CHARACTERIZATION OF HUMAN-PLATELET GLYCOPROTEIN ANTIGENS GIVING RISE TO INDIVIDUAL IMMUNOPRECIPITATES IN CROSSED-IMMUNOELECTROPHORESIS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 58  (6) , 1190-1197
Abstract
Washed human platelets were labeled with 125I by the lactoperoxidase-catalyzed method and solubilized in 1% Triton X-100. The soluble proteins were analyzed by crossed immunoelectrophoresis in 1% agarose, using a rabbit antibody raised against whole human platelets. Analysis of autoradiograms developed from dried agarose gels led to the establishment of a normal reference pattern that was consistent for platelets obtained from > 50 normal individuals. Six platelet membrane glycoprotein antigens contained in 4 distinguishable precipitates were identified. Each identification was based on direct sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of 125I-antigens contained in individually excised precipitates. These platelet antigens include major membrane glycoproteins previously designated Ia, Ib, IIa, IIb, IIIa and IIIb. Glycoproteins IIb and IIIa were contained in a single immunoprecipitate, while glycoproteins Ia and IIa were routinely detected in a single different immunoprecipitate. Analysis of soluble proteins from platelets of 5 patients with Glanzmann''s thrombasthenia demonstrated either a complete absence or a marked reduction of only 1 radiolabeled precipitate, that containing membrane glycoproteins IIb and IIIa. Platelet samples from 2 patients with Bernard-Soulier syndrome were devoid of a different precipitate, that containing membrane glycoprotein Ib.