To investigate whether PD-1 is implicated in other AA animal models, 2-month-old male PD-1–KO and WT C57BL/6J mice (34) were fed a HFD for 1 month and then infused with Ang II in the continued presence of HFD feeding for an additional month to induce AAA (35). Here, PDCD1 is linked to triple-A syndrome.