Plasma VWF multimer profiles. (A) Patient's VWF multimer profile. Autoradiograph of plasma VWF multimers for normal plasma (lane 1), propositus' plasma (lane 2), and a type 2A VWD control plasma (lane 3). Plasma samples were electrophoresed through a 1.6% SDS-agarose gel and multimers were visualized by chemiluminescence. The highest molecular weight multimers and all the satellite bands are absent from the propositus' plasma. (B) Densitometry of VWF multimers for normal plasma (top lane), propositus' plasma (middle lane), and a type 2A VWD control plasma (bottom lane). Densitometry was performed on the same 1.6% SDS-agarose gel as in panel A. The values shown are for the area under the curve in square pixels. For the normal, the total number of pixels is 19 945, with 4284 pixels or 21% above the ninth multimer band. For the propositus, the total is 9509, with 1129 (11%) above the ninth multimer band. For the type 2A VWD control, the total is 13 740, with 737 (5%) above the ninth multimer band. LMW indicates low molecular weight; HMW, high molecular weight.