Immunohistochemical study of vascular endothelial growth factor VEGF, tumor suppressor protein p53 and intercellular adhesion molecule ICAM in the conjunctiva of diabetic patients without retinopathy

Abstract

Abstract: : Purpose: A correlation between VEGF, p53 and ICAM has been implicated in the development of angiogenesis in diabetic retinopathy (DR). Our purpose was to study the expression of these proteins in the conjunctiva of diabetic patients without DR Methods: All patients underwent a complete ophthalmic examination including fluorescein angiography. We excluded patients with any fibrovascular ocular or general pathology. Indirect immunoperoxidase method was performed on 20 eyes without DR and diabetes type 2 less than 15 years. We used monoclonal antibodies against p53 and ICAM and polyclonal antibody against VEGF. Control study was performed on 6 normal conjunctiva undertaken during cataract surgery . Results: Immunoreactivity of VEGF, p53 and ICAM protein was found in epithelial cells, fibroblast cells, vascular endothelial cells and infiltrating cells. For the same duration of diabetes, a strong to moderate immunoreactivity was observed in patients. Further, the immunoreactivity was correlated for VEGF, p53 and ICAM. In the normal conjunctiva, a weak to negative immunostaining and localized mainly to the basal cells was observed. Conclusions: A different profile of expression of these proteins was found for the same duration of diabetes. Immunohistochemical study of angiogenic factors in the conjunctiva of diabetic patients may be helpful and useful to predict the activity of DR. These hypotheses need and require well designed clinical studies.

Keywords: conjunctiva • diabetes • immunohistochemistry