FIG. 3.

Oligomer formation of rIb on Vero cells. (A) Vero cells were incubated with ¹²⁵I-labeled Ib at 4°C for 120 min, washed, and incubated at 37°C for the time (in minutes) indicated. The cells were dissolved in SDS-sample buffer and subjected to SDS-7.5% PAGE without heating followed by autoradiography. (B) Vero cells were incubated with ¹²⁵I-labeled Ib at 4°C for 120 min, washed, and incubated in the presence (○) or the absence (•) of a 50-mol excess of cold rIb at 37°C for the time indicated. The radioactivity of labeled Ib oligomer (a 500-kDa band) was determined using a Fuji BAS 2000 system.