PSEUDO‐EXFOLIATION FIBRILS EXAMINED BY NEGATIVE STAINING

Abstract

Pseudo-exfoliation (PE) material, collected from lenses [human] extracted because of cataract, was examined by negative staining [and EM]. The material was fragmented by ultrasound into single fibrils and small collections of fibrils. The fibrils were composed of a small number of filamentous subunits associated with or surrounded by a fuzzy material which had side excrescences at regular intervals of 50-55 nm or 25-30 nm. The side excrescences correspond to the cross-bands of the PE fibrils. Apparently the PE fibrils are composed of a few subunits of a fibrillar protein, which form a core to which glycosaminoglycan side chains are attached. The visible periodicity of the PE fibrils, appearing as cross-bands, may be caused by clusters of glycosaminoglycan distributed at regular intervals along the fibrils.