Western blot using affinity purified anti-Fbp5B antibody. Panels A and B show two identical membranes containing marker, in vitro translated Fbp5b (Fbp5b ivt), and a whole cell extract from 293T cells loaded in duplicate). Panel A shows antibody reactivity. Panel B shows antibody reactivity after first pre-incubating the antibody with the immunizing peptide. This pre-incubation greatly diminishes specific band recognition. Peptide inhibition completely removes the in vitro translated band and greatly reduces the endogenous band from 293T cells. When this experiment was repeated using a mock in vitro translation, no band was detected (data not shown). Personal Communication, Daniele Guardavaccaro, NYU Cancer Institute