NR AXZT
AU Zuber,C.; Knackmuss,S.; Rey,C.; Pace,C.; Mitteregger,G.; Reusch,U.; Fröhlich,T.; Arnold,G.J.; Hallek,M.; Büning,H.; Kretzschmar,H.A.; Little,M.; Weiss,S.
TI Antibodies Directed Against the Prion protein Receptor LRP/LR Provide Alternative Tools in Prion Diseases
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Pathology and Pathogenesis P03.89
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
The 37kDa/67 kDa laminin receptor (LRP/LR) acts as the cell surface receptor for the cellular prion protein (PrPc) (1) and the infectious prion protein (PrPsc) (2). We proved that the polyclonal antibody W3, was able to abolish PrPsc propagation in scrapie infected neuroblastoma cells (3), demonstrating that the disruption of the LRP-PrP interaction is a relevant strategy in therapies against TSEs (for review (4)). We injected W3 intraperitoneally into scrapie infected mice. Spleen analysis revealed that the PrPsc content was reduced by approximately 66% demonstrating a strong reduction of the peripheral PrPsc propagation. In addition, we observed a prolongation of survival time by approximately 130% compared to the control group suggesting that disruption of the LRP/LR-PrP interaction by antibodies is a promising therapeutic strategy (5).
For antibody delivery into mice we developed single chain antibodies directed against LRP/LR employing a phage display technique. Two scFvs termed N3 and S18 have been selected and characterized (6). A therapeutic effect of the scFvs on scrapie infected mice was investigated by passive immunotransfer resulting in a reduction of the peripheral PrPsc propagation in the spleen of scrapie infected mice by approx. 40% without a significant prolongation of the incubation and survival times.
As an alternative delivery system we developed recombinant AAV encoding for the scFvs (7) and treated scrapie infected mice intracerebrally by a stereotactic device. Although spleen analysis revealed a reduction of the PrPsc level by approx. 50%, the survival times were not significantly prolonged (7). Since scFv S18 did not significantly prolong incubation and survival times in animals we developed an improved version of the single chain antibody, termed iS18, that revealed a ten fold better affinity to the LRP/LR and was able to reduce the PrPsc level in Scrapie infected neuroblastoma cells. iS18 will be delivered to mice by passive immunotransfer and alternative delivery systems such as scFv secreting muscle cells, liposomes packaged with scFvs and lentiviral vectors.
(1) Gauczynski et al. (2001) EMBO J. 20, 5863-5875 (2) Gauczynski et al. (2006) J. Infect. Dis, 194, 702-709. (3) Leucht et al. (2003) EMBO rep 4, 290-295 (4) Zuber et al., Vet. Microbiol, in press (5) Zuber et al., Mol. Therapy, revised (6) Zuber et al., Mol. Immunol. , in press (7) Zuber et al., J Gen Virol, submitted.
AD C. Zuber, C. Rey, M. Hallek, S. Weiss, Gene Center, Institute of Biochemistry, Germany; S. Knackmuss, U. Reusch, M. Little, Affimed Therapeutics AG, Germany; C. Pace, G. Mitteregger, H.A. Kretzschmar, Center for Neuropathology and Prion Research, Germany; T. Fröhlich, G.J. Arnold, Gene Center, Laboratory for Functional Genome Analysis (LAFUGA), Germany; H. Büning, University of Cologne, Internal Medicine, Germany
SP englisch
PO Schottland