ITGB3 and Glanzmann thrombasthenia: Our cItga2b−/− recapitulated the Glanzmann thrombasthenia phenotype seen in humans and in the previously published Itga2b (αIIb) and Itgb3 (β3) knockout mouse models.25,27 Genotypic analysis confirmed the successful platelet specific knockout of the Itg2b gene, which was validated by flow cytometric and Western blot analyses.