Prion Digestion in the Alimentary Tract

Nicholas Toney

Overview

Outline of the Digestive Tract

Dr. Manuelidis’s Claims

Experimental Procedure

Discussion

Ruminant Digestion

Digestion

Claim to Brain

Manuelidis’s Claim:

All detectable forms of PrP are digested in the gastro intestinal tract yet the invasive infectious particle (as many conventional viruses) is not destroyed

Transportation of prion protein across the intestinalmucosa of scrapie-susceptible and scrapie-resistant sheep

Experimental Methods and Goals

In Vivo GI inoculation

In Vitro GI digestion of infectious brain slurry

Western Blot

Infectivity of Scrapie Prion Protein (PrPSc) Following In vitroDigestion with Bovine Gastrointestinal Microbiota Goals

Methodology

In Vitro Digestion

In Vivo determined level of infectivity

Discussion

Acid Resistance of Prions, digestion by microbiota

What limitations are there with the experimental methods?

Are the in-vitro digestion experiments a good model of digestion?

How do you reconcile the loss of detectable PrPres with the continued infectivity of brain slurry from Scrapie infected brain material?