Soluble TNF receptors in vitreoretinal proliferative disease

PURPOSE. TO measure vitreous levels of soluble TNF-receptors (sTNF-Rs) type s I and II in eyes with rhegmatogenous retinal detachment (RRD), uncomplica ted or complicated with proliferative vitreoretinopathy (PVR), and in eyes with proliferative diabetic retinopathy (PDR). To examine whether there is any relationship between vitreous levels of sTNF-Rs and clinical features o f these conditions and between vitreous sTNF-Rs and TNF alpha levels and se rum levels of sTNF-Rs. METHODS. Vitreous levels of sTNF-Rs and TNF alpha were measured by enzyme-l inked immunosorbent assay in 30 eyes with PVR, 30 eyes with uncomplicated R RD, and 29 eyes with PDR. Vitreous from eyes of 10 deceased donors and 9 ey es with macular holes served as control specimens. Serum levels of sTNF-Rs were measured in 17 patients With PDR and 21 patients with PVR. RESULTS. Vitreous levels of sTNF-Rs I and II were increased in eyes with PV R, RRD, and PDR when compared with control eyes (P < 0.002). However, vitre ous levels of sTNF-Rs I and II were higher in eyes with PVR than in eyes wi th RRD (P < 0.01) or PDR (P < 0.03). This contrasted with the findings that serum sTNF-Rs were higher in PDR than in PVR (P < 0.016) and that vitreous levels of TNF alpha were higher in eyes with PDR than in eyes with PVR (P < 0.0005). In PVR, vitreous sTNF-Rs levels were associated with the duratio n of retinal detachment, number of previous external operations, and grade of severity, whereas in PDR these levels were not related to the type or du ration of diabetes or its complication with traction retinal detachment. CONCLUSIONS. These observations suggest the existence of TNF inhibitory mec hanisms within the eye during retinal processes of inflammation and angioge nesis. That high vitreous levels of sTNF-Rs relate to severity of retinopat hy suggests that these molecules may constitute reactive products of inflam mation. Effective control of TNF alpha activity by sTNF-Rs within the retin al microenvironment mag determine the outcome and severity of retinal proli ferative conditions.