CD4 and autoimmune disease: This was initially interpreted as a decrease in suppressor CD8+ T cells leading to disinhibition of autoimmune responses [16, 22, 24, 47, 50] but later attributed to sequestration of CD8+ T cells in the target organ [19, 23, 31] because CD8+ T cells are selectively enriched compared to CD4+ T cells in the target organ in some autoimmune diseases [23, 58].