Rapid prion neuroinvasion following tongue XXXX .

@entity1 @entity129 @entity75 @entity344 @entity281 @entity3669
Food-borne transmission of prions can lead to @entity344 . Here we report that the transmission of @entity75 ( @entity75 ) is 100,000-fold more efficient by inoculation of prions into the tongues of hamsters than by oral ingestion. The incubation period following @entity75 agent (hereinafter referred to as @entity75 ) inoculation into the lingual muscles was the shortest among the five nonneuronal routes of inoculation, including another intramuscular route. Deposition of the abnormal isoform of the prion protein, @entity3669 (Sc), was first detected in the tongue and submandibular lymph node at 1 to 2 weeks following inoculation of the tongue with @entity75 . @entity3669 (Sc) deposits in the tongue were associated with individual axons, and the initial appearance of @entity75 in the brain stem was found in the hypoglossal nucleus at 2 weeks postinfection. At later time points, @entity3669 (Sc) was localized to brain cell groups that directly project to the hypoglossal nucleus, indicating the transneuronal spread of @entity75 . @entity75 @entity3669 (Sc) entry into the brain stem preceded @entity3669 (Sc) detection in the rostral cervical spinal cord. These results demonstrate that @entity75 can replicate in both the tongue and regional lymph nodes but indicate that the faster route of brain invasion is via retrograde axonal transport within the hypoglossal nerve to the hypoglossal nucleus. Topical application of @entity75 to a superficial wound on the surface of the tongue resulted in a higher incidence of disease and a shorter incubation period than with oral @entity75 ingestion. Therefore, abrasions of the tongue in livestock and @entity1 may predispose a @entity129 . In a related study, @entity3669 (Sc) was detected in tongues following the intracerebral inoculation of six hamster-adapted prion strains, which demonstrates that prions can also travel from the brain to the tongue in the anterograde direction along the tongue-associated cranial nerves. These findings suggest that food products containing ruminant or cervid tongue may be a potential source of prion @entity281 for @entity1 .
