MONOCLONAL-ANTIBODY F89 160.1.5 DEFINES A CONSERVED EPITOPE ON THE RUMINANT PRION PROTEIN/

The transmissible spongiform encephalopathies are a heterogeneous grou p of fatal neurodegenerative disorders occurring in humans, mink, cats , and ruminant herbivores. The occurrence of novel transmissible spong iform encephalopathies in cattle in the United Kingdom and Europe and in mule deer and elk in parts of the United States has emphasized the need for reliable diagnostic tests with standardized reagents. Postmor tem diagnosis is performed by histologic examination of brain sections from affected animals. The histopathological criteria for transmissib le spongiform encephalopathies include gliosis, astrocytosis, neuronal degeneration, and spongiform change. These lesions vary in intensity and anatomic location depending on the host species and genetics, stag e of disease, and infectious agent source. Diagnosis by histopathology alone may be ambiguous in hosts with early cases of disease and impos sible if the tissue is autolyzed. Deposition of the prion protein (an abnormal isoform of a native cellular sialoglycoprotein) in the centra l nervous system is a reliable marker for infection, and immunohistoch emical detection of this marker is a useful adjunct to histopathology. In the present paper we describe monoclonal antibody (MAb) F89/160.1. 5, which reacts with prion protein in tissues from sheep, cattle, mule deer, and elk with naturally occurring transmissible spongiform encep halopathies. This MAb recognizes a conserved epitope on the prion prot ein in formalin-fixed, paraffin-embedded sections after hydrated autoc laving. MAb F89/160.1.5 will be useful in diagnostic and pathogenesis studies of the transmissible spongiform encephalopathies in these rumi nant species.