in titers were produced for 5%, 2%, and 0.4% P-I at 1 min for types Ad5 and Ad7a. Similar reductions were produced at 5 min for types Ad3, Ad4, and Ad8. For type Ad19/64, virucidal reductions took 60 min for 5% P-I and 15 min for 2% and 0.4%. For type Ad37, 60 min (5%), 15 min (2%), and 5 min (0.4%) were required to produce virucidal reductions. There were no virucidal reductions in titers produced by 0.001% P-I. CONCLUSIONS P-I produced greater than 3-Log10 reductions of titers at 1-5 min for most of the ocular types tested (types Ad3, Ad4, Ad5, Ad7a, and Ad8). However, it took longer (15-60 min) for these reductions to be produced for types Ad19/64 and Ad37. The antiviral activity of P-I may be Ad type dependent.
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Affiliation(s)
- Kathleen A. Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Robert M.Q. Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Regis P. Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Eric G. Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Ismail AM, Cui T, Dommaraju K, Singh G, Dehghan S, Seto J, Shrivastava S, Fedorova NB, Gupta N, Stockwell TB, Halpin R, Madupu R, Heim A, Kajon AE, Romanowski EG, Kowalski RP, Malathi J, Therese KL, Madhavan HN, Zhang Q, Ferreyra LJ, Jones MS, Rajaiya J, Dyer DW, Chodosh J, Seto D. Author Correction: Genomic analysis of a large set of currently-and historically-important human adenovirus pathogens. Emerg Microbes Infect 2018; 7:208. [PMID: 30532034 PMCID: PMC6286714 DOI: 10.1038/s41426-018-0200-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ashrafali M Ismail
- Department of Ophthalmology, Howe Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114, USA
| | - Tiange Cui
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VA, 20110, USA
| | - Kalpana Dommaraju
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VA, 20110, USA
| | - Gurdeep Singh
- Department of Ophthalmology, Howe Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114, USA
| | - Shoaleh Dehghan
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VA, 20110, USA.,Chemistry Department, American University, Washington, DC, 20016, USA
| | - Jason Seto
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VA, 20110, USA
| | | | | | - Neha Gupta
- J. Craig Venter Institute, Rockville, MD, 20850, USA
| | | | | | - Ramana Madupu
- J. Craig Venter Institute, Rockville, MD, 20850, USA
| | - Albert Heim
- Institut für Virologie, Medizinische Hochschule Hannover, Hannover, 30625, Germany
| | - Adriana E Kajon
- Lovelace Respiratory Research Institute, Albuquerque, NM, 87108, USA
| | - Eric G Romanowski
- Charles T. Campbell Ophthalmic Microbiology Laboratory, Ear and Eye Institute, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Regis P Kowalski
- Charles T. Campbell Ophthalmic Microbiology Laboratory, Ear and Eye Institute, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Jambulingam Malathi
- L &, T Microbiology Research Center, Kamalnayan Bajaj Research Center, Sankara Nethralaya, No. 41 College Road, Chennai, Tamil Nadu, 600006, India
| | - Kuzhanthai L Therese
- L &, T Microbiology Research Center, Kamalnayan Bajaj Research Center, Sankara Nethralaya, No. 41 College Road, Chennai, Tamil Nadu, 600006, India
| | - Hajib Narahari Madhavan
- L &, T Microbiology Research Center, Kamalnayan Bajaj Research Center, Sankara Nethralaya, No. 41 College Road, Chennai, Tamil Nadu, 600006, India
| | - Qiwei Zhang
- Biosafety Level-3 Laboratory, School of Public Health, Southern Medical University, 510515, Guangzhou, China
| | - Leonardo J Ferreyra
- Institute of Virology "J. M. Vanella", Enfermera Gordillo Gómez s/n, Agencia 4, Ciudad Universitaria, CP 5016, Córdoba, Argentina
| | - Morris S Jones
- School of Public Health, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Jaya Rajaiya
- Department of Ophthalmology, Howe Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114, USA
| | - David W Dyer
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - James Chodosh
- Department of Ophthalmology, Howe Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114, USA.
| | - Donald Seto
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VA, 20110, USA.
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Lee J, Bilonick RA, Romanowski EG, Kowalski RP. Seasonal Variation in Human Adenovirus Conjunctivitis: A 30-Year Observational Study. Ophthalmic Epidemiol 2018; 25:451-456. [DOI: 10.1080/09286586.2018.1509096] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Jennifer Lee
- Department of Ophthalmology and Visual Sciences, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Richard A Bilonick
- Department of Ophthalmology and Visual Sciences, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- Department of Biostatistics, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, USA
| | - Eric G Romanowski
- Department of Ophthalmology and Visual Sciences, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Regis P Kowalski
- Department of Ophthalmology and Visual Sciences, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- The Charles T. Campbell Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Mammen A, Romanowski EG, Fedorchak MV, Dhaliwal DK, Shanks RM, Kowalski RP. Endophthalmitis Prophylaxis Using a Single Drop of Thermoresponsive Controlled-Release Microspheres Loaded with Moxifloxacin in a Rabbit Model. Transl Vis Sci Technol 2016; 5:12. [PMID: 27933222 PMCID: PMC5142715 DOI: 10.1167/tvst.5.6.12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 10/10/2016] [Indexed: 01/25/2023] Open
Abstract
Purpose Postsurgical endophthalmitis is a sight-threatening problem. We introduce a simple approach by using a single application of thermoresponsive controlled-release microspheres, loaded with moxifloxacin, to prevent bacterial endophthalmitis in a rabbit endophthalmitis prevention model. Methods We separated 24 rabbits into 3 treatment groups in which topical drop treatment was placed onto the conjunctival cul-de-sac: (1) a single drop of controlled-release microspheres containing moxifloxacin, (2) a single drop of controlled-release microspheres without moxifloxacin, and (3) multiple topical treatment with moxifloxacin alone every 15 minutes for 1 hour. All rabbits were challenged, 1 hour after microspheres drop placement and immediately after the fifth topical dose of moxifloxacin, with anterior chamber injections of Staphylococcus aureus. Rabbits in the topical moxifloxacin group also were treated after challenge and four additional times over the next 24 hours. After 24 hours, the rabbits were clinically evaluated for endophthalmitis and the animals were euthanized to culture for intraocular S. aureus. The treatment groups were compared statistically for bacterial endophthalmitis. Results No eyes had endophthalmitis, based on clinical presentation and/or positive culture, in the groups with controlled-release microspheres loaded with moxifloxacin (0/8, 0%) or multiple drops of topical moxifloxacin (0/8, 0%). In contrast, 8 of 8 eyes (100%; P = 0.0001), had endophthalmitis among eyes treated with controlled-release microspheres drops without moxifloxacin. Conclusion A single drop of controlled-release microspheres loaded with moxifloxacin was successful in preventing endophthalmitis. Further clinical studies will be required to confirm the full potential of controlled-release anti-infective loaded microspheres to prevent endophthalmitis. Translational Relevance This study presents a simple method of prophylaxis to prevent postsurgical endophthalmitis.
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Affiliation(s)
- Alex Mammen
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric G Romanowski
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Morgan V Fedorchak
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Deepinder K Dhaliwal
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - R M Shanks
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Regis P Kowalski
- University of Pittsburgh Medical Center (UPMC), The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Romanowski EG, Kowalski TA, O'Connor KE, Yates KA, Mah FS, Shanks RMQ, Kowalski RP. The In Vitro Evaluation of Tigecycline and the In Vivo Evaluation of RPX-978 (0.5% Tigecycline) as an Ocular Antibiotic. J Ocul Pharmacol Ther 2015; 32:119-26. [PMID: 26545167 DOI: 10.1089/jop.2015.0095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The goals of the current study were to determine the in vitro antibacterial activity of tigecycline against multiple clinically relevant ocular pathogens and to evaluate the in vivo ocular tolerability and efficacy of 0.5% tigecycline in a methicillin-resistant Staphylococcus aureus (MRSA) keratitis model. METHODS In vitro: Minimum inhibitory concentrations (MICs) were determined for 110 clinical conjunctivitis isolates, 26 keratitis isolates of Pseudomonas aeruginosa, and 10 endophthalmitis isolates each of MRSA, methicillin-susceptible S. aureus (MSSA), MR, and MS coagulase-negative Staphylococcus. TOLERABILITY Six uninfected rabbits were topically treated in both eyes with 0.5% tigecycline, vehicle, or saline every 15 min for 3 h. EFFICACY Thirty-two rabbits were intrastromally injected with 700 Colony Forming Units (CFU) of MRSA in both eyes and were separated into 4 groups (n = 8): tigecycline 0.5%; vancomycin 5%; saline; and no treatment (euthanized before treatment for baseline CFU). Four hours after MRSA challenge, topical treatment of 1 drop every 15 min for 5 h was initiated. One hour after treatment, the corneas were harvested for CFU. The data were analyzed nonparametrically. RESULTS In vitro: Tigecycline demonstrated lower MICs than the other tested antibiotics against gram-positive organisms, especially MRSA, while MICs against gram-negative pathogens, including fluoroquinolone-resistant P. aeruginosa, appeared to be in the treatable range with aggressive topical therapy. TOLERABILITY 0.5% tigecycline was graded as minimally irritating. EFFICACY 0.5% tigecycline and vancomycin produced similar reductions in CFU and were less than saline (P < 0.05). Tigecycline and vancomycin demonstrated 99.9% reductions compared with baseline CFU. CONCLUSIONS Tigecycline is a potential candidate for a topical ocular antibiotic.
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Affiliation(s)
- Eric G Romanowski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Tyler A Kowalski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Katherine E O'Connor
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Kathleen A Yates
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Francis S Mah
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Robert M Q Shanks
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Regis P Kowalski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
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Kowalski RP, Romanowski EG, Yates KA, Mah FS. An Independent Evaluation of a Novel Peptide Mimetic, Brilacidin (PMX30063), for Ocular Anti-infective. J Ocul Pharmacol Ther 2015; 32:23-7. [PMID: 26501484 DOI: 10.1089/jop.2015.0098] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE Brilacidin (BRI), a novel defensin mimetic, was evaluated as an ocular anti-infective. METHODS In vitro: Potency based on MIC90s was compared for 50 Staphylococcus aureus (SA), 50 Staphylococcus epidermidis (SE), and 25 each of Streptococcus pneumonia (SP), Streptococcus viridans (SV), Moraxella (MS), Haemophilus influenzae (HI), Pseudomonas aeruginosa (PA), and Serratia marcescens (SM). In vivo: Using established methods, ocular toxicity was graded with Draize testing. For efficacy testing, both corneas of 24 rabbits were infected with methicillin-resistant S. aureus (MRSA), whereas the corneal epithelium was removed in the left eye. After 4 h, 21 topical drops over 5 h were administered to 4 groups: BRI 0.5%, vancomycin (VAN) 5%, saline, and no treatment. The eyes were clinically graded and the corneas were harvested for colony counts. RESULTS In vitro: Both SA and SE had the lowest minimum inhibitory concentrations among the bacterial groups. The MIC90s to BRI for SP, SV, MS, HI, PA, and SM were 4, 32, 256, 32, 16, and 128-fold higher, respectively, than SA and SE. In vivo: Draize testing determined BRI 0.5% to be minimally irritating. For abraded corneas, BRI was not statistically different from VAN for reducing MRSA. BRI was bactericidal. For intact corneas, VAN reduced more CFU than BRI. BRI reduced CFU in abraded corneas more than intact corneas suggesting poor corneal penetration. CONCLUSIONS BRI has Gram-positive in vitro activity; topical BRI 0.5% was minimally irritating; and BRI 0.5% was equally efficacious as VAN in a MRSA keratitis model when the corneal epithelium was removed.
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Affiliation(s)
- Regis P Kowalski
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center (UPMC), University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Eric G Romanowski
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center (UPMC), University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Kathleen A Yates
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center (UPMC), University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Francis S Mah
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center (UPMC), University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
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Brothers KM, Nau AC, Romanowski EG, Shanks RMQ. Dexamethasone diffusion across contact lenses is inhibited by Staphylococcus epidermidis biofilms in vitro. Cornea 2015; 33:1083-7. [PMID: 25090165 DOI: 10.1097/ico.0000000000000196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE This study was designed to measure the impact of bacterial biofilms on diffusion of an ocular therapeutic through silicone hydrogel bandage lenses in vitro. METHODS An assay was designed to study the passage of a commonly used steroid, dexamethasone, through silicone hydrogel soft contact lenses. Diffused dexamethasone was measured using a spectrophotometer over a period of 18 hours and quantified using a standard curve. This assay was performed with control and Staphylococcus epidermidis biofilm-coated contact lenses comprised of lotrafilcon A and methafilcon. Biofilms were formed in brain heart infusion broth supplemented with D-glucose. RESULTS The presented data validate a simple in vitro model that can be used to measure the penetration of a topical therapeutic through silicone hydrogel soft contact lenses. Using this model, we measured a reduction in dexamethasone diffusion up to 88% through S. epidermidis biofilm-coated silicone hydrogel lenses compared with control lenses. CONCLUSIONS The results of this in vitro study demonstrate that bacterial biofilms impede dexamethasone diffusion through silicone hydrogel contact lenses and warrant future studies regarding the clinical benefit of using ocular therapeutics in the setting of bandage contact lens use for corneal epithelial defects.
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Affiliation(s)
- Kimberly M Brothers
- *Department of Ophthalmology (OVSRC), Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, University of Pittsburgh School of Medicine, Pittsburgh, PA; and †Department of Ophthalmology, Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Kowalski RP, Abdel Aziz S, Romanowski EG, Shanks RMQ, Nau AC, Raju LV. Development of a practical complete-kill assay to evaluate anti-Acanthamoeba drugs. JAMA Ophthalmol 2014; 131:1459-62. [PMID: 24077460 DOI: 10.1001/jamaophthalmol.2013.5062] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Acanthamoeba keratitis is a debilitating eye disease that requires effective topical drug therapy. Currently, there is no standard in vitro test to evaluate anti-Acanthamoeba drugs. OBJECTIVE To develop a practical in vitro complete-kill assay to assess anti-Acanthamoeba drugs. DESIGN AND SETTING Isolates of Acanthamoeba strains (n = 15) evaluated in a clinical laboratory. An in vitro laboratory assay was created to determine whether polyhexamethylene biguanide, 0.02%, chlorhexidine digluconate, 0.02%, hexamidine diisethioonate, 0.1%, and voriconazole, 1.0%, were effective in completely killing 15 different isolates of Acanthamoeba at time points of 24, 48, and 72 hours in comparison with a saline control. Each 0.5-mL volume of drug was inoculated with 0.1 mL of Acanthamoeba cysts (range, 1-3 × 10(6)/mL) (determined with a hemacytometer) and allowed to incubate at 30°C. At the time points listed, 0.05 mL from each treatment group was inoculated onto nonnutrient agar overlaid with Enterobacter aerogenes. The plates were microscopically examined for growth 1 and 2 weeks after inoculation. At 2 weeks, all plates were subcultured onto a fresh medium. At another 7 days, the growth in subculture at each time point was graded "1" for growth and "0" for no growth. MAIN OUTCOMES AND MEASURES The cumulative grades of 3 time points (range, 0-3) for each drug and isolate were nonparametrically compared to determine differences in growth between the drugs. The "kill" incidence rates over the 3 time points were also compared. RESULTS In vitro testing determined that antiacanthamoebal efficacy (determined by the median growth grade and the kill incidence rate) was more prominent for hexamidine diisethioonate (median growth grade, 0.0; kill incidence rate, 93% [14 of 15 isolates]) and polyhexamethylene biguanide (median growth grade, 0.0; kill incidence rate, 80% [12 of 15 isolates]) than for chlorhexidine digluconate (median growth grade, 1.0; kill incidence rate, 40% [6 of 15 isolates]), voriconazole (median growth grade, 2.0; kill incidence rate, 13% [2 of 15 isolates]), and saline (median growth grade, 3.0; kill incidence rate, 0% [0 of 15 isolates]). CONCLUSIONS AND RELEVANCE The complete-kill assay appears to provide separation in the effectiveness of different antiamoebic drug solutions. This assay may be helpful for guiding topical Acanthamoeba therapy and providing a practical method to evaluate and screen new anti-infectives in the treatment of Acanthamoeba keratitis.
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Affiliation(s)
- Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, the Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Shanks RMQ, Davra VR, Romanowski EG, Brothers KM, Stella NA, Godboley D, Kadouri DE. An Eye to a Kill: Using Predatory Bacteria to Control Gram-Negative Pathogens Associated with Ocular Infections. PLoS One 2013; 8:e66723. [PMID: 23824756 PMCID: PMC3688930 DOI: 10.1371/journal.pone.0066723] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/10/2013] [Indexed: 11/18/2022] Open
Abstract
Ocular infections are a leading cause of vision loss. It has been previously suggested that predatory prokaryotes might be used as live antibiotics to control infections. In this study, Pseudomonas aeruginosa and Serratia marcescens ocular isolates were exposed to the predatory bacteria Micavibrio aeruginosavorus and Bdellovibrio bacteriovorus. All tested S. marcescens isolates were susceptible to predation by B. bacteriovorus strains 109J and HD100. Seven of the 10 P. aeruginosa isolates were susceptible to predation by B. bacteriovorus 109J with 80% being attacked by M. aeruginosavorus. All of the 19 tested isolates were found to be sensitive to at least one predator. To further investigate the effect of the predators on eukaryotic cells, human corneal-limbal epithelial (HCLE) cells were exposed to high concentrations of the predators. Cytotoxicity assays demonstrated that predatory bacteria do not damage ocular surface cells in vitro whereas the P. aeruginosa used as a positive control was highly toxic. Furthermore, no increase in the production of the proinflammatory cytokines IL-8 and TNF-alpha was measured in HCLE cells after exposure to the predators. Finally, injection of high concentration of predatory bacteria into the hemocoel of Galleria mellonella, an established model system used to study microbial pathogenesis, did not result in any measurable negative effect to the host. Our results suggest that predatory bacteria could be considered in the near future as a safe topical bio-control agent to treat ocular infections.
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Affiliation(s)
- Robert M. Q. Shanks
- Department of Ophthalmology, Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, United States of America
| | - Viral R. Davra
- Department of Oral Biology, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, United States of America
| | - Eric G. Romanowski
- Department of Ophthalmology, Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, United States of America
| | - Kimberly M. Brothers
- Department of Ophthalmology, Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, United States of America
| | - Nicholas A. Stella
- Department of Ophthalmology, Campbell Laboratory of Ophthalmic Microbiology, University of Pittsburgh, Pittsburgh, United States of America
| | - Dipti Godboley
- Department of Oral Biology, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, United States of America
| | - Daniel E. Kadouri
- Department of Oral Biology, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, United States of America
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Romanowski EG, Yates KA, O'Connor KE, Mah FS, Shanks RMQ, Kowalski RP. Evaluation of polyhexamethylene biguanide (PHMB) as a disinfectant for adenovirus. JAMA Ophthalmol 2013; 131:495-8. [PMID: 23450376 DOI: 10.1001/jamaophthalmol.2013.2498] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Swimming pools can be a vector for transmission of adenovirus ocular infections. Polyhexamethylene biguanide (PHMB) is a disinfectant used in swimming pools and hot tubs. OBJECTIVE To determine whether PHMB is an effective disinfectant against ocular adenovirus serotypes at a concentration used to disinfect swimming pools and hot tubs. DESIGN In vitro laboratory study. INTERVENTIONS The direct disinfecting activity of PHMB was determined in triplicate assays by incubating 9 human adenovirus types (1, 2, 3, 4, 5, 7a, 8, 19, and 37) with PHMB concentrations of 50 and 0 ppm (micrograms per milliliter) for 24 hours at room temperature to simulate swimming pool temperatures or 40oC to simulate hot tub temperatures. MAIN OUTCOME MEASURES Plaque assays were performed to determine adenovirus titers after incubation. Titers were log10 converted and mean (SD) log10 reductions relative to controls were calculated. Virucidal (>99.9%) decreases in mean adenovirus titers after PHMB treatment were determined for each adenovirus type and temperature tested. RESULTS At room temperature, 50 ppm of PHMB produced mean reductions in titers less than 1 log10 for all adenovirus types tested. At 40°C, 50 ppm of PHMB produced mean reductions in titers less than 1 log10 for 2 adenovirus types and greater than 1 but less than 3 log10 for 7 of 9 adenovirus types. CONCLUSIONS AND RELEVANCE At a concentration of 50 ppm, PHMB was not virucidal against adenovirus at temperatures consistent with swimming pools or hot tubs. Recreational water maintained and sanitized with PHMB can serve as a vector for the transmission of ocular adenovirus infections.
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Kowalski RP, Romanowski EG, Shanks RM, Mah FS. Response to Carifi and Kopsachilis. J Ocul Pharmacol Ther 2013; 29:381. [DOI: 10.1089/jop.2012.0274.rs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Regis P. Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Eric G. Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Robert M.Q. Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Francis S. Mah
- The Charles T. Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh Medical Center, the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Kowalski RP, Romanowski EG, Shanks RMQ, Mah FS. The comparison of fluoroquinolones to nonfluoroquinolone antibacterial agents for the prevention of endophthalmitis in a rabbit model. J Ocul Pharmacol Ther 2012; 28:604-8. [PMID: 22925112 DOI: 10.1089/jop.2012.0073] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Topical antibacterial agents, used as an off-label indication, are frequently administered pre- and postoperatively to prevent endophthalmitis. We compared topical treatment with fluoroquinolone (FQ) anti-infectives to non-FQ antibacterial agents to prevent Staphylococcus aureus endophthalmitis. We hypothesize that FQ anti-infectives are more effective than non-FQ antibacterial agents for preventing endophthalmitis. METHODS Moxifloxacin 0.5%, ofloxacin 0.3%, gentamicin 0.3%, chloramphenicol 0.5%, polymyxin B/trimethoprim (10,000 units/mL/0.1%), povidone-iodine 5%, and saline were tested for topical treatment to prevent endophthalmitis. Topical treatment was applied every 15 min for 1 h (5 drops) to the left eye of 14 rabbits for each antibacterial agent and saline. After appropriate anesthesia, the anterior chambers were injected with 1×10(5) colony-forming units of a clinical endophthalmitis isolate of a S. aureus that was susceptible to all tested antibacterials. One drop was administered immediately and another 4 drops of topical treatment were applied over 24 h after injection. At 24 h postinjection, the eyes were graded for clinical signs of endophthalmitis (ocular discharge, conjunctivitis/scleral injection, limbal injection, hypopyon*, iritis*, anterior chamber cells*, anterior chamber flare*, corneal infiltration, and fibrin production*) using a severity scale (0-3). The indication of clinical endophthalmitis was a total score of >3.0 for the presentations marked with an asterisk. The data were analyzed using Fisher's Exact Randomization or Mann-Whitney nonparametric testing. RESULTS Topical ofloxacin (14/14, 100% without endophthalmitis) and moxifloxacin (13/14, 93%) prevented the clinical presentation of endophthalmitis significantly more frequently (P=0.03, Fisher's Exact Test (FE)) than topical gentamicin (7/14, 50%), povidone iodine (4/14, 29%), chloramphenicol (0/14, 0%), polymyxin B/trimethoprim (0/14, 0%), and saline (0/14, 0%). The median total clinical scores for the ofloxacin (0.5) and moxifloxacin (0.8) groups were significantly (P=0.008, Mann-Whitney Test (MW)) lower than gentamicin (5.7), chloramphenicol (17.5), polymyxin B/trimethoprim (21.2), povidone-iodine (15.5), and saline (18.7). CONCLUSIONS The FQs, ofloxacin and moxifloxacin, were more effective in preventing endophthalmitis than the non-FQ antibacterial agents in a rabbit S. aureus endophthalmitis model. The observed results are consistent with the hypothesis that FQs penetrate into the anterior chamber at more effective levels than many of the common non-FQ antibacterial agents.
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Affiliation(s)
- Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
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Rarey KA, Shanks RMQ, Romanowski EG, Mah FS, Kowalski RP. Staphylococcus aureus isolated from endophthalmitis are hospital-acquired based on Panton-Valentine leukocidin and antibiotic susceptibility testing. J Ocul Pharmacol Ther 2011; 28:12-6. [PMID: 22014156 DOI: 10.1089/jop.2011.0107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Staphylococcus aureus (SA) endophthalmitis is generally a postsurgical infection with an undefined source of entry. Hospital-acquired (HA) SA infections are associated with multi-antibiotic resistance and absence of the Panton-Valentine Leukocidin (PVL) toxin. Community-acquired (CA) SA infections are not associated with multi-antibiotic resistance and possess the PVL toxin. We hypothesize that CA infection is more common than HA for SA endophthalmitis. METHODS Twenty de-identified SA isolates, collected from the vitreous and/or aqueous of clinical endophthalmitis, were tested for the presence of PVL toxin and antibiotic susceptibility. PVL testing was performed using a kit to detect the Staphylococcal toxin by reversed passive latex agglutination (PVL-RPLA "Seiken," Denka Seiken Co., LTD). SA isolates were tested for antibiotic susceptibility using disk diffusion at the time of isolation. Multi-antibiotic resistance was defined as resistance to at least 3 classes of antibiotics. RESULTS Of the 20 isolates, 15 were multi-antibiotic resistant and PVL-negative consistent with HA, and 1 was not multi-antibiotic resistant and PVL-positive, consistent with CA. Two isolates tested positive for PVL with one demonstrating both methicillin and fluoroquinolone (FQ) resistance. Of the 18 PVL-negative SA isolates, 15 (83%) were multi-antibiotic resistant (12 methicillin-resistant SA, 14 FQ resistant). CONCLUSIONS Our results reject the hypothesis that SA isolated from endophthalmitis is consistent with CA sources due to the lack of the PVL toxin and multiple resistant patterns of the SA. PVL does not appear to be a key virulence factor for the development of SA endophthalmitis.
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Affiliation(s)
- Kristin A Rarey
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
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Wu EC, Kowalski RP, Romanowski EG, Mah FS, Gordon YJ, Shanks RMQ. AzaSite® inhibits Staphylococcus aureus and coagulase-negative Staphylococcus biofilm formation in vitro. J Ocul Pharmacol Ther 2010; 26:557-62. [PMID: 21029017 DOI: 10.1089/jop.2010.0097] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The aim of this study was to analyze the effect of azithromycin (AZM) 1% ophthalmic solution in DuraSite® (AzaSite®) on biofilm formation by Staphylococcus aureus and coagulase-negative staphylococci in vitro. METHODS Susceptible and resistant clinical strains (n = 8) of S. aureus and coagulase-negative staphylococci were challenged with serial dilutions of AzaSite® and its components: AZM, benzalkonium chloride (BAK), and the DuraSite drug delivery vehicle. After 20 h of incubation, bacterial growth was quantified using a spectrophotometer (A = 600 nm). Plates were stained with crystal violet and biofilm formation was quantified spectrophotometrically at A = 590 nm. RESULTS AzaSite® and AZM inhibited bacterial growth (P < 0.05) and biofilm formation (P < 0.05) in AZM-susceptible strains at all studied dilutions. AZM-resistant strains treated with AzaSite® exhibited a significant reduction in biofilm formation (P < 0.05) at subinhibitory concentrations (1.25%-5%). AZM had no effect on bacterial growth in resistant strains but conferred a small reduction in biofilm formation at concentrations from 1.25 to 10 mg/mL in most strains. DuraSite® inhibited biofilm formation at concentrations between 10% and 2.5% in all studied strains (P < 0.05), without affecting bacterial growth. BAK inhibited bacterial growth and biofilm formation in all strains between concentrations of 0.042 and 0.375 mg/mL (P < 0.05). CONCLUSIONS AzaSite®, AZM, or BAK prevented biofilm formation by inhibiting growth of AZM-susceptible strains. AzaSite®, AZM, and DuraSite® also reduced biofilm formation at subinhibitory concentrations for growth. Our data indicate that AZM has a moderate inhibitory effect on biofilm formation, whereas DuraSite® appears to play a greater role in the inhibition of staphylococcal biofilm formation by AzaSite®.
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Affiliation(s)
- Eric C Wu
- UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA
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Abstract
PURPOSE To determine whether topical levofloxacin 1.5% will successfully treat both levofloxacin-resistant and susceptible Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) in rabbit keratitis models. METHODS For levofloxacin-resistant and susceptible SA, respectively, 32 New Zealand White (NZW) rabbits were intrastromally injected with 1000 colony-forming units (CFU). After 4 hr, the corneas of eight rabbits were homogenized to determine onset CFU/ml. Twenty-four rabbits were divided into three treatments: levofloxacin, vancomycin (cefazolin for levofloxacin-susceptible SA) and saline. Twenty-one drops were administered over 5 hr. One hour post-treatment, the corneas were homogenized for CFU/ml. For levofloxacin-resistant and susceptible PA, respectively, 32 NZW rabbits were intrastromally injected with 1000 CFU. After 16 hr, the corneas of eight rabbits were homogenized for CFU/ml. Twenty-four rabbits were divided into three treatments: levofloxacin, tobramycin (ciprofloxacin for levofloxacin-susceptible PA) and saline. Nineteen drops were administered over 8 hr. One hour post-treatment, the corneas were homogenized for CFU/ml. The CFU/ml data were analysed for sterilization and non-parametrically for reduction. RESULTS Levofloxacin 1.5% significantly reduced more (p < 0.05) levofloxacin-resistant SA than vancomycin; was equivalent to cefazolin (p > 0.05) for levofloxacin-susceptible SA; was equivalent to tobramycin for levofloxacin-resistant PA; was equivalent to ciprofloxacin for levofloxacin-susceptible PA; and significantly reduced more SA and PA than saline and onset. Levofloxacin 1.5% sterilized the corneas in the levofloxacin-resistant and susceptible PA groups (32/32) and levofloxacin-susceptible SA group (16/16), but not the levofloxacin-resistant SA group (0/16). CONCLUSION Levofloxacin 1.5% was effective for reducing SA and PA in the rabbit keratitis models regardless of in vitro resistance.
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Affiliation(s)
- Regis P Kowalski
- Department of Ophthalmology/Microbiology, The Eye & Ear Institute of Ophthalmology/Microbiology, University of Pittsburgh, Pittsburgh, PA 15213, USA.
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Romanowski EG, Bartels SP, Vogel R, Wetherall NT, Hodges-Savola C, Kowalski RP, Yates KA, Kinchington PR, Gordon YJ. Feasibility of an antiviral clinical trial requiring cross-country shipment of conjunctival adenovirus cultures and recovery of infectious virus. Curr Eye Res 2009; 29:195-9. [PMID: 15512967 DOI: 10.1080/02713680490504830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE Accurate and timely laboratory diagnosis of adenovirus from conjunctival cultures is essential to ensure appropriate enrollment, and detection of residual infectious virus is essential to evaluate antiviral efficacy in any multicenter national clinical trial. As part of a feasibility study, we investigated those variables that might affect the successful recovery of infectious adenovirus from patient conjunctival cultures after cross-country shipment. MATERIALS AND METHODS Simulated adenovirus conjunctival cultures were prepared in viral transport media to evaluate the effect of four variables (adenovirus serotype, initial concentration, initial storage temperature [-20 degrees C, 0 degrees C, 20 degrees C], and preshipment storage times [1-5 days]) on the recovery of infectious adenovirus by a central laboratory in St. Paul, MN, following air shipment from Pittsburgh, PA. Upon arrival, the internal temperatures of the containers were recorded, and the samples were cultured on A549 cells using standard tube and/or shell vial culture. RESULTS Overall, adenovirus was recovered in 352/354 (99.4%) of the samples when the initial titer was greater than 1.0 PFU/ml. Adenovirus serotype, initial storage temperature, and preshipment storage times had no adverse effect on virus recovery. CONCLUSIONS Simulated conjunctival samples could successfully be shipped cross-country at ambient temperatures to a commercial laboratory for adenovirus isolation by culture. Having demonstrated feasibility, a clinical trial was subsequently carried out that confirmed the ease of shipment and recovery of infectious adenovirus from conjunctival cultures.
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Affiliation(s)
- Eric G Romanowski
- Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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Romanowski EG, Yates KA, Gordon YJ. The in vitro and in vivo evaluation of ddC as a topical antiviral for ocular adenovirus infections. Invest Ophthalmol Vis Sci 2009; 50:5295-9. [PMID: 19516011 DOI: 10.1167/iovs.08-3286] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate the antiviral activity of 2', 3'-dideoxycytidine (ddC) in vitro against a panel of ocular adenovirus serotypes and in vivo in the ocular Ad5/NZW rabbit replication model. METHODS In vitro, the 50% inhibitory concentrations (IC(50)) of ddC and cidofovir were determined using standard plaque-reduction assays. In vivo, 40 rabbits were topically inoculated in both eyes with Ad5 after corneal scarification. On day 1, the rabbits were equally divided into four topical treatment groups: 3% ddC; 2% ddC; 0.5% cidofovir; and saline. ddC and saline eyes were treated four times daily for 7 days, and cidofovir-treated eyes were treated twice daily for 7 days. Eyes were cultured for virus a multiple times over 2 weeks. RESULTS The in vitro IC(50) for ddC ranged from 0.18 to 1.85 microg/mL, whereas those for cidofovir ranged from 0.018 to 5.47 microg/mL. ddC was more potent than cidofovir for seven of nine serotypes. In vivo, 3% ddC, 2% ddC, and 0.5% cidofovir significantly reduced the number of Ad5-positive cultures per total (days 1-14), mean Ad5 ocular titer (days 1-5), and duration of shedding (among other outcome measures) compared with the saline control. The 3% and 2% ddC treatments were significantly more efficacious than the 0.5% cidofovir treatment in the parameters listed above. CONCLUSIONS ddC demonstrated potent antiadenovirus activity in vitro and in vivo. Systemic safety studies after topical ocular administration are needed to evaluate ddC as a topical antiviral treatment for adenoviral ocular infections in the target population.
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Affiliation(s)
- Eric G Romanowski
- Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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Gordon YJ, Romanowski EG, Shanks RMQ, Yates KA, Hinsley H, Pereira HA. CAP37-derived antimicrobial peptides have in vitro antiviral activity against adenovirus and herpes simplex virus type 1. Curr Eye Res 2009; 34:241-9. [PMID: 19274533 DOI: 10.1080/02713680802714066] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE The antiviral activity of an established antibacterial CAP37 domain and its extracellular mechanism of action were investigated. METHODS CAP37-derived peptides modified to assess the importance of disulfide bonds were evaluated in cytotoxicity and antiviral assays (direct time kill, dose dependency, and TOTO-1) for adenovirus (Ad) and herpes simplex virus type 1 (HSV-1). RESULTS Variable virus, adenovirus serotype-dependent, and dose-dependent inhibition were demonstrated without cytotoxicity. For peptide A (CAP37(20-44)), TOTO-1 dye uptake was demonstrated for Ad5 and HSV-1. CONCLUSIONS Unlike the antibacterial activity of this CAP37 domain, its antiviral activity is not fully dependent upon disulfide bond formation. Viral inhibition appears to result, in part, from disruption of the envelope and/or capsid.
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Affiliation(s)
- Y Jerold Gordon
- The Charles T. Campbell Lab Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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Siamak NM, Kowalski RP, Thompson PP, Romanowski EG, Shanks RMQ, Gordon YJ. RPS Adeno Detector. Ophthalmology 2009; 116:591-591.e1. [PMID: 19264216 DOI: 10.1016/j.ophtha.2008.10.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 10/23/2008] [Indexed: 11/15/2022] Open
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Romanowski EG, Mah FS, Kowalski RP, Yates KA, Gordon YJ. Benzalkonium chloride enhances the antibacterial efficacy of gatifloxacin in an experimental rabbit model of intrastromal keratitis. J Ocul Pharmacol Ther 2009; 24:380-4. [PMID: 18665809 DOI: 10.1089/jop.2008.0017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The aim of this study was to determine whether a preservative (0.005% benzalkonium chloride [BAK]) enhances the antibacterial efficacy of an antibiotic (0.3% gatifloxacin, [GAT]) in vivo. METHODS Rabbits were inoculated intrastromally with GAT-resistant, methicillin-resistant Staphylococcus aureus or Staphylococcus epidermidis and then divided into four treatment groups: 0.3% GAT + 0.005% BAK; 0.3% GAT without BAK; vehicle including 0.005% BAK; and saline control. At 4 h postinoculation, topical treatment was initiated in both eyes every 15 min for 5 h. One (1) h after therapy, corneal colony counts were determined. RESULTS For S. aureus, duplicate experiments demonstrated that GAT + BAK and GAT without BAK significantly reduced colony counts, compared with BAK or saline (P < 0.05). Further, GAT + BAK significantly reduced colony counts, compared with GAT without BAK. BAK alone was equivalent to the saline control. For S. epidermidis, duplicate experiments demonstrated that GAT + BAK and GAT without BAK significantly reduced colony counts, compared with BAK or saline (P < 0.05). There were no differences between GAT + BAK and GAT without BAK for S. epidermidis. CONCLUSIONS For the first time, we demonstrated that a preservative (0.005% BAK) significantly enhanced the antibacterial efficacy of an antibiotic (0.3% GAT) in an experimental rabbit model of intrastromal keratitis.
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Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
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Romanowski EG, Gordon YJ. Update on antiviral treatment of adenoviral ocular infections. Am J Ophthalmol 2008; 146:635-7. [PMID: 18984083 DOI: 10.1016/j.ajo.2008.07.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 07/15/2008] [Accepted: 07/15/2008] [Indexed: 12/01/2022]
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Kowalski RP, Romanowski EG, Mah FS, Yates KA, Gordon YJ. Topical 0.5% Moxifloxacin Prevents Endophthalmitis in an Intravitreal Injection Rabbit Model. J Ocul Pharmacol Ther 2008; 24:1-7. [DOI: 10.1089/jop.2007.0071] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Regis P. Kowalski
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Eric G. Romanowski
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Francis S. Mah
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Kathleen A. Yates
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Y. Jerold Gordon
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Nwanegbo EC, Romanowski EG, Gordon YJ, Gambotto A. Efficacy of topical immunoglobulins against experimental adenoviral ocular infection. Invest Ophthalmol Vis Sci 2007; 48:4171-6. [PMID: 17724203 PMCID: PMC2039928 DOI: 10.1167/iovs.07-0491] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Presently, there is no U.S. Federal Drug Administration (FDA)-approved antiviral therapy for the treatment of adenoviral (Ad) ocular infections. The goal of the present study was to determine the antiviral efficacy of human immunoglobulin (Ig), a preparation of highly purified and concentrated immunoglobulin (IgG) antibodies isolated from a large pool of human plasma donors, in vitro and on acute Ad replication in the Ad5 New Zealand White (NZW) rabbit ocular model. METHODS The antiviral activity of human Ig against multiple wild-type and human ocular isolates of adenovirus serotypes was investigated in vitro by using neutralizing assays in different human epithelial cell lines. In vivo bilateral topical ocular toxicity and antiviral efficacy were evaluated with established Ad5/NZW rabbit ocular models. In vivo Ig antiviral results were compared with those obtained with topical 0.5% cidofovir and saline. RESULTS In three different epithelial cell lines, <or=6.25 mg/mL of the Ig neutralized several wild-type adenoviral serotypes that cause ocular infections. A dose of <or=10 mg/mL neutralized 88% of ocular isolates of the adenovirus serotypes. After treatment of infected animals, adenovirus-positive cultures per total cultures (days 1-14; P = 0.021), the duration of Ad5 shedding, (P = 0.008), and the mean combined ocular viral titer during the early (days 1-5; P = 0.0001) and the late (days 7-14; P = 0.013) phases of infection were significantly lower in Ig-treated animals than in saline-treated animals and were similar to those in cidofovir-treated animals. CONCLUSIONS Ig demonstrated antiviral properties against multiple adenoviral serotypes in vitro and in the Ad5/NZW rabbit ocular model. Further studies are needed to advance topical immunoglobulin for treatment and prophylaxis of ocular infections.
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MESH Headings
- Adenovirus Infections, Human/drug therapy
- Adenovirus Infections, Human/virology
- Adenoviruses, Human/isolation & purification
- Adenoviruses, Human/physiology
- Administration, Topical
- Animals
- Antiviral Agents/administration & dosage
- Antiviral Agents/toxicity
- Cell Culture Techniques
- Cidofovir
- Conjunctiva/virology
- Cornea/virology
- Cytosine/administration & dosage
- Cytosine/analogs & derivatives
- Cytosine/toxicity
- Disease Models, Animal
- Epithelial Cells/virology
- Eye Infections, Viral/drug therapy
- Eye Infections, Viral/virology
- Flow Cytometry
- Immunoglobulins, Intravenous/therapeutic use
- Immunoglobulins, Intravenous/toxicity
- Immunologic Factors/therapeutic use
- Immunologic Factors/toxicity
- Keratoconjunctivitis/drug therapy
- Keratoconjunctivitis/virology
- Organophosphonates/administration & dosage
- Organophosphonates/toxicity
- Rabbits
- Treatment Outcome
- Virus Cultivation
- Virus Replication/drug effects
- Virus Shedding
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Affiliation(s)
- Edward C. Nwanegbo
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Eric G. Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center (OVSRC), Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Y. Jerold Gordon
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center (OVSRC), Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Andrea Gambotto
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Mah FS, Romanowski EG, Kowalski RP, Yates KA, Gordon YJ. Zymar (Gatifloxacin 0.3%) shows excellent Gram-negative activity against Serratia marcescens and Pseudomonas aeruginosa in a New Zealand White rabbit keratitis model. Cornea 2007; 26:585-8. [PMID: 17525656 DOI: 10.1097/ico.0b013e318033a6f2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Whereas gatifloxacin, a newer fluoroquinolone, was engineered to increase its Gram-positive potency, we assessed whether it still retained significant Gram-negative activity in vivo. Specifically, we compared the efficacy of Zymar (gatifloxacin 0.3%), Ciloxan (ciprofloxacin 0.3%), and fortified tobramycin (14 mg/mL) in the treatment of experimental Gram-negative bacterial infections of Serratia marcescens (SM) and Pseudomonas aeruginosa (PA) in the New Zealand White (NZW) rabbit keratitis model. METHODS A total of 30 NZW rabbits each were intrastromally inoculated in both eyes with approximately 1000 CFU of SM and PA. By E-test, the minimum inhibitory concentrations (MICs; microg/mL) for SM were gatifloxacin (0.125), ciprofloxacin (0.047), and tobramycin (1.5), and for PA were gatifloxacin (0.125), ciprofloxacin (0.19), and tobramycin (0.5). After 16 hours, the rabbits were divided into 4 treatment groups: (1) Zymar, (2) Ciloxan, (3) fortified tobramycin, and (4) saline control. One drop was instilled in both eyes every 15 minutes for 5 doses and then every 30 minutes for 14 doses. One hour after the final treatment, the animals were euthanized, and bacterial colony counts from the corneas were determined. RESULTS For SM, Zymar and Ciloxan significantly reduced (P < 0.001, ANOVA) the colony counts compared with tobramycin and saline control. Zymar was more effective than Ciloxan (P < 0.001, ANOVA). For PA, all antibiotics reduced equivalently the colony counts compared with the saline control (P = 0.005, ANOVA). CONCLUSIONS The enhanced Gram-positive activity of gatifloxacin is not associated with any decreased Gram-negative activity in vivo. Zymar may prove useful for SM and PA keratitis.
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Affiliation(s)
- Francis S Mah
- Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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