Detection of species specific epitopes of mouse and hamster prion proteins (PrPs) by anti-peptide antibodies.

Antisera to four synthetic peptides containing the substitutions between mouse and hamster prion proteins (PrPs) were produced in rabbits. The synthetic peptides used represent two mouse (Mo-I: residues 100-115 and Mo-V: residues 199-208) and two hamster PrP subregion sequences (Ha-I: 101-116 and Ha-V: 200-209). All antisera reacted strongly with homologous peptides but either not at all or poorly with heterologous peptides in enzymelinked immunosorbent assay (ELISA). Antisera to Mo-I and Mo-V recognized mouse PrPSc but not hamster PrpSc in western blot analysis (WB) and ELISA. Antisera to Ha-I contain antibodies specific to hamster PrPSc. The results indicate that these regions of PrPSc constitute species-specific epitopes. In contrast to these antisera, the antiserum to Ha-V recognized neither hamster nor mouse PrPSc. In this study, we identified mouse subregion-V as a species-specific epitope.