Western blot res ult of the antibody used at 2 ug/mL to detect platelet derived TGF-β at 12 ug/lane (lane 2) 6 ug/lane (lane 3), 3 ug/lane (lane 4) and 1 ug/mL (lane 5) with 4- chlorol-napthol as substrate. The bottom band is the 12.5KD TGF-β monomer, the mid-band is the 25KD TGF-β dimer and the up band is TGF-β with signal peptide. Lane 1 is molec ular weight markers.