CD8A and autoimmune thyroid disease: And enriched in the autoimmune thyroid disease pathway, both autoantibodies and thyroid-specific cytotoxic T lymphocytes (CTLs) have been proposed to be responsible for autoimmune thyrocyte depletion (Stassi and De Maria, 2002), and self-reactive CD4+ T lymphocytes (Th) recruit B cells and CD8+ T cells (CTL) into the thyroid (Tsatsoulis, 2006).