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Updated: Jul 5, 2026
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Intravitreal Injection and Quantitation of Infection Parameters in a Mouse Model of Bacterial Endophthalmitis
Published on: February 6, 2021
High-mobility group box 1 protein in endophthalmitis
Noboru Arimura1, Yuya Ki-I, Teruto Hashiguchi
1Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima 890-8520, Japan.
Summary
High-mobility group box 1 protein (HMGB1) is elevated in endophthalmitis, suggesting it acts as a late mediator. Higher HMGB1 levels correlate with disease severity and poorer visual outcomes in this eye inflammation.
Area of Science:
- Ophthalmology
- Immunology
- Molecular Biology
Background:
- High-mobility group box 1 protein (HMGB1) is a known proinflammatory mediator.
- HMGB1's role in ocular inflammation, specifically endophthalmitis, was previously undetermined.
Purpose of the Study:
- To investigate the involvement of HMGB1 in endophthalmitis.
- To determine if HMGB1 levels correlate with disease severity and visual outcomes.
Main Methods:
- Retrospective case-control study comparing HMGB1 vitreous levels in endophthalmitis patients (n=10) versus controls (n=12).
- Vitreous HMGB1 measured using enzyme-linked immunosorbent assay (ELISA).
- Immunohistochemistry performed on ocular tissue samples to localize HMGB1 expression.
Main Results:
- Vitreous HMGB1 levels were significantly higher in endophthalmitis patients compared to controls (13.96 ng/ml vs. 0.236 ng/ml, P = .0006).
- HMGB1 levels showed significant correlations with disease duration, presenting visual acuity, and final visual acuity.
- Immunohistochemistry revealed diffuse HMGB1 expression in the retina and choroid of the endophthalmitis eye, particularly in inflammatory infiltrates.
Conclusions:
- HMGB1 is released into the vitreous during endophthalmitis, associated with inflammation and tissue damage.
- HMGB1 may function as a late mediator in endophthalmitis.
- HMGB1 levels appear related to the progression and severity of endophthalmitis.
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