Immunopathology Section

Endotoxin-induced uveitis (EIU)

Subcutaneous injection of a sublethal dose of lipopolysaccharide (LPS) can induce an acute, anterior uveitis (iridocyclitis) in certain animal species including rats, mice, and rabbits. The histopathology of EIU is characterized by a transient but intense acute inflammatory cellular infiltration of neutrophils and macrophages, as well as protein accumulation in the anterior chamber and mild posterior vitritis. EIU usually peaks at 18-24 hours after LPS injection and lasts for 72 hours. Various cytokines and chemokines released by the infiltrating cells, such as TNF-alpha, INF-gamma, TGF-beta, IL-1, IL-6, IL-8, CCL2, CCL5, and inflammatory mediators are important in the development and modulation of EIU. T cells also play a role in EIU. Multiple genetic factors influence the susceptibility and magnitude of the response to LPS, including (non-histocompatibility) genetic background, the LPS response gene, and the presence of mast cells. EIU has become a useful model for the study of acute and subacute anterior ocular inflammation in humans.

Photomicrograph of endotoxin-induceduveitis (EIU) in the C3H/HeN mouse

Healthy anterior segment
Image of healthy anterior segment

Anterior segment of mouse with EIU
Note inflammatory cells adhering to cornea and iris
Image of anterior segment of mouse with EIU