Fig. 1.
Recombinant calreticulin expression, characterization, purification, and antibody generation. (A) Lysate of Sf9 cells infected with recombinant baculovirus was chromatographed on DEAE-Sepharose and aliquots of the fractions were analyzed by 7.5% SDS-PAGE and Coomassie Blue staining. Recombinant calreticulin is seen as a prominent 60-kD band in the Sf9 cell lysate (lane marked L) and in column fractions 11 and 12. The lane marked S shows standards with molecular weights as indicated. (B) The same Sf9 cell lysate as in (A) was analyzed by 7.5% SDS-PAGE and staining with Stains-All. The prominent 60-kD band stained blue, whereas other bands stained faintly red and are not visible in the photograph. (C) Purified recombinant calreticulin was analyzed by 7.5% SDS-PAGE, transfer to nitrocellulose, and detection by immunoblotting using a 1:1,000 dilution of rabbit polyclonal antibody to the purified protein. (D) Purified recombinant calreticulin was analyzed by 7.5% SDS-PAGE and silver staining. The left lane is the purified protein and the right lane shows standards with molecular weights as indicated.