BACKGROUND: Immunohistological staining of the vitreous is difficult because of its high water content. We present a method for immunohistological staining of celloidin-embedded eyes. Results from diabetic and non-diabetic eyes are demonstrated. METHOD: Diabetic and non-diabetic eyes were firstly immersed in formol and then slowly dehydrated using rising concentrations of glycerine (sink method). Subsequently, the whole globe was embedded in celloidin and cut into 200-micron sections. Control areas of interest were dissected from the 200 microns sections under a lightmicroscope. These specimens were then embedded in paraffin and cut into 7-micron sections. The 7-micron sections were immunohistochemically stained for type I-collagen, type IV-collagen, fibronectin and laminin. RESULTS: This method makes immunohistochemical staining of the vitreous possible. Type IV collagen, laminin and fibronection were found at higher concentrations in diabetic eyes than in normal eyes. Type I collagen was detected in neither diabetic nor in normal eyes. CONCLUSIONS: Our method of examination allows immunohistological staining of the vitreous in its place of origin. Although our method is time consuming, it has some advantages over biochemical analysis: Even minimal changes and their exact distribution can be detected. Our first results show that the vitreous is built up inhomogeneously and that pathological influence can cause structural changes.
BACKGROUND: Immunohistological staining of the vitreous is difficult because of its high water content. We present a method for immunohistological staining of celloidin-embedded eyes. Results from diabetic and non-diabetic eyes are demonstrated. METHOD:Diabetic and non-diabetic eyes were firstly immersed in formol and then slowly dehydrated using rising concentrations of glycerine (sink method). Subsequently, the whole globe was embedded in celloidin and cut into 200-micron sections. Control areas of interest were dissected from the 200 microns sections under a lightmicroscope. These specimens were then embedded in paraffin and cut into 7-micron sections. The 7-micron sections were immunohistochemically stained for type I-collagen, type IV-collagen, fibronectin and laminin. RESULTS: This method makes immunohistochemical staining of the vitreous possible. Type IV collagen, laminin and fibronection were found at higher concentrations in diabetic eyes than in normal eyes. Type I collagen was detected in neither diabetic nor in normal eyes. CONCLUSIONS: Our method of examination allows immunohistological staining of the vitreous in its place of origin. Although our method is time consuming, it has some advantages over biochemical analysis: Even minimal changes and their exact distribution can be detected. Our first results show that the vitreous is built up inhomogeneously and that pathological influence can cause structural changes.