The effect of paraffin wax embedding procedures on the ability of the fluorescent antibody test to demonstrate bluetongue virus antigen in insect tissue.

The effect of the reagents used in paraffin wax embedding procedures on the fluorescent antibody technique was investigated with a view to using this test for virus location studies on paraffin wax sections of bluetongue virus infected Culicoides variipennis. Experiments were carried out using tissue smears rather than prepared sections, enabling the effect of individual reagents to be evaluated. Infected smears treated with acetone alone showed bright specific fluorescence, while treatment of infected smears with all other reagents, including low melting point wax and acetone-soluble ester wax, prior to immunofluorescence testing reduced the brightness of specific fluorescence or rendered the test completely ineffective.