Identification of an epitope on the recombinant bovine PrP that is able to elicit a prominent immune response in wild-type mice.
The main cause for the development of transmissible spongiform encephalopathies (TSE) is the conformational change of prion protein from the normal cellular isoform (PrP(C)) into the abnormal isoform, named prion (PrP(Sc)). The two isoforms have the same primary structure, and with PrP being highly conserved among different species, no immune response to PrP(Sc) has been observed in infected humans or other mammals so far. The problem of inducing immune response was encountered when producing monoclonal antibodies against PrP, therefore mice lacking a functional Prnp gene were predominantly used for the immunization. In the present paper we report that by immunizing wild-type BALB/c mice with chemically unmodified recombinant bovine PrP a potent humoral immune response was achieved. Furthermore, we were able to isolate the monoclonal antibody (mAb) E12/2 and few other mAbs, all reacting specifically with bovine and human PrP, but not with PrP from several other mammals. The epitope of mAb E12/2 is located at the C-terminal end of helix 1, with His155 being crucial for binding. It has been proven that mAb E12/2 is useful for human and bovine TSE research as well as for diagnostics. Our results show that there are sufficient structural differences between mouse and bovine PrP to provoke a prominent humoral immune response.
Cernilec
Maja
M
Blood Transfusion Centre of Slovenia, Slajmerjeva 6, 1000 Ljubljana, Slovenia.
Vranac
Tanja
T
Hafner-Bratkovic
Iva
I
Koren
Simon
S
Venturini
Anja Colja
AC
Popović
Mara
M
Juntes
Polona
P
Serbec
Vladka Curin
VC
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D006224:Cricetinae; D003670:Deer; D016643:Encephalopathy, Bovine Spongiform / Q000175:diagnosis / Q000276:immunology; D000939:Epitopes / Q000235:genetics / Q000276:immunology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011328:Prions / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D011817:Rabbits; D051381:Rats; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D012756:Sheep; D013552:Swine
D000939:Epitopes; D011328:Prions; D011994:Recombinant Proteins