The use of anti-PrP antibodies represents one of the most promising strategies for the treatment of prion diseases. In the present study, we screened various anti-PrP antibodies with the aim of identifying those that would block PrP Sc replication in prion-infected cell culture.

No abstract

Transmissible spongiform encephalopathies are characterized by the accumulation in brain tissues of an abnormal isoform of the prion protein named PrPsc, which is the only direct marker known for transmissible spongiform encephalopathies. Here we show that PrPsc can be specifically immunoprecipitated by using several monoclonal antibodies (mAbs) of various specificities independently of the properties of their binding site (paratope). These results strongly suggest that a significant proportion of mAbs can interact with PrPsc aggregates through nonspecific paratope-independent interactions allowing selective immunoprecipitation of PrPsc when these mAbs are immobilized on a polydisperse solid phase like microbeads.

Currently, there is no treatment to cure transmissible spongiform encephalopathies. By taking advantage of the `prion-resistant' polymorphisms Q171R and E219K that naturally exist in sheep and humans, respectively, we have evaluated a therapeutic approach of lentiviral gene transfer. Here, we show that VSV-G (vesicular stomatitis virus G glycoprotein) pseudotyped FIV-(feline immunodeficiency virus) derived vectors carrying the mouse Prnp gene in which these mutations have been inserted, are able to inhibit prion replication in chronically prion-infected cells. Because lentiviral tools are able to transduce post-mitotic cells such as neurons or cells of the lymphoreticular system, this result might help the development of gene- or cell-therapy approaches to prion disease.