As shown previously, the depletion of both NK and CD8+ cells or CD8+ cells alone prior to exposure to HTLV-1WT increased susceptibility to infection (all macaques became infected compared with 75% untreated macaques) and shortened the timeline to seroconversion, with all treated animals seroconverting by week 4 [24,52]. The gene discussed is CD8A; the disease is infection.