PTPRC and autoimmune lymphoproliferative syndrome: As previously described, a large proportion of the expanded population of TCRαβ+ DNT-cells present in ALPS-FAS patients also expressed the B-cell-specific CD45R isoform B220 [median 10% (IQR: 2–19) n = 3 in HC vs. 57% (IQR: 43–72), n = 21 in patient with ALPS-FAS, p < 0.0001].