To avoid active autoimmune diseases confounding our analyses, 6-week-old Rig-I+/+ or Rig-I–/– mice were used, as under the age of 8–10 weeks, C57 background Rig-I–/– mice looked as healthy as Rig-I+/+ littermates, with similar spleen sizes and apoptotic/activated level of splenic CD8+ T cells (Supplemental Figure 1, A–E; supplemental material available online with this article; https://doi.org/10.1172/JCI160790DS1). Here, CD8A is linked to autoimmune disease.