Figure 4

Comparison of the new and conventional immunoblot (IB) methods for probing complement C5 in human serum. Arrows indicate human complement C5 (190 kDa). (a) Immunoblot was probed with the bispecific tandem single-chain variable fragment (scFv)-Fc fusion protein recognizing both C5 and cotinine and then with cotinine–horseradish peroxidase (HRP) (left) or HRP-conjugated goat anti-rabbit IgG (Fc-specific) antibody (right). (b) The same set of blots was incubated only with cotinine–HRP (left) or HRP-conjugated goat anti-rabbit IgG (Fc-specific) antibody (right).