Immunoprecipitation analysis of the GPIb-Ibβ-IX complex of Iy^a-phenotyped platelets.

Platelets from Iy^a-positive (lane 1) and Iy^a-negative (lane 2) individuals were surface labeled with biotin, lysed, and immunoprecipitated with anti-Iy^a (left panel) and monoclonal antibody (MAB) Gi27 (right panel). Immunoprecipitates were analyzed with 7.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions, transferred to nitrocellulose membrane, and visualized by using a streptavidin-horseradish peroxidase–chemiluminescence substrate system.