CD8A and allergic disease: CD8+ effector T cell subsets identified thus far include Tc1, Tc2, Tc9, Tc17, follicular cytotoxic T (Tfc), follicular helper T (CD8+ Tfh), and regulatory T (CD8+ Treg), holds significant potential in treating tumors, viral infections, allergies, and autoimmune diseases (135, 136).The majority of effector cells undergo apoptosis with small subset persists and differentiates into memory cells.