prions and immune response

[Corey Braastad]

In article <20MAY95.10163711.0046 at UNBVM1.CSD.UNB.CA>, JARDINE  P <F3CM at UNB.CA> writes:
>To those still brave enough to wade through the Ebola posts:
>
>I was thinking about prions and the ability of a host to generate an
>immune response. Is there a detectable antibody titre in hosts which
>have been exposed to the prion?
>Technically, if the prion is really a rogue cellular peptide, it
>would not ellicit an immune response since it would be auto-immune.
>However, if the PrP (Sc) has a different conformation from the PrP
>(C) as is speculated, would this provide sufficient epitomes of
>"foreign" appearance for the humoral system to kick in.
>This has very little to do with the nature of disease but I was
>wondering about the immunological consequence. I realize the
>amyloids appear in a priviledged site, but there's so much of it I
>assume that there must be some making its way into the lymph and
>making itself available for the old clonal selection game.
>Not really sure why I thought of this??
>Ciao, PJ Jardine
>


Hello!  I've done some pretty extensive reading lately on prions, 
and it seems to me that few antibodies develop due to the extraordinarily
long incubation time for the diseases, and apparent lack of response by the
immune system.  I may be wrong on this, because I 
have no data to comment on your specific question, however most research
projects utilize synthetic protein fragments derived from the carboxyl end 
(usually 15-28 residues) of the amyloid protein to make an antibody
[Taraboulos, A., et. al., 1992.  Regional mapping of prion
proteins in the brain.  Proc. National Acad. of Science  89, 7602-7624].
I hope that I am not out of step here by attempting to reply, since I am 
certainly not an expert, but maybe this may be of some use...!

Corey Braastad
Molecular Biology-Genetics
UMass at Dartmouth