NR AXZC
AU Xanthopoulos,K.; Kyratsous,C.; Lagoudaki,R.; Bloukas,G.; Grigoriadis,N.; Panagiotidis,C.; Sklaviadis,T.
TI Immunization Against PrP and Fusion PrP Recombinant Peptides
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Protein Misfolding P01.25
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
Immunization against prions has been attempted in several animal models. However, the low immunogenicity of this molecule in wild type (wt) animals has hampered the attempts for active immunogenization. In this study we aimed to evaluate the immunogenicity of various forms of mouse recombinant PrP (mrPrP) in wt mice and their possible protective role in an animal model of transmissible spongiform encephalopathies (TSEs).
Murine PrP was cloned and expressed either alone or fused to the heat shock protein DnaK, a bacterial homologue of human HSP70. The recombinant proteins were administered to groups of mice (c57bl/6); the first group received purified mrPrP, solubilized in urea, the second purified mrPrP inclusion bodies, solubilized in a mild detergent solution. The third group received the mrPrP-DnaK fusion, whereas a mix of solubilized mrPrP and recombinant DnaK were administered to the fourth group. A group that received the adjuvant only and a group which was not immunized were also included. The immunization scheme consisted in priming and two boosts, with 14 days intervals. 10 days after the second boost, the anti-mrPrP titer was estimated by ELISA and Western blotting (WB). The mice were then challenged intraperitoneally with the RML scrapie strain and observed for the appearance of clinical symptoms. When the mice reached terminal stage they were sacrificed and their tissues prepared for immunohistochemistry and WB. On at least two mice of each group splenic lymphocytes were harvested and lymphocyte proliferation assays, as well as RT-PCR analysis of the expression of Il-2, Il-4, Il-6 and Ifn-g genes in the cultured lymphocytes in the presence of mrPrP were performed.
Data from the ELISA and WB analysis indicate that only mice that received the mix of mrPrP and DnaK mounted a measurable immune response against mrPrP. Anti-serum from one of these mice also recognized PrPc in whole murine brain homogenates, but not purified PrPsc. However mice that received the solubilized purified inclusion bodies succumbed to disease later than the other mice. Results form the cell proliferation assay and the RT-PCR analysis indicate the elicitation of cell mediated immune response.
Our data are also indicative that protection against TSEs does not necessarily correlate with the stimulation of production of anti-PrP antibodies and that the administration of mrPrP inclusion bodies could prove an effective immunization procedure.
AD K. Xanthopoulos, G. Bloukas, C. Panagiotidis, T. Sklaviadis, Aristotle University of Thessaloniki, Department of Pharmaceutical Sciences, Greece; C. Kyratsous, College of Physicians and Surgeons, Columbia University, Department of Microbiology, USA; R. Lagoudaki, N. Grigoriadis, AHEPA University Hospital, Aristotle University of Thessaloniki, B Department of Neurology, Greece
SP englisch
PO Schottland