Corneal keratocytes labelled by immunogold labelling for kappa light chain

Tissue fixed in 2.5% glutaraldehyde and 1% osmium tetroxide and embedded in epoxy resin. sections treated with saturated aqueous sodium metaperiodate for 1 hour before labelling and incubated overnight at 4^oC with rabbit polyclonal antibodies to kappa light chains. The promary antibody concentration was 375µg/ml (measured by single radial immunodiffusion) diluted to 1:200. Antibodies visualized with 10nm protein A-gold (A₅₂₀:0.126). Keratocytes contain intracellular fibrillar crystalloids that are kappa light chain positive. Original magnification x 22,000.