TrpE-fusion proteins as immunoadsorbents

[David Nunn]

   I am interested in using a TrpE-fusion proteins (from a PATH 
vector) for the affinity purification of antibodies.  The polyclonal 
sera was generated by immunization with the protein of interest 
fused to the maltose-binding protein.  Since high level expression of 
TrpE fusions usually result in the production of insoluble inclusion 
bodies, my question is whether anyone has tried to use these 
insoluble proteins as immunoabsorbents.  The two main questions 
are 1) are these proteins completely insoluble or would there be 
some leaching of protein into the antibody preparation and 2) would 
presumably hydrophilic epitopes be exposed in these inclusions to 
make them effective immunoabsorbents.   If you have any thoughts 
about these questions or any others that you can raise, please 
respond.  I know of many other possibilities for affinity purification 
of antibodies (coupling to activated supports, nitrocellulose blotted 
proteins, glutaraldehyde immobilization inpolyacrylamide gels) but 
thought this might be an interesting method. 
    (E-mail  =   nunn at milton.u.washington.edu)