Western Blot. Positive WB detected in: A549 whole cell lysate, PC-3 whole cell lysate, HepG2 whole cell lysate, MCF-7 whole cell lysate, 293 whole cell lysate, Hela whole cell lysate. All lanes: PD-L1 antibody at 1:1000. Secondary. Goat polyclonal to Mouse IgG at 1/10000 dilution. Predicted band size: 33 kDa. Observed band size: 55 kDa.