In article <94321.134938FORSDYKE at qucdn.queensu.ca>,
<FORSDYKE at QUCDN.QueensU.CA> wrote:
>In article <3adfp6$g8k at news.uni-c.dk>, kesmir at mimer.be.dtu.dk (Can Kesmir) says:
>>>>Therefore I would like to start a debate about the existence of
>>immune networks. Please write your meaning about them with a
>>little bit of reasoning.
>>
[snip]
> Generation of diversity (GOD) in Immunologically Competetent Cells results
>in cells of unique specificity. If this specificity is not eliminated during
>the process of "education" (thymic, or elsewhere), then that specificity
>becomes part of "self". The education of future ICCs should then be with
>respect to a self-image which includes the specificities of previously
>generated ICCs. For this reason, I am not convinced by immune network ideas.
>Only ICCs of very low specificity against previous ICCs would be tolerated by
>the education process. Thus, it might be possible for networks to arise, but
>the specificities would be so low as, perhaps, not to be very important.
>Autoantibodies arise because sometimes the learning process goes wrong. The
>existance of autoantibodies does not prove that networks are an important
>feature of normal immune responses.
> Sincerely, Don Forsdyke
> Discussion Leader. Bionet.immunol.
This argument assumes that the specific epitopes found on the ICC's are at
frequencies high enough to be detected. If a given epitope is found only on
a single cell, it is unlikely that it will be able to "educate" future ICC's.
However, during the expansion involved in an immune response, it is possible
to generate reactions against these epitopes (especially secreted antibodies).
Although the constant regions of these receptors (and probably some V and J
regions as well) would be common enough to "educate" future ICC's, I find it
difficult to believe that receptor idiotopes would elicit *any* kind of
detection until an immune response. Also, the presence of anti-idiotype
antibodies in immune responses suggests that there is at best limited
tolerance toward the "specificity" components of ICC's.
BioKen
--
Ken Frauwirth (MiSTie #33025) _ _
frauwirt at mendel.berkeley.edu |_) * |/ (_ |\ |
Dept. of Molec. & Cell Bio. |_) | () |\ (_ | \|
Univ. of Cal., Berkeley Push the button...someone :(
