Viral antigen distribution in organs of cattle experimentally infected with rinderpest virus.

The distribution of viral antigen in various organs of four approximately 10-month-old castrated male Friesian cattle experimentally infected with a highly virulent strain of rinderpest virus was studied. A monoclonal antibody with genus-specific reactivity for morbilliviruses was applied in an indirect immunoperoxidase method performed on formalin-fixed, paraffin-embedded tissue sections. Rinderpest viral antigen was located mainly in the cytoplasm of the epithelial cells of the digestive, respiratory, and urinary tracts, as well as in the cells of endocrine glands (adrenal, thyroid) and exocrine glands (salivary glands, sebaceous glands, exocrine pancreas). Furthermore, different types of cells in lymphatic organs contained rinderpest viral antigen. In contrast to the documented results of studies carried out with other morbilliviruses, tissues of the central nervous system did not contain viral antigen. Various types of epithelial and lymphoreticular cells are the main targets of a virulent strain of rinderpest virus in vivo.