Immunohistochemical Study of Periretinal Memberanes in Proliferative Vistreoretinopathy

We Performed an immunohistochemical study to identify the cellular components and involvement of immune mechanism in proliferative vitreoretinopathy, which is a major cause of delayed filure of retinla surgery. The 17 specimens of periretinal membranes -including vitreal membranes- were surgically obtained during the pars plana vitrectomy. The clinical diagnoses were idiopathic or traumatic retinal detachment (9 eyes), proliferative diabetic retinopathy (6 eyes), and pars plannitis (2 eyes). The labeled streptavidin-biotin immunoperoxidase method was used for immunohistochemical stain. The following antigens were detected in periretinal membranes : cytokeratin in 8 (of 17 cases studied for this antigen), glial fibrillary acidic protein (GFAP) in 9 (of 17), vimentin in 15 (of 17), HLA-DR in 14 (of 17). The macrophages and T lymphocyte expressing CD4 or CD8 markers, were not found in any of the membranes. These results suggest that cellular components of periretinal membranes are consists of retinal pigment epithelial cells, glial cells, and fibroblast. The identification of macrophage and T lymphocytes all met with failure. Also, strong positivity of HLA-DR antigen may indicate involvement of the immune mechanism during the course of proliferative vitreoretinopathy.

Immunohistochemical Study of Proliferative Vitreoretinal Membranes

To identify the cellular components of proliferative vitreoretinal membranes. 11 proliferative vitreoretinal membranes which were surgically obtained from 7 eyes with proliferative vitreo retinopathy (PVR) and 4 eyes with proliferative diabetic retinopathy (PDR) were stained with monoclonal antibodies against cytokeratin, glial fibrillary acidic protein(GFAP), or vimentin using immunoperoxidase technique (ABC method). In PVR membranes, mean cell positivities for cytokeratin, GFAP and vimentin were 48%, 1% and 92%, respectively and in PDR membranes, 0%, 5% and 93%, respectively. The above results suggest that retinal pigment epithelial celIs and fibroblasts are major cellular components of PVR membranes, and mesenchymal cells are major cellular components and glial cells minor cellular components of PDR membranes.

Cellular components of proliferative vitreoretinal membranes

To understand the pathogenesis of proliferative vitreoretinal membrane formation which occurs in proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR), etc., accurate identification of the cellular components of the membrane is needed. This study was performed to identify cellular components of the membranes by means of immunohistochemical technique. 11 proliferative vitreoretinal membranes which were surgically obtained from 7 eyes with PVR and 4 eyes with PDR were stained with monoclonal antibodies against cytokeratin, glial fibrillary acidic protein (GFAP), or vimentin using immunoperoxidase technique (ABC method). In the PVR membranes, mean cell positivities for cytokeratin, GFAP and vimentin were 48%, 1% and 92%, respectively and in the PDR membranes, 0%, 5% and 93%, respectively. The above results suggest that retinal pigment epithelial cells and fibroblasts are major cellular components of PVR membranes, and that mesenchymal cells are major cellular components and glial cells are minor cellular components of PDR membranes.