[Immunoenzyme method of determination of Willebrand's platelet factor]

A method for Willebrandt factor antigen measurement in platelets has been developed based on indirect solid-phase enzyme immunoassay with monoclonal antibodies. The mean platelets Willebrandt factor level in 17 normal subjects was 21.5% (S = +/- 8.88; S mean = 2.16%). The method was tried in a group of patients with Willebrandt's disease. A relationship was demonstrated between Willebrandt platelet factor level and the degree of disorders in hemorrhage duration.