Figure 4.

Immunization of reindeer with dimeric recombinant PrP induces anti-PrP antibodies. A, seven reindeer were vaccinated three times with either Mdi (four animals) or Ddi (three animals) immunogens at 4-week intervals (one priming and two booster doses), and blood sampling was performed either before starting vaccination (preimmune) or 21 days after the second booster dose (post-immune). B, ELISA for post-immune sera of the Mdi-vaccinated reindeer (1:100 dilution shown), compared with the respective preimmune sera. The y axis represents the optical density (405 nm). C, both mouse and deer monomeric recombinant PrP were subjected to immunoblot analysis. As primary antibodies, the preimmune sera (reindeer ID: 15S) and post-immune sera of reindeer vaccinated with Mdi (reindeer ID: 15S) or Ddi (reindeer ID: 3WD) immunogens with comparable post-immune antibody titers, all in 1:500 dilution, were used.