Detection of u-PA activity and antigen in line no. 19 platelet lysate. (A) Zymogram of 2 separate preparations of lysates from line no. 19 and no. 13 platelets and wild-type platelets in a gel containing (top) or lacking (bottom) 20 μg/mL plasminogen. H indicates human tcu-PA (0.1 ng). From left to right, the platelet lanes had the following amounts of protein added: no. 19, 0.5 μg; no. 19, 0.1 μg; WT, 1 μg; WT, 2 μg, no. 13, 1 μg; and no. 13, 2 μg. (B) Nonreduced Western blot of platelet lysates (10 μg per lane) for line no. 19 and no. 13, wild type, and renal extract (RE) (30 μg per lane) immunoblotted with A10.