Experimental melanin protein-induced uveitis (EMIU)
EMIU is a T-cell mediated, bilateral, recurrent uveitis. EMIU is induced in the rat and the monkey by immunization with purified bovine ocular melanin protein. In EMIU, delayed-type hypersensitivity, lymphocyte proliferation, and agglutination to bovine ocular melanin and melanin-associated protein are positive. MHC class II antigens and adhesion molecules are expressed on ocular resident cells before ocular infiltration of T cells and macrophages. Unlike experimental autoimmune uveoretinitis (EAU) in the rat, anterior uveitis (iridocyclitis) is an important pathological feature and retinal involvement is observed only in some severe and/or recurrent cases of EMIU. Unlike endotoxin-induced uveitis (EIU) in the rat and mouse, a spontaneous recurrence occurs in about 1/4 cases of EMIU and recurrence can be easily induced with minimal dosages (5 micrograms) of lipopolysaccharide (LPS). The relapsing feature makes EMIU a practical model for the evaluation of therapies initiated during established disease and aimed at the prevention of recurrence. Thus, it more closely resembles certain forms of uveitis in humans.
|Many inflammatory cells infiltrate the iris (I), ciliary body (CB) and choroid (Ch). The cornea (Co) and retina (R) are free of disease.