Western blot. All lanes: GDF15 antibody at 4µg/ml. Lane 1: HepG2 whole cell lysate. Lane 2: Human placenta tissue. Lane 3: A549 whole cell lysate. Secondary. Goat polyclonal to rabbit IgG at 1/10000 dilution. Predicted band size: 35 kDa. Observed band size: 35 kDa