One acknowledged exception is single-donor platelets from selected donors, which are necessary for patients requiring HLA (human leukocyte antigen) compatible and/or HPA (human platelet antigen) compatible platelets, i.e., mainly those with platelet refractoriness due to HLA and/or HPA antibodies as well as in neonatal allo-immune thrombocytopenia (NAIT)). Here, HPSE is linked to fetal and neonatal alloimmune thrombocytopenia.