The use of monoclonal antibody epitopes for tagging PrP in conversion experiments

The key event in the pathogenesis of spongiform encephalopathies is a conformational transition of a normal cellular protein, PrPsen, to its pathological isoform, PrPres. The mechanism of PrPres formation is unknown but is likely to involve a direct interaction between PrPsen and PrPres. The molecular basis of PrPres formation has been studied extensively using transgenic mice and scrapie-infected tissue cultures that express heterologous PrP molecules. However, these experiments are dependant on the discrimination of endogenous host PrP and exogenous PrP molecules. Here we give a short review on the PrP-specific epitopes that have been used for tagging exogenous PrP molecules and present a novel PrP-specific epitope that is well suitable for in vivo and in vitro conversion experiments.