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The expression of intercellular adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) were studied in the conjunctiva of diabetic patients with and without retinopathy. All patients underwent a complete ophthalmic examination including ocular fundus and retinal fluorescein angiography. The indirect immunoperoxidase method was performed on 15 normal conjunctivas taken during cataract surgery (group 1), on 40 eyes of 40 patients with type 2 diabetes without diabetic retinopathy (DR) (group 2) and 13 eyes of 13 patients with DR (group 3). ICAM-1 and VCAM-1 are located in epithelial cells, vascular endothelial cells and in stromal cells. Our results show a statistically significant increase in the immunohistochemical expression of these proteins in the conjunctiva of diabetic patients with and without DR in comparison with normal conjunctiva (P = 0.001). Noteworthy, ICAM-1 and VCAM-1 are upregulated in the conjunctiva of diabetic patients with and without retinopathy, reflecting the inflammatory nature of this condition and suggesting a possible role for these mediators in the pathogenesis of diabetic microangiopathy.

Introduction: Apoptosis, or programmed cell death, is necessary to multicellular organism survival, in contrast to involuntary necrosis that is devastating for tissue. It is positively or negatively regulated by proteins of the Bcl-2 family. The aim of our study was to analyze the expression of apoptotic factors Bax and Bcl-2 in the bulbar conjunctiva of diabetic patients without retinopathy and to compare it to the expression of these factors in nondiabetic patients., Material and Methods: Twenty-five conjunctival biopsies were obtained from diabetic patients without retinopathy. The ocular fundus and retinal fluorescein angiography results were normal. Normal human conjunctiva was taken from 15 patients undergoing senile cataract surgery. Immunohistochemical analysis was performed using indirect immunoperoxidase with antibodies against Bax and Bcl-2., Results: In the human diabetic conjunctiva, The Bax protein was highly expressed in all specimens (100%). It was distributed in epithelial cells, vascular endothelial cells, fibroblasts, and inflammatory cells. The Bcl-2 protein was always at a low level or absent. In normal conjunctiva, Bax showed a significant level, whereas Bcl-2 showed no trace of positivity., Conclusion: Bax is often localized in tissues characterized by an elevated rate of apoptosis; in contrast, Bcl-2 is absent in these places. Our results suggest that diabetic human conjunctiva, with its inflammatory and cicatricial phenomena, is a privileged target for apoptotic cell death.

Purpose: Recent research has incriminated adhesion molecules in the pathogenesis of diabetic retinopathy. These molecules have been found to be expressed in many cells participating in inflammatory processes and neovascularization. The purpose of our investigation was to study the expression of intercellular adhesion molecule type 1 (ICAM-1) in the conjunctiva of diabetic patients without retinopathy in comparison with normal human conjunctiva., Patients and Methods: Fifteen conjunctival biopsies were obtained from diabetic patients without retinopathy. The ocular fundus examination and retinal fluorescein angiography were normal. The normal human conjunctiva were taken from five patients undergoing senile cataract surgery. Immunohistochemical analysis consisted of indirect immunoperoxidase using the monoclonal antibody ICAM-1., Results: The adhesion molecule ICAM-1 was immunolocalized in epithelial, vascular endothelial, and inflammatory cells. The expression of this molecule was different in diabetic patients for the same duration. In the normal human conjunctiva, the expression of ICAM-1 was very low., Conclusion: This preliminary study shows that ICAM-1 is present in the conjunctiva of diabetic patients without retinopathy and thus may add new insights into the pathogenesis of diabetic retinopathy.

The expression pattern of VEGF, p53 and ICAM-1 was studied in conjunctiva of diabetic patients with and without retinopathy. All patients underwent a complete ophthalmic examination, including retinal fluorescein angiography. Indirect immunoperoxidase method was performed on 20 eyes of 20 patients with type II diabetes without DR and on 5 eyes of 5 patients with PDR. A control study was performed on 6 normal conjunctiva undertaken during cataract surgery. Immunoreactivity of VEGF, p53 and ICAM-1 was found in epithelial, fibroblast and vascular endothelial cells. For the same duration of diabetes, a strong to moderate or weak immunoreactivity was observed in the conjunctiva of patients without retinopathy. In patients with PDR, the expression was strong for all these proteins. The immunoreactivity was correlated between VEGF, p53 and ICAM-1. In the normal conjunctiva, a weak to negative immunostaining was observed. The presence of these proteins in the conjunctiva of diabetic patients without retinopathy may add new data in the pathogenesis of diabetic retinopathy. Further studies are needed to confirm this hypothesis.

Abstract: A pterygium is characterized by abnormal fibrovascular corneoconjunctival tissue. A number of investigations have attempted to elucidate this incompletely understood pathology. Since vascular endothelial growth factor (VEGF) and p53 are known to participate in tumor vascularization, our purpose was to study VEGF and p53 expression in active primary and recurrent pterygium from Tunisian patients. To this end, 15 cases of active primary pterygium and five cases of recurrent pterygium from Tunisia were studied by immunohistochemistry. Antibodies raised against VEGF and p53 were used to analyze the distribution and expression of these markers in pterygium and normal human conjunctiva were used as negative control. VEGF and p53 proteins were found in all cases of primary pterygium in epithelial, fibroblast and vascular endothelial cells. Active primary and recurrent pterygium have different patterns of expression. In primary pterygium, an important variability of p53 and VEGF expression was observed. However, in recurrent pterygium, p53 immunoreactivity was weak to moderate, whereas VEGF immunoreactivity was strong. In normal human conjunctiva, VEGF and p53 expression was weak to negative. The overexpression of VEGF in active primary and recurrent pterygium suggests that angiogenesis may play a role in pterygium pathogenesis and the expression of p53 in active primary pterygium, which might be associated with its mutated form, supports the hypothesis that actinic radiation may be involved in the genesis of pterygium. Thus, VEGF and p53 may be useful biomarkers for understanding the physiopathology of pterygium. [Copyright &y& Elsevier]