In article <3F2069C9.8010803 at NOSPAM.ucalgary.ca>,
Bryan Heit <bjheit at NOSPAM.ucalgary.ca> wrote:
>>>But in this case it is more likely the multi-reacting antibodies are
>identifying shared epitopes between the different sub-classes. For
You're making a circular argument, or else turning this into a completely
unfalsifiable (i.e. non-scientific) question. An antibody sees an
epitope. Therefore whatever it binds to, has that antibody's epitope.
Therefore even if it binds to two completely different proteins they must
(by this definition) have the same epitope. Therefore, an antibody can by
definition only bind to two proteins if they have the same epitope.
But that's a completely useless argument. It's true merely by definition,
because you are presenting as an axiom the thing you're trying to
prove--that an antibody cannot bind to completely unrelated proteins. By
any reasonable argument, if an antibody binds to two completely unrelated
proteins, then it's binding to two completely unrelated proteins--even if
they fortuitously happen to have a similar structure on a
solvent-accessible surface.
Ian
--
Ian York (iayork at panix.com) <http://www.panix.com/~iayork/>
"-but as he was a York, I am rather inclined to suppose him a
very respectable Man." -Jane Austen, The History of England
