Platelet migration inhibition: a new method for detection of platelet antibodies.

A test for platelet antibodies based on the inhibition of migration of platelets from a capillary tube is described. The technique is simple and is capable of detecting antibodies directed against HL-A antigens and the platelet-specific antigen, Pl-A1. Inhibitory activity was detected in sera from two of seven patients with idiopathic thrombocytopenic purpura. The platelet migration inhibition test was as sensitive as platelet lysis and more sensitive than complement fixation, aggregometry, and platelet factor-3 release for detection of the antibodies studied.