Prion Disease Therapy: Trials and Tribulations

Assessment of Prospective Preventive Therapies for Chronic Wasting Disease in Mule Deer

“…A vaccine or therapeutic compound preventing cervids from becoming infected with CWD would be a tremendous asset to disease management, especially one that could be easily delivered (e.g., via mineral licks or bait) and that had sustained effects that prevented new infections and reduced shedding in infected individuals. Several compounds showing some efficacy in preventing or retarding the progression of prion infection have been identified (Sim and Caughey, 2010). We tested three compounds that are readily available, have been shown to be safe, and have antiprion efficacy in vitro or in vivo: Pentosan polysulfate is a sulfated polysaccharide with anti-inflammatory properties that interferes with peripheral prion propagation; tannic acid is a naturally occurring polyphenol antioxidant; and tetracycline HCl is an antibiotic with prion-decontaminating properties (Ehlers and Diringer, 1984; Caughey and Raymond, 1993; Farquhar et al, 1999; Forloni et al, 2002; Kocisko et al, 2003; Raymond et al, 2006; Sim and Caughey, 2010).…”

“…From a population management standpoint, compounds that prevent or clear peripheral infection will be more useful than those targeting the central nervous system; from a practical standpoint, such compounds will likely need to be effective when delivered orally. Of the various prospects identified thus far, the large-molecule compounds like sulfated poly-saccharides and sulfated fucosylated poly-saccharides (Doh-ura et al, 2007), alone or in combination (Sim and Caughey, 2010), seem most promising for application to captive and free-ranging cervids. Seaweed fucoidan may deserve further attention in light of its apparent effects in delaying onset of scrapie in orally inoculated mice (Doh-ura et al, 2007).…”