Immunohistochemical detection of hog cholera virus antigen in paraffin wax-embedded tissues from naturally infected pigs.

In 17 pigs submitted for diagnosis in 1980, hog cholera was confirmed by viral isolation, by a direct immunofluorescent antibody test for viral antigen, and by the presence of characteristic histopathological lesions. In the present study, hog cholera viral antigen was demonstrated in these pigs by immunohistochemical examination of formalin-fixed paraffin wax-embedded tissues that had been stored for 18 years. Viral antigen was detected in crypt epithelial cells of the tonsil, collecting tubular epithelial cells of the kidney, bronchial and bronchiolar mucosal and gland cells of the lung, and pancreatic epithelial cells.