Recognition of PrP on the cell surface.

<p>Transgenic DT40 cells expressing PrP on their surface were stained with sera from 4 mice immunized with agPrP+FA (red, green, purple and cyan histograms) (A) or from 6 mice immunized with sPrP+DnaK+FA (red, green, purple, cyan, orange and brown histograms) (B), to evaluate recognition of PrP on the cell surface. Indigo; 6H4 staining, red negative control (secondary antibody only). Differences in the modes of the histograms between agPrP+FA and sPrP+DnaK+FA mice are statistically significant (T-test, P = 0.330).</p

Sera from sPrP+DnaK mice recognize total PrPSc and sPrP in western blots.

<p>A. 2.5 mg brain equivalent from terminally ill mice were blotted with 6H4 (lanes 1, 2), serum from a mouse immunized with sPrP+DnaK (lanes 3, 4) or with the secondary antibody alone (lanes 5, 6), prior (lanes 1, 3, 5) or ensuing (lanes 2, 4, 6) PrP^Sc enrichment. B. sPrP (1 µg) was blotted with serum from a mouse immunized with sPrP+DnaK (lane 7) or the secondary antibody alone (lane 8).</p

Survival curves of immunized mice.

<p>Naive mice and mice immunized with sPrP+FA, agPrP+FA, PrP-DnaK+FA, sPrP+DnaK+FA or FA alone were challenged with a mouse adapted scrapie strain and sacrificed at terminal point. Mice immunized with agPrP+FA survive significantly longer than naive mice (Mantel-Cox test, P = 0.0033).</p

sPrP is recognized with the immune sera in ELISAs.

<p>Sera from mice immunized with sPrP+FA, sPrP+DnaK+FA, PrP-DnaK+FA. agPrP+FA or FA alone were tested for their ability to recognize sPrP in ELISA in a 1∶100 (<i>v/v</i>) dilution. Each point corresponds to one individual. Line: average value; dotted line OD₄₀₅. of the positive control antibody (6H4, 0.2 µg/ml).</p

Splenic PrP^Sc accumulation.

<p>Early PrP^Sc accumulation in spleens from naive mice (lane 1), mice immunized with FA alone (lane 2), agPrP alone (3) or agPrP+FA (4), 40 (A) or 80 (B) days after challenge. Splenic samples from 3 mice per group were enriched in PrP^Sc and blotted with the polyclonal antibody SAL 1 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0059143#pone.0059143-Sachsamanoglou1" target="_blank">[39]</a>. Equal amounts of total protein from three mice per group were processed.</p