Although we identified some novel changes in biomarkers not previously associated with ALPS (increased IFNγ, decreased MDC) (21), we did not initially identify any specific change in biomarkers or intrinsic immunophenotypic features of CD4 T-cells that was associated with the reduced number of CD4 T-cells in ALPS-FAS (4, 21, 22). Here, FAS is linked to autoimmune lymphoproliferative syndrome.