In Alloimmune thrombocytopenia antigen against which antibody is found?

Neonatal alloimmune thrombocytopenic purpura (NATP): - Caused by development of maternal antibodies against antigens present on fetal platelets that are shared from father & recognized as foreign by maternal immune system. - The most common cause is incompatibility for the platelet alloantigen HPA-1a.