Fig. 4
Expression and purification of the S7 antibody. The gene fragment of the S7 antibody was ligated into a modified pET-25b vector and fusion expression with SBP Tag. The recombinant S7 antibody was purified with Ni–NTA agarose and verified with HRP-streptavidin in western blot analysis. Lane M, molecular weight marker. Lane 1, the supernatant of E. coli cell lysate that were transformed with the S7 antibody gene after induction. Lane 2, the flow-through from Ni–NTA Agarose after incubation with the S7 antibody. Lane 3, elution 1. Lane 4, elution 2. Lane WB, western blot analysis of the purified S7 antibody