...what do you mean by "framework" antibody? One that specifically
binds the heavy chain in a native-molecular state? I would think it
would be easier to use an antibody to the light chain
(b2-microglobulin), since there is quite a bit of "species-specificity"
with such antibodies. (For example, the MAb to human b2m, BBM.1, will
bind to human and chimpanzee MHC class I but NOT to mouse or even baboon
molecules).
