Cationic phosphorus-containing dendrimers reduce prion replication both in cell culture and in mice infected with scrapie.

Over the last 30 years, many drugs have been tested both in cell culture and in vivo for their ability to prevent the generation of prions and the development of transmissible spongiform encephalopathies. Among the compounds tested, dendrimers are defined by their branched and repeating molecular structure. The anti-prion activity of new cationic phosphorus-containing dendrimers (P-dendrimers) with tertiary amine end-groups was tested. These molecules had a strong anti-prion activity, decreasing both PrP(Sc) and infectivity in scrapie-infected cells at non-cytotoxic doses. They can bind PrP and decrease the amount of pre-existing PrP(Sc) from several prion strains, including the BSE strain. More importantly, when tested in a murine scrapie model, the dendrimers were able to decrease PrP(Sc) accumulation in the spleen by more than 80 %. These molecules have a high bio-availability and therefore exhibit relevant potential for prion therapeutics for at least post-exposure prophylaxis.