Related Experiment Video
Updated: Sep 12, 2025
Author Spotlight: Exploring Retinal Regeneration Mechanisms in the Xenopus Frog
Published on: October 13, 2023
Development of a Targeted Choroidal Injury Model for the Study of Retinal Degenerations and Therapeutic Cell
Purpose:
Choroidal loss is an important pathophysiological step in many retinal diseases, but few reliable translational models of choroidal injury exist. Here, we report a new targeted choroidal injury model using bioconjugated saporins and compare it models of systemic sodium iodate administration.
Methods:
Wild-type Sprague-Dawley rats were given suprachoroidal injections of anti-CD38 or anti-CD105 antibodies conjugated to saporin immunotoxin (10 µl at 0.05 µg/µL) to induce selective choroidal endothelial cell injury. These animals were compared to wild-type rats given sodium iodate (75 mg/kg) via tail vein injections, with a dose escalation study (25, 50, and 75 mg/kg) in immunocompromised (Sprague-Dawley Rag2/Il2g double-knockout) rats. Animals were examined at 1-, 2-, and 3-weeks post-treatment, and the degree of choroidal injury compared using fundus photography, optical coherence tomography, and immunohistochemistry.
Results:
Suprachoroidal administration of anti-CD38 or anti-CD105 saporins resulted in severe choroidal vascular injury localized to the injection site, without damage to adjacent choroidal vasculature, progressive injury over time, or development of choroidal neovascularization. By contrast, sodium iodate treated animals had rapid, diffuse choroidal loss which progressed throughout the study time points, with fatal systemic side effects at the highest (75 mg/kg) dose.
Conclusions:
Suprachoroidal injection of anti-CD38 and anti-CD105 saporins results in targeted, localized, non-progressive choroidal injury in rats. These models offer alternatives to systemic sodium iodate administration, which causes diffuse, progressive choroidal injury.
Translational Relevance:
Immunotoxin-based models of targeted choroidal injury may be useful for understanding pathways of retinal degeneration and facilitating development of therapies for diseases involving choroidal cell loss.
Insights
New immunotoxin models provide targeted choroidal injury in rats, offering a localized alternative to systemic sodium iodate for studying retinal diseases.
Area of Science:
- Ophthalmology
- Retinal Diseases
- Choroidal Pathophysiology
Background:
- Choroidal loss is a key factor in many retinal diseases.
- Developing reliable translational models for choroidal injury is challenging.
Purpose of the Study:
- To report a novel targeted choroidal injury model using bioconjugated saporins.
- To compare this model with systemic sodium iodate administration models.
Main Methods:
- Rats received suprachoroidal injections of anti-CD38 or anti-CD105 saporin immunotoxins.
- Comparison with systemic sodium iodate administration in wild-type and immunocompromised rats.
- Choroidal injury assessed via fundus photography, OCT, and immunohistochemistry at 1, 2, and 3 weeks.
Main Results:
- Saporin immunotoxins caused localized choroidal vascular injury without affecting adjacent vasculature or causing neovascularization.
- Sodium iodate induced rapid, diffuse choroidal loss with systemic toxicity at higher doses.
- Saporin models showed non-progressive injury, unlike the diffuse, progressive injury from sodium iodate.
Conclusions:
- Suprachoroidal saporin injections create targeted, localized, non-progressive choroidal injury models in rats.
- These models serve as viable alternatives to systemic sodium iodate for studying choroidal injury.
- Immunotoxin models aid in understanding retinal degeneration and developing therapies for choroidal cell loss.
More Related Videos
07:46Author Spotlight: Advancing Vision Restoration - Stem Cell-Based Therapy for Retinal Diseases
Published on: October 6, 2023
11:03Subretinal Transplantation of Human Embryonic Stem Cell Derived-retinal Pigment Epithelial Cells into a Large-eyed Model of Geographic Atrophy
Published on: January 22, 2018