Using immunohistochemical techniques, we analyzed the inflammatory cell subpopulation and the presence of fibronectin and immunoglobulin in iridectomy specimens from 50 patients with cataracts, glaucoma, and uveitis, and from ten normal eyes. The irises from patients with uveitis showed the highest numbers of T-lymphocytic infiltration compared with all other groups. Concentrations of fibronectin, fibrinogen, and immunoglobulins were significantly higher in the uveitic group compared with other diseases and normal controls. The irises from patients with glaucoma showed fewer infiltrating cells and less fibronectin and fibrinogen. Enhancement of major histocompatibility complex class II antigen HLA-DR expression was observed in all disease groups compared with controls. These findings suggest that in patients with uveitis and acute glaucoma the infiltrating T lymphocytes and the presence of fibronectin, fibrinogen, and immunoglobulins may contribute to the greater risk of postsurgical inflammation, leading to such problems as closure of the iridectomy. The enhancement of HLA-DR antigen expression in the iris may indicate abnormalities of iris resident cells seen in various diseases.