During an immune response to acute viral infection, naive CD8+ T cells undergo a rapid activation and proliferation phase, giving rise to effector cells that can serve in a cytotoxic role to mediate immediate host defense, followed by a contraction phase giving rise to self-renewing memory cells that provide long-lasting protection and are maintained by antigen-dependent homeostatic proliferation108–110. The gene discussed is CD8A; the disease is viral infectious disease.