(A) Family of type 2 N vWD with G22E mutation. Family tree. vWF antigen levels are given below the symbols for the family members. Arrow indicates the propositus (II3). Open symbols (○, □) indicate normal individuals and half-filled symbols (◑,╞ ) indicate the family members who are heterozygous for the mutation. NT, for not tested individuals. (B) Binding of recombinant FVIII to plasma vWF. Serial dilutions of plasma samples were incubated into microtiter plates coated with anti-vWF polyclonal antibodies. A constant amount of recombinant FVIII (0.1 U/mL) was then added and the activity of bound FVIII was determined using a chromogenic assay. The vWF was measured by reaction with a peroxidase-conjugated MoAb as described in Materials and Methods. Plasma samples: (•), pool of normal plasmas; (▪), propositus (II-3); (□), sister (II-7); (▴), mother (I-2); (▿), brother (II-1).