GP1BA and Thrombocytopenia: As previously reported8, acute thrombocytopenia was observed 3 days after anti-CD42b treatment (Fig. 8e), with no impact on other lineages (Extended Data Fig. 10f) or the balance between Flt3Cre-tdTomato+ and Flt3Cre-tdTomato− platelets (Fig. 8f).