Effect of leukopenia on experimental post-traumatic retinal detachment

Area of Science:

• Ophthalmology
• Immunology
• Regenerative Medicine

Background:

• Macrophages are consistently found in intraocular membranes of patients with traumatic proliferative vitreoretinopathy (PVR).
• Recruitment of these macrophages can originate from adjacent tissues or systemic circulation.
• The specific role of circulating immune cells in PVR pathogenesis requires further elucidation.

Purpose of the Study:

• To investigate the role of circulating white blood cells and monocytes in experimental traumatic PVR.
• To determine if reducing circulating immune cells impacts the development of PVR-induced retinal detachment.

Main Methods:

• Twenty rabbits underwent leukopenia induced by intravenous strontium-89 injection.
• Posterior perforating eye injury followed by intravitreal injection of autologous whole blood or activated macrophages was performed.
• Incidence and severity of retinal detachment were assessed in leukopenic and control animals.

Main Results:

• Severe bone marrow depression significantly reduced retinal detachment incidence in eyes receiving whole blood.
• Reduced severity of retinal detachment was observed in eyes injected with activated macrophages in leukopenic animals.
• A direct association was found between the degree of leukopenia/monocytopenia and protection from retinal detachment.

Conclusions:

• Macrophage infiltration from the systemic circulation is a significant factor in intraocular cellular proliferation during PVR.
• Reducing circulating monocytes and white blood cells offers protection against retinal detachment in experimental PVR.
• While macrophages play a key role, other white blood cells may also contribute to PVR pathogenesis.