Effect of routine paraffin wax processing on cell membrane immunoreactivity in cutaneous tissue

The effects of the sequential stages of paraffin wax embedding on immunolabelling of cutaneous cell membrane antigens by monoclonal antibodies are described. Modifications in incubation times for fixation, dehydration, clearing and wax embedding of sections were examined. Labelling of the cell surface antigens deteriorates only after formal saline fixation for a period longer than 4 hr. Dehydration in ethanol had a minor adverse influence but clearing in xylene diminished immunoreactivity markedly. Both deleterious effects could be circumvented by conducting the procedures at 4 degrees C. The wax embedding procedure at 58 degrees C adversely affected labelling after 1 hr.