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Rudraprasad D, Gandhi J, Naik P, N Naik M, Naidu C, Kumar Mishra D, Joseph J. A Novel and Low-cost Approach for Intravitreal Injection in an Experimental Model of Endophthalmitis. J Ophthalmic Vis Res 2023; 18:272-282. [PMID: 37600911 PMCID: PMC10432928 DOI: 10.18502/jovr.v18i3.13775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 01/01/2023] [Indexed: 08/22/2023] Open
Abstract
Purpose Animal models are necessary in understanding the pathogenesis of endophthalmitis and are also necessary to assist the development of new therapeutics for this sight-threatening ocular inflammation. Hamilton syringes are usually preferred to inject pathogens when performing experiments on test subjects, however, this method has technical and financial disadvantages. In this study, we report the findings and assess the related benefits of applying a novel low-cost intravitreal injection technique to initiate endophthalmitis in a mouse model while using the Eppendorf tip and a 26G needle. Methods The 18-hr culture of clinical isolates of bacteria (Staphylococcus aureus and Pseudomonas aeruginosa) and fungus (Aspergillus flavus and Candida albicans) were resuspended to a final concentration of 10,000 colony forming units (CFU)/1 µL which were separately injected intravitreally into C57BL/6 mice (6-8 weeks) using a 0.1-2.5µL pipette attached to the modified Eppendorf tip with a 26G needle. The contralateral eye served as vehicle/uninjected control. Disease progression was determined by assessing the corneal haze, opacity, bacterial burden, and retinal histology of the eyes used in the model. Following euthanization, bacteria-infected mice were enucleated after 24 hr of the initial injection, and fungus-infected mice after 72 hr. Results Of the 50 mice injected, the modified technique was successful in 48 mice. Two mice were excluded due to cataract formed by accidental injury to the lens. The experimental endophthalmitis mice model successfully mimicked the natural clinical course. Clinical assessment and histopathology confirmed the influx of inflammatory cells into the posterior segment of the eye along with dissolution of retinal architecture. Conclusion Our novel method of injection using a modified Eppendorf tip and 26G needle yielded a cost-effective mouse model of clinical endophthalmitis, resulting in reproducible infection for understanding various aspects of its pathobiology.
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Affiliation(s)
- Dhanwini Rudraprasad
- Jhaveri Microbiology Centre, Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
- Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Jaishree Gandhi
- Jhaveri Microbiology Centre, Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
- Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Poonam Naik
- Jhaveri Microbiology Centre, Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
- Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Milind N Naik
- Ophthalmic Plastic Surgery & Facial Aesthetics, LV Prasad Eye Institute, Hyderabad, India
| | - Chenchu Naidu
- Ophthalmic pathology Laboratory, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Dilip Kumar Mishra
- Ophthalmic pathology Laboratory, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Joveeta Joseph
- Jhaveri Microbiology Centre, Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
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Rottmann BG, Singh PK, Singh S, Revankar SG, Chandrasekar PH, Kumar A. Evaluation of Susceptibility and Innate Immune Response in C57BL/6 and BALB/c Mice During Candida albicans Endophthalmitis. Invest Ophthalmol Vis Sci 2020; 61:31. [PMID: 32940660 PMCID: PMC7500134 DOI: 10.1167/iovs.61.11.31] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 08/31/2020] [Indexed: 12/12/2022] Open
Abstract
Purpose Candida remains the leading cause of fungal endophthalmitis. However, the pathobiology and innate immune responses in this disease are not well characterized. Here, we developed two murine models of candida endophthalmitis and evaluated their disease susceptibility and differential immune response. Methods Endophthalmitis was induced in C57BL/6 (B6) and BALB/c mice by intravitreal injection of Candida albicans (CA). Disease progression was monitored by slit-lamp examination and clinical scoring, followed by retinal function assessment using electroretinography (ERG). Enucleated eyes were used to estimate fungal burden and retinal tissue damage by hematoxylin and eosin and TUNEL staining. The level of inflammatory mediators were determined by quantitative Polymerase Chain Reaction (qPCR) and enzyme-linked immunosorbent assay, whereas neutrophil infiltration was assessed by flow cytometry and immunostaining. Results Intravitreal injection of CA at 6500 colony-forming units resulted in sustained (non-resolving) ocular inflammation in both B6 and BALB/c mice as evidenced by increased levels of inflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6) and chemokine (CXCL2/MIP-2). In both mouse strains, fungal burden peaked at 24 to 48 hours post-infection (hpi) and decreased by 72 to 96 hpi. CA-infected eyes exhibited increased polymorphonuclear neutrophils (PMN) infiltration and retinal tissue damage. Overall retinal function declined rapidly, with a significant reduction in ERG response at 12 hpi and near-total loss by 24 hpi. Differential analyses revealed increased pathology in BALB/c versus B6 mice. Conclusions C. albicans was able to cause endophthalmitis in mice. Although BALB/c mice were found to be more susceptible to CA endophthalmitis, both BALB/c and B6 models could be used to study fungal endophthalmitis and test therapeutic modalities.
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Affiliation(s)
- Bruce G. Rottmann
- Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Pawan Kumar Singh
- Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Sneha Singh
- Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Sanjay G. Revankar
- Division of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Pranatharthi H. Chandrasekar
- Division of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Ashok Kumar
- Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, United States
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Dosmar E, Liu W, Patel G, Rogozinski A, Mieler WF, Kang-Mieler JJ. Controlled Release of Vancomycin From a Thermoresponsive Hydrogel System for the Prophylactic Treatment of Postoperative Acute Endophthalmitis. Transl Vis Sci Technol 2019; 8:53. [PMID: 31293808 PMCID: PMC6601710 DOI: 10.1167/tvst.8.3.53] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 04/22/2019] [Indexed: 12/26/2022] Open
Abstract
Purpose To investigate the efficacy of a poly(ethylene glycol) diacrylate and poly(N-isopropylacrylamide) based thermo-responsive hydrogel drug delivery system (DDS) to deliver prophylactic vancomycin (VAN) following ocular surgery. Methods VAN was encapsulated in a hydrogel DDS and characterized in terms of initial burst, release kinetics, bioactivity, and cytotoxicity. Long-Evans rats received an intravitreal injection of Staphylococcus aureus to produce acute endophthalmitis in four experimental groups. One of four treatments were then applied: (1) bolus subconjunctival injection of VAN, (2) blank DDS, (3) saline treatment, and (4) subconjunctival injection of VAN DDS. Animals were scored for infection (0–3) at 12, 24, 48, and 72 hours, and eyes were harvested at 24 and 48 hours for histology. Results Following a 36% initial burst, VAN release from the DDS continued at a steady rate for 2 weeks plateauing at 84% after 504 hours. Bioactivity was maintained for all release samples and cytotoxicity analysis for the DDS revealed cell viability >90%. Not until after 12 hours did any of the groups show evidence of infection; however, at 24 hours, animals that received the VAN DDS had significantly lower infection scores (0 ± 0) than those that received a bolus VAN injection, blank DDS, or saline (1.5 ±1.5, 2.3 ± 0.87, and 2.9 ± 0.25; respectively). At 48 and 72 hours, the VAN DDS and bolus VAN treatment groups performed comparably and showed significantly better infection scores than the control groups. Conclusions This DDS appears to have promise as a vehicle for short term, prophylactic antibiotic delivery. Translational Relevance This DDS may prevent the development of postoperative endophthalmitis.
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Affiliation(s)
- Emily Dosmar
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA
| | - Wenqiang Liu
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA
| | - Geeya Patel
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA
| | - Alison Rogozinski
- Department of Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| | - William F Mieler
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Jennifer J Kang-Mieler
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA
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O'Callaghan RJ. The Pathogenesis of Staphylococcus aureus Eye Infections. Pathogens 2018; 7:pathogens7010009. [PMID: 29320451 PMCID: PMC5874735 DOI: 10.3390/pathogens7010009] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 01/02/2018] [Accepted: 01/04/2018] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus is a major pathogen of the eye able to infect the tear duct, eyelid, conjunctiva, cornea, anterior and posterior chambers, and the vitreous chamber. Of these infections, those involving the cornea (keratitis) or the inner chambers of the eye (endophthalmitis) are the most threatening because of their potential to cause a loss in visual acuity or even blindness. Each of these ocular sites is protected by the constitutive expression of a variety of antimicrobial factors and these defenses are augmented by a protective host response to the organism. Such infections often involve a predisposing factor that weakens the defenses, such as the use of contact lenses prior to the development of bacterial keratitis or, for endophthalmitis, the trauma caused by cataract surgery or intravitreal injection. The structural carbohydrates of the bacterial surface induce an inflammatory response able to reduce the bacterial load, but contribute to the tissue damage. A variety of bacterial secreted proteins including alpha-toxin, beta-toxin, gamma-toxin, Panton-Valentine leukocidin and other two-component leukocidins mediate tissue damage and contribute to the induction of the inflammatory response. Quantitative animal models of keratitis and endophthalmitis have provided insights into the S. aureus virulence and host factors active in limiting such infections.
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Affiliation(s)
- Richard J O'Callaghan
- Department of Microbiology and Immunology, University of Mississippi Medical Center, 2500 N. State St., Jackson, MS 39216, USA.
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Yan Q, Ahn SH, Medie FM, Sharma-Kuinkel BK, Park LP, Scott WK, Deshmukh H, Tsalik EL, Cyr DD, Woods CW, Yu CHA, Adams C, Qi R, Hansen B, Fowler VG. Candidate genes on murine chromosome 8 are associated with susceptibility to Staphylococcus aureus infection in mice and are involved with Staphylococcus aureus septicemia in humans. PLoS One 2017; 12:e0179033. [PMID: 28594911 PMCID: PMC5464679 DOI: 10.1371/journal.pone.0179033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 05/23/2017] [Indexed: 02/06/2023] Open
Abstract
We previously showed that chromosome 8 of A/J mice was associated with susceptibility to S. aureus infection. However, the specific genes responsible for this susceptibility are unknown. Chromosome substitution strain 8 (CSS8) mice, which have chromosome 8 from A/J but an otherwise C57BL/6J genome, were used to identify the genetic determinants of susceptibility to S. aureus on chromosome 8. Quantitative trait loci (QTL) mapping of S. aureus-infected N2 backcross mice (F1 [C8A] × C57BL/6J) identified a locus 83180780–88103009 (GRCm38/mm10) on A/J chromosome 8 that was linked to S. aureus susceptibility. All genes on the QTL (n~ 102) were further analyzed by three different strategies: 1) different expression in susceptible (A/J) and resistant (C57BL/6J) mice only in response to S. aureus, 2) consistently different expression in both uninfected and infected states between the two strains, and 3) damaging non-synonymous SNPs in either strain. Eleven candidate genes from the QTL region were significantly differently expressed in patients with S. aureus infection vs healthy human subjects. Four of these 11 genes also exhibited significantly different expression in S. aureus-challenged human neutrophils: Ier2, Crif1, Cd97 and Lyl1. CD97 ligand binding was evaluated within peritoneal neutrophils from A/J and C57BL/6J. CD97 from A/J had stronger CD55 but weaker integrin α5β1 ligand binding as compared with C57BL/6J. Because CD55/CD97 binding regulates immune cell activation and cytokine production, and integrin α5β1 is a membrane receptor for fibronectin, which is also bound by S. aureus, strain-specific differences could contribute to susceptibility to S. aureus. Down-regulation of Crif1 with siRNA was associated with increased host cell apoptosis among both naïve and S. aureus-infected bone marrow-derived macrophages. Specific genes in A/J chromosome 8, including Cd97 and Crif1, may play important roles in host defense against S. aureus.
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Affiliation(s)
- Qin Yan
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Sun Hee Ahn
- Department of Biochemistry School of Dentistry, Chonnam National University, Bukgu, Gwangju, Korea
| | - Felix Mba Medie
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Batu K. Sharma-Kuinkel
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Lawrence P. Park
- Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
| | - William K. Scott
- Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miami, Florida, United States of America
| | - Hitesh Deshmukh
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Ephraim L. Tsalik
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Emergency Medicine Service, Durham Veteran’s Affairs Medical Center, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
| | - Derek D. Cyr
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
| | - Christopher W. Woods
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
- Section on Infectious Diseases, Durham Veteran’s Affairs Medical Center, Durham, North Carolina, United States of America
| | - Chen-Hsin Albert Yu
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Carlton Adams
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Robert Qi
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Brenda Hansen
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Vance G. Fowler
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
- * E-mail:
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Astley RA, Coburn PS, Parkunan SM, Callegan MC. Modeling intraocular bacterial infections. Prog Retin Eye Res 2016; 54:30-48. [PMID: 27154427 PMCID: PMC4992594 DOI: 10.1016/j.preteyeres.2016.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/15/2016] [Accepted: 04/24/2016] [Indexed: 12/31/2022]
Abstract
Bacterial endophthalmitis is an infection and inflammation of the posterior segment of the eye which can result in significant loss of visual acuity. Even with prompt antibiotic, anti-inflammatory and surgical intervention, vision and even the eye itself may be lost. For the past century, experimental animal models have been used to examine various aspects of the pathogenesis and pathophysiology of bacterial endophthalmitis, to further the development of anti-inflammatory treatment strategies, and to evaluate the pharmacokinetics and efficacies of antibiotics. Experimental models allow independent control of many parameters of infection and facilitate systematic examination of infection outcomes. While no single animal model perfectly reproduces the human pathology of bacterial endophthalmitis, investigators have successfully used these models to understand the infectious process and the host response, and have provided new information regarding therapeutic options for the treatment of bacterial endophthalmitis. This review highlights experimental animal models of endophthalmitis and correlates this information with the clinical setting. The goal is to identify knowledge gaps that may be addressed in future experimental and clinical studies focused on improvements in the therapeutic preservation of vision during and after this disease.
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Affiliation(s)
- Roger A Astley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Phillip S Coburn
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Salai Madhumathi Parkunan
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Michelle C Callegan
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Dean McGee Eye Institute, Oklahoma City, OK, USA.
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7
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Singh PK, Kumar A. Mitochondria mediates caspase-dependent and independent retinal cell death in Staphylococcus aureus endophthalmitis. Cell Death Discov 2016; 2:16034. [PMID: 27551524 PMCID: PMC4979429 DOI: 10.1038/cddiscovery.2016.34] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 04/25/2016] [Accepted: 04/28/2016] [Indexed: 12/18/2022] Open
Abstract
Bacterial endophthalmitis, a vision-threatening complication of ocular surgery or trauma, is characterized by increased intraocular inflammation and retinal tissue damage. Although significant vision loss in endophthalmitis has been linked to retinal cell death, the underlying mechanisms of cell death remain elusive. In this study, using a mouse model of Staphylococcus aureus endophthalmitis and cultured human retinal Müller glia (MIO-M1 cell line), we demonstrate that S. aureus caused significant apoptotic cell death in the mouse retina and Müller glia, as evidenced by increased number of terminal dUTP nick end labeling and Annexin V and propidium iodide-positive cells. Immunohistochemistry and western blot studies revealed the reduction in mitochondrial membrane potential (JC-1 staining), release of cytochrome c into the cytosol, translocation of Bax to the mitochondria and the activation of caspase-9 and -3 in S. aureus-infected retina/retinal cells. In addition, the activation of PARP-1 and the release of apoptosis inducing factor from mitochondria was also observed in S. aureus-infected retinal cells. Inhibition studies using pan-caspase (Q-VD-OPH) and PARP-1 (DPQ) inhibitors showed significant reduction in S. aureus-induced retinal cell death both in vivo and in vitro. Together, our findings demonstrate that in bacterial endophthalmitis, retinal cells undergo apoptosis in the both caspase-dependent and independent manners, and mitochondria have a central role in this process. Hence, targeting the identified signaling pathways may provide the rationale to design therapeutic interventions to prevent bystander retinal tissue damage in bacterial endophthalmitis.
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Affiliation(s)
- P K Singh
- Kresge Eye Institute/Department of Ophthalmology, Wayne State University, Detroit, MI, USA
- Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI, USA
| | - A Kumar
- Kresge Eye Institute/Department of Ophthalmology, Wayne State University, Detroit, MI, USA
- Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI, USA
- Department of Immunology and Microbiology, Wayne State University, Detroit, MI, USA
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8
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Rajamani D, Singh PK, Rottmann BG, Singh N, Bhasin MK, Kumar A. Temporal retinal transcriptome and systems biology analysis identifies key pathways and hub genes in Staphylococcus aureus endophthalmitis. Sci Rep 2016; 6:21502. [PMID: 26865111 PMCID: PMC4749995 DOI: 10.1038/srep21502] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 01/08/2016] [Indexed: 12/11/2022] Open
Abstract
Bacterial endophthalmitis remains a devastating inflammatory condition associated with permanent vision loss. Hence, assessing the host response in this disease may provide new targets for intervention. Using a mouse model of Staphylococcus aureus (SA) endophthalmitis and performing retinal transcriptome analysis, we discovered progressive changes in the expression of 1,234 genes. Gene ontology (GO) and pathway analyses revealed the major pathways impacted in endophthalmitis includes: metabolism, inflammatory/immune, antimicrobial, cell trafficking, and lipid biosynthesis. Among the immune/inflammation pathways, JAK/Stat and IL-17A signaling were the most significantly affected. Interactive network-based analyses identified 13 focus hub genes (IL-6, IL-1β, CXCL2, STAT3, NUPR1, Jun, CSF1, CYR61, CEBPB, IGF-1, EGFR1, SPP1, and TGM2) within these important pathways. The expression of hub genes confirmed by qRT-PCR, ELISA (IL-6, IL-1β, and CXCL2), and Western blot or immunostaining (CEBP, STAT3, NUPR1, and IGF1) showed strong correlation with transcriptome data. Since TLR2 plays an important role in SA endophthalmitis, counter regulation analysis of TLR2 ligand pretreated retina or the use of retinas from TLR2 knockout mice showed the down-regulation of inflammatory regulatory genes. Collectively, our study provides, for the first time, a comprehensive analysis of the transcriptomic response and identifies key pathways regulating retinal innate responses in staphylococcal endophthalmitis.
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Affiliation(s)
- Deepa Rajamani
- BIDMC Genomics, Proteomics, Bioinformatics and Systems Biology Center, Beth Israel Deaconess Medical Center, Boston, MA
| | - Pawan Kumar Singh
- Kresge Eye Institute, Wayne State University, Detroit, MI.,Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI
| | - Bruce G Rottmann
- Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI
| | - Natasha Singh
- BIDMC Genomics, Proteomics, Bioinformatics and Systems Biology Center, Beth Israel Deaconess Medical Center, Boston, MA
| | - Manoj K Bhasin
- BIDMC Genomics, Proteomics, Bioinformatics and Systems Biology Center, Beth Israel Deaconess Medical Center, Boston, MA.,Department of Medicine, Division of Interdisciplinary Medicine and Biotechnology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Ashok Kumar
- Kresge Eye Institute, Wayne State University, Detroit, MI.,Department of Anatomy and Cell Biology, Wayne State University, Detroit, MI.,Department of Immunology and Microbiology, Wayne State University, Detroit, MI
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Rogge M, Yin XT, Godfrey L, Lakireddy P, Potter CA, Del Rosso CR, Stuart PM. Therapeutic Use of Soluble Fas Ligand Ameliorates Acute and Recurrent Herpetic Stromal Keratitis in Mice. Invest Ophthalmol Vis Sci 2016; 56:6377-86. [PMID: 26444718 DOI: 10.1167/iovs.15-16588] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE The present study was designed to test the therapeutic value of soluble FasL (sFasL) in an acute model of herpetic stromal keratitis (HSK) and, more importantly, a recurrent model of HSK using BALB/c, BALB-lpr, and National Institutes of Health (NIH) mice. METHODS Mice were infected either acutely with the KOS strain of herpes simplex virus 1 (HSV-1) or latently with the McKrae strain of HSV-1. Acutely infected mice as well as ultraviolet-B (UV-B) reactivated mice (recurrent infection) were treated with sFasL, or soluble TNF-related apoptosis inducing ligand (sTRAIL), or BSA daily or 3 times/wk by using either a combination of subconjunctival injection and topical ointment, or with topical ointment alone. These mice then were evaluated for corneal opacity and neovascularization for 6 weeks. RESULTS Following acute and recurrent HSV-1 infection, wild-type BALB/c mice treated with sFasL displayed significantly reduced incidence of corneal opacity and neovascularization compared to the control animals. However, BALB-lpr mice, which are deficient in Fas+ inflammatory cells, displayed no such differences in ocular disease, as expected. Latently infected NIH mice treated with sFasL displayed similar results. Flow cytometric analysis revealed that the corneal inflammatory infiltrate in those treated with sFasL was significantly less than in sTRAIL- or BSA-treated mice. Furthermore, corneas from sFasL-treated mice displayed relatively more cells undergoing apoptosis. CONCLUSIONS This study provides evidence that sFasL treatment has potential therapeutic benefit in reducing inflammatory infiltrate and neovascularization in primary and recurrent forms of HSK, and that it does so by augmenting the restriction of Fas+ inflammatory cells mediated by membrane FasL.
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10
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Role of Staphylococcus aureus Virulence Factors in Inducing Inflammation and Vascular Permeability in a Mouse Model of Bacterial Endophthalmitis. PLoS One 2015; 10:e0128423. [PMID: 26053426 PMCID: PMC4459968 DOI: 10.1371/journal.pone.0128423] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 04/28/2015] [Indexed: 01/21/2023] Open
Abstract
Staphylococcus (S.) aureus is a common causative agent of bacterial endophthalmitis, a vision threatening complication of eye surgeries. The relative contribution of S. aureus virulence factors in the pathogenesis of endophthalmitis remains unclear. Here, we comprehensively analyzed the development of intraocular inflammation, vascular permeability, and the loss of retinal function in C57BL/6 mouse eyes, challenged with live S. aureus, heat-killed S. aureus (HKSA), peptidoglycan (PGN), lipoteichoic acid (LTA), staphylococcal protein A (SPA), α-toxin, and Toxic-shock syndrome toxin 1 (TSST1). Our data showed a dose-dependent (range 0.01 μg/eye to 1.0 μg/eye) increase in the levels of inflammatory mediators by all virulence factors. The cell wall components, particularly PGN and LTA, seem to induce higher levels of TNF-α, IL-6, KC, and MIP2, whereas the toxins induced IL-1β. Similarly, among the virulence factors, PGN induced higher PMN infiltration. The vascular permeability assay revealed significant leakage in eyes challenged with live SA (12-fold) and HKSA (7.3-fold), in comparison to other virulence factors (~2-fold) and controls. These changes coincided with retinal tissue damage, as evidenced by histological analysis. The electroretinogram (ERG) analysis revealed a significant decline in retinal function in eyes inoculated with live SA, followed by HKSA, SPA, and α-toxin. Together, these findings demonstrate the differential innate responses of the retina to S. aureus virulence factors, which contribute to intraocular inflammation and retinal function loss in endophthalmitis.
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11
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Talreja D, Singh PK, Kumar A. In Vivo Role of TLR2 and MyD88 Signaling in Eliciting Innate Immune Responses in Staphylococcal Endophthalmitis. Invest Ophthalmol Vis Sci 2015; 56:1719-32. [PMID: 25678692 DOI: 10.1167/iovs.14-16087] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PURPOSE The purpose of this study was to investigate the protective mechanisms evoked by TLR2 and MyD88 signaling in bacterial endophthalmitis in vivo. METHODS Endophthalmitis was induced in wild-type (WT), TLR2(-/-), MyD88(-/-), and Cnlp(-/-) mice by intravitreal injections of a laboratory strain (RN6390) and two endophthalmitis isolates of Staphylococcus aureus. Disease progression was monitored by assessing corneal and vitreous haze, bacterial burden, and retinal tissue damage. Levels of inflammatory cytokines/chemokines were determined using quantitative RT-PCR (qRT-PCR) and ELISA. Flow cytometry was used to assess neutrophil infiltration. Cathelicidin-related antimicrobial peptide (CRAMP) expression was determined by immunostaining and dot blot. RESULTS Eyes infected with either laboratory or clinical isolates exhibited higher levels of inflammatory mediators at the early stages of infection (≤24 hours) in WT mice than in TLR2(-/-) or MyD88(-/-) mice. However, their levels surpassed that of WT mice at the later stages of infection (>48 hours), coinciding with increased bacterial burden and retinal damage. Both TLR2(-/-) and MyD88(-/-) retinas produced reduced levels of CRAMP, and its deficiency (Cnlp(-/-)) rendered the mice susceptible to increased bacterial burden and retinal tissue damage as early as 1 day post infection. Analyses of inflammatory mediators and neutrophil levels in WT versus Cnlp(-/-) mice showed a trend similar to that observed in TLR2 and MyD88 KO mice. Furthermore, we observed that even a 10-fold lower infective dose of S. aureus was sufficient to cause endophthalmitis in TLR2(-/-) and MyD88(-/-) mice. CONCLUSIONS TLR2 and MyD88 signaling plays an important role in protecting the retina from staphylococcal endophthalmitis by production of the antimicrobial peptide CRAMP.
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Affiliation(s)
- Deepa Talreja
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University, Detroit, Michigan, United States Department of Biological Sciences, Oakland University, Rochester, Michigan, United States
| | - Pawan Kumar Singh
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University, Detroit, Michigan, United States Department of Anatomy and Cell Biology, Wayne State University, Detroit, Michigan, United States
| | - Ashok Kumar
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University, Detroit, Michigan, United States
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Yan Q, Sharma-Kuinkel BK, Deshmukh H, Tsalik EL, Cyr DD, Lucas J, Woods CW, Scott WK, Sempowski GD, Thaden J, Rude TH, Ahn SH, Fowler VG. Dusp3 and Psme3 are associated with murine susceptibility to Staphylococcus aureus infection and human sepsis. PLoS Pathog 2014; 10:e1004149. [PMID: 24901344 PMCID: PMC4047107 DOI: 10.1371/journal.ppat.1004149] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/12/2014] [Indexed: 01/21/2023] Open
Abstract
Using A/J mice, which are susceptible to Staphylococcus aureus, we sought to identify genetic determinants of susceptibility to S. aureus, and evaluate their function with regard to S. aureus infection. One QTL region on chromosome 11 containing 422 genes was found to be significantly associated with susceptibility to S. aureus infection. Of these 422 genes, whole genome transcription profiling identified five genes (Dcaf7, Dusp3, Fam134c, Psme3, and Slc4a1) that were significantly differentially expressed in a) S. aureus -infected susceptible (A/J) vs. resistant (C57BL/6J) mice and b) humans with S. aureus blood stream infection vs. healthy subjects. Three of these genes (Dcaf7, Dusp3, and Psme3) were down-regulated in susceptible vs. resistant mice at both pre- and post-infection time points by qPCR. siRNA-mediated knockdown of Dusp3 and Psme3 induced significant increases of cytokine production in S. aureus-challenged RAW264.7 macrophages and bone marrow derived macrophages (BMDMs) through enhancing NF-κB signaling activity. Similar increases in cytokine production and NF-κB activity were also seen in BMDMs from CSS11 (C57BL/6J background with chromosome 11 from A/J), but not C57BL/6J. These findings suggest that Dusp3 and Psme3 contribute to S. aureus infection susceptibility in A/J mice and play a role in human S. aureus infection.
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Affiliation(s)
- Qin Yan
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Batu K. Sharma-Kuinkel
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Hitesh Deshmukh
- Division of Neonatology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Ephraim L. Tsalik
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Emergency Medicine Service, Durham Veteran's Affairs Medical Center, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Derek D. Cyr
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Joseph Lucas
- Quintiles Innovations, Morrisville, North Carolina, United States of America
| | - Christopher W. Woods
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Section on Infectious Diseases, Durham Veteran's Affairs Medical Center, Durham, North Carolina, United States of America
| | - William K. Scott
- Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States of America
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, Florida, United States of America
| | | | - Joshua Thaden
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
| | - Thomas H. Rude
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Sun Hee Ahn
- Department of Biochemistry School of Dentistry, Chonnam National University, Bukgu, Gwangju, Korea
| | - Vance G. Fowler
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
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Hombrebueno JR, Luo C, Guo L, Chen M, Xu H. Intravitreal Injection of Normal Saline Induces Retinal Degeneration in the C57BL/6J Mouse. Transl Vis Sci Technol 2014; 3:3. [PMID: 24757593 DOI: 10.1167/tvst.3.2.3] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Accepted: 01/31/2014] [Indexed: 02/01/2023] Open
Abstract
PURPOSE To investigate the adverse effect of intravitreal injection of normal saline (NS) and phosphate buffered saline (PBS) in mouse eyes. METHODS NS or PBS was injected intravitreally into C57BL/6J mouse eyes. Retinal lesions were monitored by fundus imaging, spectral-domain optical coherence tomography (SD-OCT), and histological investigations. Retinal immune gene expression was determined by real-time polymerase chain reaction (PCR). The toxic effect of NS and PBS or retinal protein from NS- or PBS-injected eyes on retinal pigment epithelium (RPE) was tested in B6-RPE-07 mouse RPE cell cultures. RESULTS Intravitreal injection of NS dose-dependently induced localized retinal lesion in mice. Histological investigations revealed multiple vacuoles in photoreceptor outer segments and RPE cells. The lesions recovered over time and by 3 weeks post injection the majority of lesions vanished in eyes receiving 1 μl NS. Inflammatory genes, including TNF-α, IL-1β, IL-6, iNOS, and VEGF were upregulated in NS injected eyes. Intravitreal injection of PBS did not cause any pathology. The treatment of B6-RPE07 cells with 30% PBS or 30% NS did not affect RPE viability. However, incubation of 1-μg/ml retinal protein from NS-injected eyes, but not PBS-injected eyes induced RPE cell death. CONCLUSION NS is toxic to the C57BL/6J mouse retina and should not be used as a vehicle for intraocular injection. PBS is not toxic to the retina and is a preferred vehicle. TRANSLATIONAL RELEVANCE NS is not a physiological solution for intraocular injection in the C57BL/6J mice and questions its suitability for intraocular injection in other species, including human.
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Affiliation(s)
- Jose R Hombrebueno
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, UK
| | - Chang Luo
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, UK
| | - Linda Guo
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, UK ; School of Medicine, Imperial College of London, UK
| | - Mei Chen
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, UK
| | - Heping Xu
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, UK
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