[The immunosuppressive acidic protein in the vitreous of fundus diseases]

Immunosuppressive acidic protein (IAP) is known to be a useful marker for malignant tumors and inflammatory diseases. We have previously reported that serum IAP level was increased in cases of Behçet's disease, especially in the acute phase, and those of retinoblastoma with extraocular infiltration. We assayed IAP levels in the vitreous body of various ocular diseases, including five cases of proliferative vitreoretinopathy (PVR), five cases of vitreous hemorrhage including four cases of branch retinal vein occlusion (BRVO) and one case of Terson's syndrome, four cases of proliferative diabetic retinopathy (PDR) and five cases of acute retinal necrosis syndrome. The single radial immunodiffusion method was used. The vitreous IAP level ranged from 5 to 130 micrograms/ml according to each case. Statistical analysis revealed that the vitreous IAP level was significantly higher in the group of PDR (p less than 0.05) and in the group of acute retinal necrosis syndrome (p less than 0.01) compared to the group of vitreous hemorrhage. In all cases, serum IAP levels were within normal limits. These results suggested that IAP might be produced within the ocular tissue, possibly by the activation of suppressor macrophages and migration of polymorphonuclear leukocytes in the vitreous with pathologic condition.