(A) Immunogenicity of recombinant SET proteins with human patient sera. SDS-PAGE gel of lysates of E. coli expressing recombinant SET protein variants. Lanes 1 to 11, SET1 to SET11, respectively; lane 12, lysate of E. coli containing the expression vector only. Note that SET8 and SET9 resolve at approximately twice their expected molecular weight, thus indicating a dimeric form of the protein (see Western blot analysis in panel B). (B) Representative Western blot analysis of recombinant SET proteins with convalescent-phase serum from human patient 2. Lanes 1 to 11, SET1 to SET11, respectively.