Lingual and major salivary tissue samples from three cases of rabies w
ere stained with the immunoperoxidase (ABC) technique. All tissue bloc
ks had been embedded in paraffin 4-10 years before. The first antibody
used was monoclonal antirabies nucleocapsin (N) mouse antibody (HAM).
Four out of five pieces of tongue from two cases showed a large amoun
t of granular staining indicating rabies antigen (RVAg) inside serous
glandular cells, terminal nerves, muscle cells and covering epithelial
cells including taste cells. In the tissue probes from the third case
only minimal granular staining was found, probably due to complete ab
sence of the serous gland. In contrast to the tongue, only a little we
akly reacting material was found in 4 out of 9 probes of salivary glan
d, either in acini or in nerve fibres. The amount of RVAg is evidently
much greater in the human tongue than in major salivary glands, where
as major salivary glands from infected clogs, foxes and skunks reporte
dly contain much RVAg. As the human tongue's serous gland appears to b
e a preferred location for RVAg it may be a source of oral infection.