Ocular fundus lesions in systemic lupus erythematosus model mice

We investigated the ocular fundus of (NZWXBXSB) F1 mice, which are considered to be a good model for systemic lupus erythematosus (SLE) with antiphospholipid syndrome. The abnormal fundus findings were documented by fundus photography, and the chorioretinal lesions were studied histopathologically. The incidence of ocular fundus abnormalities and systemic signs in these F1 mice was significantly higher in males than in females, as with the systemic symptoms. This indicated an influence of the Yaa (Y chromosome-linked autoimmune acceleration) gene. Lesions in the fundus appeared as white spots, which increased in number during the course of the disease and developed into retinal detachment in some animals. This developmental course resembled the course of patients with multifocal posterior pigment epitheliopathy. Dilatation of the veins and narrowing of arteries were marked. Histopathological findings included: (1) destruction of the photoreceptor cell layer, (2) degeneration and loss of the retinal pigment epithelium, (3) thickening of the wall of the choroidal arterioles, and (4) narrowing and occlusion of the choriocapillaris associated with hyaline degeneration and thrombus formation. The study of the SLE mouse model should contribute to the understanding of the abnormalities in the fundus associated with collagen diseases.